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Moon and Gemini stars on May 1

Tonight – May 1, 2017 – the waxing crescent moon shines near the stars Castor and Pollux in the constellation Gemini the Twins. Watch for them in your western sky as darkness falls. Another bright star, Procyon, shines on the other side of the moon.

Also, look eastward at dusk and nightfall to see the planet Jupiter, the brightest starlike object in the evening sky. The star in Jupiter’s vicinity is Spica, the brightest star in the constellation Virgo the Maiden.

As evening deepens into late night, watch for the planet Jupiter, the star Spica and the constellation Corvus to climb higher up in the sky. Later this evening, the threesome will be found in the Northern Hemisphere’s southern sky. From the Southern Hemisphere, look for the heaven trio to soar overhead, or high in your northern sky. From temperate latitudes in the Southern Hemisphere, you’ll actually see an “upside-down” Corvus above Jupiter and Spica.

The unlit portion of a waxing moon always points in its direction of travel – eastward – in front of the backdrop stars. As Earth spins beneath the sky, though, the moon, stars and planets go westward throughout the night. But over a period of days, you can notice that the moon is actually traveling eastward relative to the constellations of the zodiac.

That eastward motion of the moon is a reflection of the moon’s true motion in orbit around Earth. As a result of the moon’s eastward (orbital) motion, the moon will move somewhat closer to the star Regulus and the planet Jupiter by this same time tomorrow evening (May 2). It’ll finally partner up up with the star Regulus on the nights of May 3 and 4 and the planet Jupiter on the night of May 7.

Looking ahead, the waxing moon passes in front of the constellation Leo the Lion on May 3, 4 and 5.

As seen from the Southern Hemisphere, the moon passes between the Gemini stars and Procyon once a month, just as in the Northern Hemisphere. However, people living south of the equator will see Procyon higher in the sky and the Gemini stars lower down.

Up or down is a matter of perspective, in the sky as in so much else.

To avoid ambiguity, in talking about the sky, we can say that Castor and Pollux lie north of the moon (in the direction toward the North Star), and Procyon lies south of the moon (in the direction away from the North Star).

Meanwhile, Jupiter lies east of the moon (toward the sunrise direction) as darkness falls over the next few days.

Bottom line: Tonight – May 1, 2017 – you’ll find the moon, the Gemini stars, the star Procyon in the western part of the sky.

EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store

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from EarthSky http://ift.tt/2qmtSsa

Tonight – May 1, 2017 – the waxing crescent moon shines near the stars Castor and Pollux in the constellation Gemini the Twins. Watch for them in your western sky as darkness falls. Another bright star, Procyon, shines on the other side of the moon.

Also, look eastward at dusk and nightfall to see the planet Jupiter, the brightest starlike object in the evening sky. The star in Jupiter’s vicinity is Spica, the brightest star in the constellation Virgo the Maiden.

As evening deepens into late night, watch for the planet Jupiter, the star Spica and the constellation Corvus to climb higher up in the sky. Later this evening, the threesome will be found in the Northern Hemisphere’s southern sky. From the Southern Hemisphere, look for the heaven trio to soar overhead, or high in your northern sky. From temperate latitudes in the Southern Hemisphere, you’ll actually see an “upside-down” Corvus above Jupiter and Spica.

The unlit portion of a waxing moon always points in its direction of travel – eastward – in front of the backdrop stars. As Earth spins beneath the sky, though, the moon, stars and planets go westward throughout the night. But over a period of days, you can notice that the moon is actually traveling eastward relative to the constellations of the zodiac.

That eastward motion of the moon is a reflection of the moon’s true motion in orbit around Earth. As a result of the moon’s eastward (orbital) motion, the moon will move somewhat closer to the star Regulus and the planet Jupiter by this same time tomorrow evening (May 2). It’ll finally partner up up with the star Regulus on the nights of May 3 and 4 and the planet Jupiter on the night of May 7.

Looking ahead, the waxing moon passes in front of the constellation Leo the Lion on May 3, 4 and 5.

As seen from the Southern Hemisphere, the moon passes between the Gemini stars and Procyon once a month, just as in the Northern Hemisphere. However, people living south of the equator will see Procyon higher in the sky and the Gemini stars lower down.

Up or down is a matter of perspective, in the sky as in so much else.

To avoid ambiguity, in talking about the sky, we can say that Castor and Pollux lie north of the moon (in the direction toward the North Star), and Procyon lies south of the moon (in the direction away from the North Star).

Meanwhile, Jupiter lies east of the moon (toward the sunrise direction) as darkness falls over the next few days.

Bottom line: Tonight – May 1, 2017 – you’ll find the moon, the Gemini stars, the star Procyon in the western part of the sky.

EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store

Donate: Your support means the world to us



from EarthSky http://ift.tt/2qmtSsa

Thanks for the measles yet again, Andy [Respectful Insolence]

There are many harms attributable to the antivaccine movement and its promotion of antivaccine beliefs. Certainly, the harm those of us who have been combatting antivaccine misinformation fear is the return of vaccine-preventable diseases, which is something we’ve seen in the form of outbreaks, such as the Disneyland measles outbreak two years ago and, in my own state, pertussis outbreaks. The Disneyland outbreak was a wake-up call to California legislators, who in its wake passed SB 277, a law that eliminated personal belief exemptions (PBEs) to school vaccine requirements. Now, only medical exemptions are permitted, and so far the law has worked well. In Michigan, we’re still struggling. The Michigan Department of Health and Human Services issued a new rule that requires parents seeking a PBE to attend an education and counseling session at a local county health office before the PBE is issued. Not surprisingly, local antivaxers are not happy and have managed, by painting this rule as a horrific affront to “freedom” and “parental rights,” to persuade legislators to try to pass a law that would not only revoke the rule and explicitly bar MDHHS from issuing similar rules in the future, but it would prevent local health officers from barring unvaccinated children from school during an outbreak. The law failed to pass the first time it was introduced, but Michigan legislators are nothing if not extremely persistent in pursuing harmful policies, and a new version of the same old bill is again under consideration. It matters not one whit to our stupid legislators that the rule change is starting to work to increase vaccine uptake. Unfortunately, we have a fair number of antivaccine and antivaccine-sympathetic legislators.

Although the antivaccine movement in the US has classically been associated with upper middle class and affluent white people, they are not the ones who are likely to suffer the most when herd immunity breaks down. I’ve written extensively here about how the newest (and perhaps most pernicious) antivaccine conspiracy theory, the so-called “CDC whistleblower” conspiracy theory promoted by Del Bigtree and Andrew Wakefield’s propaganda film disguised as a documentary VAXXED, explicitly targets the African-American community, complete with promotional visits featuring the Nation of Islam going to speak in Compton and being involved in protests outside the CDC. Wakefield, as you recall, is the British gastroenterologist who in 1998 published a case series in The Lancet linking MMR to autism. It has since been retracted and shown to have been fraudulent, and Wakefield has had his UK medical license stripped from him. Unfortunately, that only makes him more of a hero to the antivaccine movement, and he’s spent the last 19 years playing that role to the hilt.

The “CDC whistleblower” conspiracy theory is based on the story of CDC scientist William Thompson, who in 2013 apparently contacted biochemical engineer turned incompetent antivaccine epidemiologist Brian Thompson to vent about a study he co-authored in 2004 that examined whether there was a correlation between vaccination with MMR and subsequent risk of autism. Not surprisingly, the study failed to find a correlation. However, there was one subgroup, African-American boys, in which the unadjusted data showed a 3.4-fold increased risk of autism. (I’m simplifying for space considerations in providing background, obviously; if you want the gory details, read here and here for a contemporaneous account of the origin of a new conspiracy theory, as well as my review of the book Vaccine Whistleblower and Andrew Wakefield’s fraudumentary VAXXED.) Thompson had had disagreements with how the data were presented and how he thought the CDC has “suppressed” the unadjusted data. Unfortunately for him, Thompson didn’t realize that Hooker was recording their conversations, and Andrew Wakefield found out about it. Thus, he became the “CDC whistleblower” who seemingly validated what I like to call the central conspiracy theory of the antivaccine movement, specifically that the CDC “knows” that vaccines cause autism but covered it up. It didn’t matter one whit that the correlation was found only in a small subgroup (African-American boys), but it did matter because African-Americans already have reason to distrust the medical community based on history. The “CDC whistleblower” myth feeds into that sad history, which is why Wakefield loves to invoke the Tuskegee syphilis experiment.

This is also not the first time Andrew Wakefield has targeted people of color with his pseudoscience. By any objective measure, for the most part the CDC whistleblower conspiracy theory and VAXXED have not had much resonance in the African-American community other than in the Nation of Islam and among a handful of parents like Sheila Ealey who really believe vaccines caused their children’s autism. The first time around, unfortunately, Wakefield was much more successful. Now, nearly a decade after he first started targeting the community, they are continuing to suffer measles outbreaks. I will begin with the story as it stands now and then go back and look at how it got to this point. The story takes place among a seemingly unlikely group of people in an unexpected location. It’s also a story that I can’t believe I’ve never blogged about before, given how long it’s been going on.

Measles outbreaks among Somali immigrants in Minnesota

Before I first encountered this story several years ago, I had no idea that there was a large community of Somali immigrants in Hennepin County in Minnesota, but there is. In fact, it’s the largest community of Somali immigrants in the US that began forming over a quarter of a century ago and now numbers in the several tens of thousands. Right now, the community is the center of a new measles outbreak, which is just the latest. From the StarTribune a week ago:

As a registered nurse and a consultant to the Minnesota Department of Health, Asli Ashkir has spent nearly a decade talking with Somali parents about autism, vaccines and the importance of getting their children immunized.

Last week she redoubled her efforts. A measles outbreak in Hennepin County has sickened 12 children — all of them unvaccinated and all of them from Somali families, according to the department — throwing a spotlight on low immunization rates among Somali children.

Now state and county public health workers are doing their best to contact Somali parents and underscore the value of immunization. “I know when parents have facts, they do the best they can to make the right decision,” Ashkir said.

I note that the total number of children sickened had reached 32 by the weekend, and the toll is still growing.

The story shows why the Somali community in the Twin Cities area is so susceptible to measles outbreak. All you have to do is to look at this graph of MMR vaccine uptake by year:

MMR uptake among Somali immigrants in Minnesota: This is the effect of nearly a decade of antivaccine propaganda.

MMR uptake among Somali immigrants in Minnesota: This is the effect of nearly a decade of antivaccine propaganda.

The graph above shows what can only be described as a catastrophic plunge over the course of just one decade in MMR uptake among American-born children of Somali descent, from 92% to 42%. There is, for all intents and purposes, no herd immunity in this community. The interesting thing here, though, is that this plunge is very specific. It’s noted in the story that there is not a fear of vaccination in general among the Somali immigrant population. Rather, it’s fear of just one shot: the MMR. It is a fear that antivaxers stoked, beginning sometime around 2008, and they have unfortunately been wildly successful in inculcating fear of the MMR in Somalis in Minnesota. Indeed, a 2014 study examined attitudes towards the MMR vaccine in Somali and non-Somali children in Minnesota and found:

Somali parents were more likely than non-Somali parents to have refused the MMR vaccine for their child (odds ratio, 4.6; 95% confidence interval, 1.2–18.0). Most of them refused vaccines because they had heard of adverse effects associated with the vaccine or personally knew someone who suffered an adverse effect. Somali parents were significantly more likely to believe that autism is caused by vaccines (35% vs. 8% of non-Somali parents). Somalis were also more likely to be uncomfortable with administering multiple vaccines at one visit (odds ratio, 4.0; 95% confidence interval, 1.4–11.9) and more likely to believe that children receive too many vaccines.

It was a small survey, but it was the only one I found in the peer-reviewed medical literature thus far. Its results are not surprising, however, to anyone directly involved with the Somali community, particularly public health officials. There haven’t (yet) been studies published about this latest measles outbreak, but there was a study about the 2011 measles outbreak in Minnesota, which, to that point, was the largest such outbreak in 20 years, with 21 cases identified. Its conclusions were also unsurprising. The source was found to be a 30-month-old US-born child of Somali descent infected while visiting Kenya and then spread to the Somali and non-Somali population primarily through the unvaccinated:

Three case-patients had unknown vaccination status, 1 was vaccinated before the recommended age (11 months), and 1 was a health care worker who was thought to be immune (IgG-positive documented >10 years previously). Sixteen of 21 (76%) were unvaccinated; 7 of 16 (44%) were too young for routine vaccination. Nine (56%) children were age-eligible for routine vaccination but unvaccinated, 7 because of safety concerns owing to the misinformation that MMR vaccine causes autism; 6 of these children were of Somali descent. Two other children did not refuse but were behind on immunizations.

This is how the outbreak spread:

This outbreak began with an unvaccinated US-born child who was exposed to measles in an endemic region of Africa and developed disease on return to the United States. Low vaccination rates in the local Somali community, and subsequent exposures among susceptible homeless shelter residents, fueled ongoing transmission of measles. Delay of the source case-patient’s measles diagnosis also may have contributed to transmission before public health interventions. Although post-exposure prophylaxis, vaccination, and voluntary isolation and quarantine were implemented after the first known case, there was ongoing transmission in 1 of the 2 affected shelters. This transmission was attributable to several factors, including exposures that occurred before the first identified case, an exposure of an infant too young for MMR vaccine according to the routine schedule, as well as exposure of an infant who was too young for the early MMR vaccine outbreak recommendation. Other contributing factors were caused by the challenges of quickly assessing and documenting immune status in a large group of individuals living in a temporary, communal setting. These challenges allowed transmission to individuals who initially were assumed to be immune, but who lacked documentation. After ongoing transmission was seen, immune status testing was implemented for those who lacked documentation.

Notably, two-thirds of the cases in this outbreak were hospitalized, and many of these were hospitalized for respiratory complications in addition to dehydration, highlighting that measles is a severe infection even in well-resourced countries.

If measles is as harmless as antivaxers claim that it is, then why were two-thirds of the people stricken with measles in this outbreak hospitalized for complications? That’s a rhetorical question for antivaxers, obviously.

The first question that faces Minnesota public health officials is, of course: How did we get here? The second is: What can be done to combat MMR fear-mongering? I can’t help but note that the fear of the MMR that is so prevalent among Somali immigrants in Minnesota, while primarily about the MMR, is bleeding over to other vaccines. Some Somali immigrants are starting to show susceptibility to the “too many too soon” myth and, as a result, spacing out the remaining vaccines other than the MMR that they are willing to administer to their children, believing that early vaccination can “damage an infant’s language skills.” Basically, if you live in Minnesota, combatting antivaccine and anti-MMR views in the Somali immigrant community is imperative. Even if you don’t live there, given that the Twin Cities area is a hub of national and international transportation, measles could be as short as a quick plane flight to where you live.

So let’s look at how we got here. Andrew Wakefield has his fingerprints all over this, but it didn’t start with him. As is his usual MO, he opportunistically took advantage of a situation, as he did when he discovered that Brian Hooker had been recording telephone conversations with a disgruntled CDC scientist.

2008: Autism in the Somali immigrant community

The story of how the myth that MMR causes autism became so firmly entrenched among Somalis living in Minnesota began sometime around 2008, with a cluster of autism cases among the community and a news story, as described by Bahta et al. in Minnesota Medicine:

Parents in Minnesota’s Somali community have voiced concern that their children are disproportionately affected by autism spectrum disorder (ASD) compared with children of other ethnicities. Many in the community blame the MMR vaccine. In an August 2008 news story on WCCO-TV, one parent was quoted as saying, “It’s the vaccines.”

Shortly after the story aired, the Minnesota Department of Health reached out to members of the Somali community to gather more information. Health department staff attended meetings with Somali parents, many of whom were unfamiliar with ASD. Repeatedly, they stated that they don’t even have a word for autism in their language. In telling her story, one mother reported that in their attempt to understand ASD, she and others discovered groups that supported the claim that vaccines, particularly MMR, cause autism. Misinformation can spread rapidly in the Somali community, which has a rich oral tradition of passing information to one another. It is now widely accepted among Somali Minnesotans that MMR is to blame for autism.

The antivaccine movement was all over this story in 2008. For example, David Kirby, author of the book Evidence of Harm: Mercury in Vaccines and the Autism Epidemic: A Medical Controversy, which was one of the early works using pseudoscience to link thimerosal in vaccines to autism was writing articles like ‘Autism May Be Caused By “Chemical Exposures”‘ specifically about the Somali community in Minnesota, with a “wink, wink, nudge, nudge” that the “idea that ‘chemical exposures’ (vaccine related or otherwise) might cause autism still brings virtual apoplexia to certain scientific circles.” He had previously hammered the same theme on the antivaccine blog Age of Autism, noting from the data presented that “rate of autism among Somali children in the public schools had been reported at 1 in 28 kids” and that the “80 or so Somali parents who attended were disappointed, by all accounts, that Dr. Punyko had no way to tell them if autism among their children was, as they strongly suspect, more common than among non-Somalis the same age.”

But was autism more than twice as common among the American-born children of Somali immigrants, as the data linked to above suggest? In early 2009, the Minnesota Department of Health released a study of autism among Somali immigrants. It is a substantial read. Here are a couple of key findings, which, as is often the case in studies of autism compared to parental perception of autism prevalence, are not as clear as the prevalent belief among the Somali community in Minnesota or as the antivaccine movement latched onto:

  • The administrative prevalence for three and four year old Somali children was significantly higher than for non-Somali children. This is consistent with the perceptions of the community that a larger number of Somali children were participating in ASD programs. Because of the study’s limitations, it is not proof that more Somali children have autism than other children; however, it does raise an important question about why Somali children are participating in this program more than other children.
  • The relative difference between Somali and non-Somali administrative prevalence decreased markedly over the three years covered by the study. It is unclear if this is an identification issue, a change in parental awareness for the need for developmental screening or some other issue.
  • Administrative prevalence rates for the Asian and Native American groups were found to be “strikingly low.” The reasons for these low rates are unknown, but they could be important to understanding whether the rate of ASD is higher among Somali children or underestimated among other children. In other words, the seemingly low prevalence rate among Asian and Native American children may artificially boost the comparative rate among Somali children, distorting a true understanding of all groups involved.

So, yes, administrative prevalence of autism was higher among Somali-Americans in Minnesota, but there were a lot of issues that made it difficult to use these data to determine for sure whether actual autism prevalence was higher, not the least of which was that as was noted in Left Brain, Right Brain, Department of Education data are not reliable for tracking autism. Jim Laidler made the same point in a publication in Pediatrics in 2005. Indeed, the most recent study of autism in the Somali-American community in Minneapolis was published in 2016 and found that Somali children were as likely to be identified with an autism spectrum disorder (ASD) as white children but that Somali children with ASD were significantly more likely to have an intellectual disability than children with ASD in all other racial and ethnic groups. Meanwhile, Steve Novella examined the cluster and proposed other potential causes for it, if even there was a cluster, such as vitamin D deficiency or a founder effect. Of course, as I pointed out above, it appears that children born to Somali immigrants are no more likely to be diagnosed with autism than white children; so there wasn’t even a cluster there. Unfortunately, it took eight years to figure that out.

By long before then, the damage had been done and the seed of distrust in the MMR and other vaccines had been planted by antivaxers. Over the next several years, as you will see, antivaxers nurtured that seed until it blossomed in the form of measles outbreaks.

Enter Andrew Wakefield

It’s not clear exactly when Andrew Wakefield first made contact with the Minnesota Somali community, but I do know that Age of Autism was on the case as early as August 2008 and that the founder of the antivaccine group Generation Rescue J.B. Handley published “An Open Letter to the Somali Parents of Minnesota” in which he told them it was the vaccines and that they can’t trust the local health authorities. He even went so far as to urge them to declare a “state of emergency within your community and create a new vaccine schedule for your kids.” Meanwhile, also as early as August 2008, David Kirby had been writing stories like ‘Is Autism an “American Disease?” Somali Immigrants Reportedly Have High Rates.’

I do know for sure from media accounts and triumphant blog posts in Age of Autism that he met multiple times with the community and its leaders between 2010 and 2011 and that he appears to be still intermittently in contact. For instance, here is one contemporaneous account in local media from 2010. It was a time when he proposed as “study” of autism in Somali immigrants and promised to raise funds for it, something he appears never to have done. At the same time he sold the study this way:

Minnesota Somalis worried about autism rates among their children recently invited controversial British researcher Andrew Wakefield to Minneapolis to talk to their community.

At a Somali community meeting in Minneapolis, Wakefield asked his audience to participate in a study. He told about a hundred people gathered at a Somali-owned restaurant that they could help find the cause of autism.

“It is solvable, it has a cause, it had a beginning and it must have an end,” Wakefield said. “We cannot accept the damage that is being done to all of these children. It is completely unacceptable and the suffering you’re going through.”

At the same talk, Wakefield claimed that there were no known cases of autism in Somalia, characterized in the story as an “anecdotal observation many Somalis confirm.” It staggers the mind that Wakefield would make such a claim (OK, actually, it doesn’t, given how big a liar Wakefield is), but it does not stagger the mind that Minnesota Somalis would find such a claim credible. Somalia is a poor country, and it does not stretch the imagination to speculate that most people living there are unfamiliar with autism. Nor does it bend credibility too much to observe that a Third World country is unlikely to have the same sort of screening and support programs for autism that we have in the US and other developed countries and that in such countries most cases of autism other than the most severe would go undiagnosed. Indeed, even the severe cases might well be diagnosed as mental retardation rather than autism.

Be that as it may, the cluster of autism in 2008 led to perceptions like this one:

She recalled a Somali mother who spoke at a public health meeting at the Brian Coyle Community Center some years ago. She had given birth to several healthy children in Africa, but her first child in the United States showed autism symptoms at an early age.

Wakefield visited Minneapolis again right in the middle of the 2011 measles outbreak to give a talk at a Somali restaurant. It was noted at the time that there were “a number of vocal pediatricians and doctors of Somali descent trying to speak out about this” but that distrust of health authorities was very high and local antivaccine groups like the Vaccine Safety Council of Minnesota were actively influencing Somalis. They still are. In 2016, for instance, the VSCM board member Patti Carroll published a warning to Somali parents that the Minnesota Department of Health “schools professionals to persuade Somali parents to give their children the MMR vaccine, despite clear opposition.”

Gee, you say that as though it were a bad thing.

That’s the problem, of course. Antivaxers are opportunistic in the extreme. If they see a population who are vulnerable to their disease-promoting message, they will pounce, and it’s always about the vaccines. They saw a story of a possible autism cluster among the children of Somali immigrants in Minnesota. Where scientists see such a story and ask “Is the cluster real and not spurious?” and “If it’s real, what might be causing it?” antivaxers see such a story and assume it absolutely, positively must be the vaccines. In this particular case, they took advantage of a newly arrived immigrant community’s lack of knowledge about autism and vaccines, its tradition in which information is primarily transmitted orally, and the distrust some of its members had for the local health authorities. The results are still playing out in catastrophically low MMR uptake and measles outbreaks.

Over the weekend, it got even worse, as a coalition of antivaccine groups gathered together to tell the Somali immigrant population that the “the epidemic is autism, not measles”:

As Minnesota confronts its second measles outbreak in seven years, public health officials are battling to contain the disease while also trying to educate parents in the face of an organized opposition.

As happened in 2011, anti-vaccine activists are reaching out to Minnesota’s Somali community, where both outbreaks have been centered, with messages that reinforce the discredited belief that vaccines cause autism.

On Sunday afternoon, a coalition of anti-vaccine organizations plans a meeting at the Brian Coyle Community Center on Minneapolis’ West Bank in an effort to bring their message to Somali families, saying “The epidemic is autism, not measles.”

Just what the Minnesota Somali immigrant community needs.

What can be done?

As every source I’ve read over the years about the Minnesota Somali community and vaccines has stated, suspicion and fear of the MMR vaccine are now very much entrenched and will be very difficult to reverse. Indeed, it’s been pointed out:

Minnesota Department of Health staff found that fear of autism was often the reason for parents’ refusal to have their children vaccinated. Highly educated Somali Minnesotans are not exempt from this fear. As one Somali educator admitted, “My children did not get the MMR; my evidence is the Somali children I see who have autism.”

Parents who cited fear of autism as the reason for their vaccine hesitancy told health department staff that they received their information mostly from other Somali Minnesotans. Being told that MMR does not cause autism was not satisfactory for many parents because no one could tell them what does cause autism. Yet, when asked whom they would trust for health information, nearly all said they trusted their health care provider. And a significant number who refused vaccinations said they would reconsider their decision if they were given more information.

Parents of children diagnosed with ASD were articulate about their belief in an association between MMR and autism and sometimes also implicated receipt of multiple vaccines as the cause of their child’s autism. Some Somali parents have come to realize that autism and vaccines are unrelated, but they are in the minority.

Vaccine hesitant Somali parents thus resemble our own native-grown antivaxers and vaccine hesitant parents in many ways. Many are highly intelligent and educated. They get their misinformation about vaccines and autism from their peers more than from medical authorities. Also, it is the parents who have children diagnosed with ASD who are the most passionate and persuasive in arguing that vaccines are linked with autism, and, because of the low rate of measles (thanks to the MMR) many Somali parents view autism as a greater threat to their children than the measles and base their decisions about vaccines on that misperception. One difference is that, unlike many of our native antivaxers, Somali immigrants generally hold the medical profession in high esteem and are thus more open to being influenced by physicians and other clinicians. Actually, I should be a bit more clear. American antivaxers generally distrust the medical profession, while American parents who are vaccine-hesitant tend to hold the medical profession in higher esteem.

Be that as it may the Minnesota Department of Health has been trying to meet the challenge of reaching Somali parents through outreach programs in the schools and day care centers aimed at increasing awareness of Somali children’s growing vulnerability to vaccine-preventable diseases. Bahta et al note:

Finding ways to leverage the respect Somalis have for doctors and other health care professionals is challenging. In studies examining how clinicians can provide effective care to Somali patients, building trust has been identified as important. Two things that contribute to trust that are repeatedly cited in the literature are the availability of a competent interpreter and not feeling rushed by the clinician. Clinic policies such as ensuring that a professional interpreter is available, adding time to appointments when interpreters are needed, and consistently scheduling families with the same clinician can support efforts to build trusting relationships with Somali patients.

At their heart, strategies like these are no different than techniques used with the vaccine-hesitant of any race or nationality, adapted to Somali parents by including an interpreter. There’s one area where the Minnesota Somali community might be a bit different, though:

They also want clear direction from their physicians. Providing parents with options may confuse them. A statement such as, “We can give your child the vaccine today, or if you want, we can wait,” may be perceived by the parent as meaning that the clinician also has reservations about vaccines or thinks that either choice is acceptable. One Somali interpreter described an interaction this way: “When the mother told the doctor that she did not want her child to get the triple-letter vaccine, the doctor said, ‘OK.’” The interpreter was worried that the parent thought the doctor agreed that the MMR vaccine wasn’t needed or that he, too, was worried about its effects.

This is different from American parents, who tend to resent being told too firmly what to do and want to make their own decisions. Again, what this shows is the importance of flexibility in dealing with vaccine hesitant parents and how strategies and messaging, although generally sharing the same broad themes, have to be adapted to the specific population being targeted. It’s also important to remember that Minnesota Somalis are not monolithic. Although anti-MMR views predominate and antivaccine views have become common, there have been (and still are) members of the community who are joining forces with Minnesota health officials to push back.

Unfortunately, progress is likely to be slow, as changing entrenched beliefs is difficult and requires a sustained, targeted effort. In the meantime, the children of the Minnesota Somali community will remain vulnerable to measles and potentially other vaccine-preventable diseases and are likely to serve as the nidus for further outbreaks until the MMR uptake rate can be raised back to what it was in 2004. Remember, it took the UK many years to lift its MMR uptake level back to somewhere near where it was before Wakefield, aided and abetted by the tabloid press, caused the MMR panic. There’s no reason to expect that a similar recovery will take any less time in Minnesota.

Sadly, measles is the gift that keeps on giving, and nobody is better than giving it than Andrew Wakefield and his acolytes. The Somali immigrant community in Minnesota is now finding that out.



from ScienceBlogs http://ift.tt/2pwJnP3

There are many harms attributable to the antivaccine movement and its promotion of antivaccine beliefs. Certainly, the harm those of us who have been combatting antivaccine misinformation fear is the return of vaccine-preventable diseases, which is something we’ve seen in the form of outbreaks, such as the Disneyland measles outbreak two years ago and, in my own state, pertussis outbreaks. The Disneyland outbreak was a wake-up call to California legislators, who in its wake passed SB 277, a law that eliminated personal belief exemptions (PBEs) to school vaccine requirements. Now, only medical exemptions are permitted, and so far the law has worked well. In Michigan, we’re still struggling. The Michigan Department of Health and Human Services issued a new rule that requires parents seeking a PBE to attend an education and counseling session at a local county health office before the PBE is issued. Not surprisingly, local antivaxers are not happy and have managed, by painting this rule as a horrific affront to “freedom” and “parental rights,” to persuade legislators to try to pass a law that would not only revoke the rule and explicitly bar MDHHS from issuing similar rules in the future, but it would prevent local health officers from barring unvaccinated children from school during an outbreak. The law failed to pass the first time it was introduced, but Michigan legislators are nothing if not extremely persistent in pursuing harmful policies, and a new version of the same old bill is again under consideration. It matters not one whit to our stupid legislators that the rule change is starting to work to increase vaccine uptake. Unfortunately, we have a fair number of antivaccine and antivaccine-sympathetic legislators.

Although the antivaccine movement in the US has classically been associated with upper middle class and affluent white people, they are not the ones who are likely to suffer the most when herd immunity breaks down. I’ve written extensively here about how the newest (and perhaps most pernicious) antivaccine conspiracy theory, the so-called “CDC whistleblower” conspiracy theory promoted by Del Bigtree and Andrew Wakefield’s propaganda film disguised as a documentary VAXXED, explicitly targets the African-American community, complete with promotional visits featuring the Nation of Islam going to speak in Compton and being involved in protests outside the CDC. Wakefield, as you recall, is the British gastroenterologist who in 1998 published a case series in The Lancet linking MMR to autism. It has since been retracted and shown to have been fraudulent, and Wakefield has had his UK medical license stripped from him. Unfortunately, that only makes him more of a hero to the antivaccine movement, and he’s spent the last 19 years playing that role to the hilt.

The “CDC whistleblower” conspiracy theory is based on the story of CDC scientist William Thompson, who in 2013 apparently contacted biochemical engineer turned incompetent antivaccine epidemiologist Brian Thompson to vent about a study he co-authored in 2004 that examined whether there was a correlation between vaccination with MMR and subsequent risk of autism. Not surprisingly, the study failed to find a correlation. However, there was one subgroup, African-American boys, in which the unadjusted data showed a 3.4-fold increased risk of autism. (I’m simplifying for space considerations in providing background, obviously; if you want the gory details, read here and here for a contemporaneous account of the origin of a new conspiracy theory, as well as my review of the book Vaccine Whistleblower and Andrew Wakefield’s fraudumentary VAXXED.) Thompson had had disagreements with how the data were presented and how he thought the CDC has “suppressed” the unadjusted data. Unfortunately for him, Thompson didn’t realize that Hooker was recording their conversations, and Andrew Wakefield found out about it. Thus, he became the “CDC whistleblower” who seemingly validated what I like to call the central conspiracy theory of the antivaccine movement, specifically that the CDC “knows” that vaccines cause autism but covered it up. It didn’t matter one whit that the correlation was found only in a small subgroup (African-American boys), but it did matter because African-Americans already have reason to distrust the medical community based on history. The “CDC whistleblower” myth feeds into that sad history, which is why Wakefield loves to invoke the Tuskegee syphilis experiment.

This is also not the first time Andrew Wakefield has targeted people of color with his pseudoscience. By any objective measure, for the most part the CDC whistleblower conspiracy theory and VAXXED have not had much resonance in the African-American community other than in the Nation of Islam and among a handful of parents like Sheila Ealey who really believe vaccines caused their children’s autism. The first time around, unfortunately, Wakefield was much more successful. Now, nearly a decade after he first started targeting the community, they are continuing to suffer measles outbreaks. I will begin with the story as it stands now and then go back and look at how it got to this point. The story takes place among a seemingly unlikely group of people in an unexpected location. It’s also a story that I can’t believe I’ve never blogged about before, given how long it’s been going on.

Measles outbreaks among Somali immigrants in Minnesota

Before I first encountered this story several years ago, I had no idea that there was a large community of Somali immigrants in Hennepin County in Minnesota, but there is. In fact, it’s the largest community of Somali immigrants in the US that began forming over a quarter of a century ago and now numbers in the several tens of thousands. Right now, the community is the center of a new measles outbreak, which is just the latest. From the StarTribune a week ago:

As a registered nurse and a consultant to the Minnesota Department of Health, Asli Ashkir has spent nearly a decade talking with Somali parents about autism, vaccines and the importance of getting their children immunized.

Last week she redoubled her efforts. A measles outbreak in Hennepin County has sickened 12 children — all of them unvaccinated and all of them from Somali families, according to the department — throwing a spotlight on low immunization rates among Somali children.

Now state and county public health workers are doing their best to contact Somali parents and underscore the value of immunization. “I know when parents have facts, they do the best they can to make the right decision,” Ashkir said.

I note that the total number of children sickened had reached 32 by the weekend, and the toll is still growing.

The story shows why the Somali community in the Twin Cities area is so susceptible to measles outbreak. All you have to do is to look at this graph of MMR vaccine uptake by year:

MMR uptake among Somali immigrants in Minnesota: This is the effect of nearly a decade of antivaccine propaganda.

MMR uptake among Somali immigrants in Minnesota: This is the effect of nearly a decade of antivaccine propaganda.

The graph above shows what can only be described as a catastrophic plunge over the course of just one decade in MMR uptake among American-born children of Somali descent, from 92% to 42%. There is, for all intents and purposes, no herd immunity in this community. The interesting thing here, though, is that this plunge is very specific. It’s noted in the story that there is not a fear of vaccination in general among the Somali immigrant population. Rather, it’s fear of just one shot: the MMR. It is a fear that antivaxers stoked, beginning sometime around 2008, and they have unfortunately been wildly successful in inculcating fear of the MMR in Somalis in Minnesota. Indeed, a 2014 study examined attitudes towards the MMR vaccine in Somali and non-Somali children in Minnesota and found:

Somali parents were more likely than non-Somali parents to have refused the MMR vaccine for their child (odds ratio, 4.6; 95% confidence interval, 1.2–18.0). Most of them refused vaccines because they had heard of adverse effects associated with the vaccine or personally knew someone who suffered an adverse effect. Somali parents were significantly more likely to believe that autism is caused by vaccines (35% vs. 8% of non-Somali parents). Somalis were also more likely to be uncomfortable with administering multiple vaccines at one visit (odds ratio, 4.0; 95% confidence interval, 1.4–11.9) and more likely to believe that children receive too many vaccines.

It was a small survey, but it was the only one I found in the peer-reviewed medical literature thus far. Its results are not surprising, however, to anyone directly involved with the Somali community, particularly public health officials. There haven’t (yet) been studies published about this latest measles outbreak, but there was a study about the 2011 measles outbreak in Minnesota, which, to that point, was the largest such outbreak in 20 years, with 21 cases identified. Its conclusions were also unsurprising. The source was found to be a 30-month-old US-born child of Somali descent infected while visiting Kenya and then spread to the Somali and non-Somali population primarily through the unvaccinated:

Three case-patients had unknown vaccination status, 1 was vaccinated before the recommended age (11 months), and 1 was a health care worker who was thought to be immune (IgG-positive documented >10 years previously). Sixteen of 21 (76%) were unvaccinated; 7 of 16 (44%) were too young for routine vaccination. Nine (56%) children were age-eligible for routine vaccination but unvaccinated, 7 because of safety concerns owing to the misinformation that MMR vaccine causes autism; 6 of these children were of Somali descent. Two other children did not refuse but were behind on immunizations.

This is how the outbreak spread:

This outbreak began with an unvaccinated US-born child who was exposed to measles in an endemic region of Africa and developed disease on return to the United States. Low vaccination rates in the local Somali community, and subsequent exposures among susceptible homeless shelter residents, fueled ongoing transmission of measles. Delay of the source case-patient’s measles diagnosis also may have contributed to transmission before public health interventions. Although post-exposure prophylaxis, vaccination, and voluntary isolation and quarantine were implemented after the first known case, there was ongoing transmission in 1 of the 2 affected shelters. This transmission was attributable to several factors, including exposures that occurred before the first identified case, an exposure of an infant too young for MMR vaccine according to the routine schedule, as well as exposure of an infant who was too young for the early MMR vaccine outbreak recommendation. Other contributing factors were caused by the challenges of quickly assessing and documenting immune status in a large group of individuals living in a temporary, communal setting. These challenges allowed transmission to individuals who initially were assumed to be immune, but who lacked documentation. After ongoing transmission was seen, immune status testing was implemented for those who lacked documentation.

Notably, two-thirds of the cases in this outbreak were hospitalized, and many of these were hospitalized for respiratory complications in addition to dehydration, highlighting that measles is a severe infection even in well-resourced countries.

If measles is as harmless as antivaxers claim that it is, then why were two-thirds of the people stricken with measles in this outbreak hospitalized for complications? That’s a rhetorical question for antivaxers, obviously.

The first question that faces Minnesota public health officials is, of course: How did we get here? The second is: What can be done to combat MMR fear-mongering? I can’t help but note that the fear of the MMR that is so prevalent among Somali immigrants in Minnesota, while primarily about the MMR, is bleeding over to other vaccines. Some Somali immigrants are starting to show susceptibility to the “too many too soon” myth and, as a result, spacing out the remaining vaccines other than the MMR that they are willing to administer to their children, believing that early vaccination can “damage an infant’s language skills.” Basically, if you live in Minnesota, combatting antivaccine and anti-MMR views in the Somali immigrant community is imperative. Even if you don’t live there, given that the Twin Cities area is a hub of national and international transportation, measles could be as short as a quick plane flight to where you live.

So let’s look at how we got here. Andrew Wakefield has his fingerprints all over this, but it didn’t start with him. As is his usual MO, he opportunistically took advantage of a situation, as he did when he discovered that Brian Hooker had been recording telephone conversations with a disgruntled CDC scientist.

2008: Autism in the Somali immigrant community

The story of how the myth that MMR causes autism became so firmly entrenched among Somalis living in Minnesota began sometime around 2008, with a cluster of autism cases among the community and a news story, as described by Bahta et al. in Minnesota Medicine:

Parents in Minnesota’s Somali community have voiced concern that their children are disproportionately affected by autism spectrum disorder (ASD) compared with children of other ethnicities. Many in the community blame the MMR vaccine. In an August 2008 news story on WCCO-TV, one parent was quoted as saying, “It’s the vaccines.”

Shortly after the story aired, the Minnesota Department of Health reached out to members of the Somali community to gather more information. Health department staff attended meetings with Somali parents, many of whom were unfamiliar with ASD. Repeatedly, they stated that they don’t even have a word for autism in their language. In telling her story, one mother reported that in their attempt to understand ASD, she and others discovered groups that supported the claim that vaccines, particularly MMR, cause autism. Misinformation can spread rapidly in the Somali community, which has a rich oral tradition of passing information to one another. It is now widely accepted among Somali Minnesotans that MMR is to blame for autism.

The antivaccine movement was all over this story in 2008. For example, David Kirby, author of the book Evidence of Harm: Mercury in Vaccines and the Autism Epidemic: A Medical Controversy, which was one of the early works using pseudoscience to link thimerosal in vaccines to autism was writing articles like ‘Autism May Be Caused By “Chemical Exposures”‘ specifically about the Somali community in Minnesota, with a “wink, wink, nudge, nudge” that the “idea that ‘chemical exposures’ (vaccine related or otherwise) might cause autism still brings virtual apoplexia to certain scientific circles.” He had previously hammered the same theme on the antivaccine blog Age of Autism, noting from the data presented that “rate of autism among Somali children in the public schools had been reported at 1 in 28 kids” and that the “80 or so Somali parents who attended were disappointed, by all accounts, that Dr. Punyko had no way to tell them if autism among their children was, as they strongly suspect, more common than among non-Somalis the same age.”

But was autism more than twice as common among the American-born children of Somali immigrants, as the data linked to above suggest? In early 2009, the Minnesota Department of Health released a study of autism among Somali immigrants. It is a substantial read. Here are a couple of key findings, which, as is often the case in studies of autism compared to parental perception of autism prevalence, are not as clear as the prevalent belief among the Somali community in Minnesota or as the antivaccine movement latched onto:

  • The administrative prevalence for three and four year old Somali children was significantly higher than for non-Somali children. This is consistent with the perceptions of the community that a larger number of Somali children were participating in ASD programs. Because of the study’s limitations, it is not proof that more Somali children have autism than other children; however, it does raise an important question about why Somali children are participating in this program more than other children.
  • The relative difference between Somali and non-Somali administrative prevalence decreased markedly over the three years covered by the study. It is unclear if this is an identification issue, a change in parental awareness for the need for developmental screening or some other issue.
  • Administrative prevalence rates for the Asian and Native American groups were found to be “strikingly low.” The reasons for these low rates are unknown, but they could be important to understanding whether the rate of ASD is higher among Somali children or underestimated among other children. In other words, the seemingly low prevalence rate among Asian and Native American children may artificially boost the comparative rate among Somali children, distorting a true understanding of all groups involved.

So, yes, administrative prevalence of autism was higher among Somali-Americans in Minnesota, but there were a lot of issues that made it difficult to use these data to determine for sure whether actual autism prevalence was higher, not the least of which was that as was noted in Left Brain, Right Brain, Department of Education data are not reliable for tracking autism. Jim Laidler made the same point in a publication in Pediatrics in 2005. Indeed, the most recent study of autism in the Somali-American community in Minneapolis was published in 2016 and found that Somali children were as likely to be identified with an autism spectrum disorder (ASD) as white children but that Somali children with ASD were significantly more likely to have an intellectual disability than children with ASD in all other racial and ethnic groups. Meanwhile, Steve Novella examined the cluster and proposed other potential causes for it, if even there was a cluster, such as vitamin D deficiency or a founder effect. Of course, as I pointed out above, it appears that children born to Somali immigrants are no more likely to be diagnosed with autism than white children; so there wasn’t even a cluster there. Unfortunately, it took eight years to figure that out.

By long before then, the damage had been done and the seed of distrust in the MMR and other vaccines had been planted by antivaxers. Over the next several years, as you will see, antivaxers nurtured that seed until it blossomed in the form of measles outbreaks.

Enter Andrew Wakefield

It’s not clear exactly when Andrew Wakefield first made contact with the Minnesota Somali community, but I do know that Age of Autism was on the case as early as August 2008 and that the founder of the antivaccine group Generation Rescue J.B. Handley published “An Open Letter to the Somali Parents of Minnesota” in which he told them it was the vaccines and that they can’t trust the local health authorities. He even went so far as to urge them to declare a “state of emergency within your community and create a new vaccine schedule for your kids.” Meanwhile, also as early as August 2008, David Kirby had been writing stories like ‘Is Autism an “American Disease?” Somali Immigrants Reportedly Have High Rates.’

I do know for sure from media accounts and triumphant blog posts in Age of Autism that he met multiple times with the community and its leaders between 2010 and 2011 and that he appears to be still intermittently in contact. For instance, here is one contemporaneous account in local media from 2010. It was a time when he proposed as “study” of autism in Somali immigrants and promised to raise funds for it, something he appears never to have done. At the same time he sold the study this way:

Minnesota Somalis worried about autism rates among their children recently invited controversial British researcher Andrew Wakefield to Minneapolis to talk to their community.

At a Somali community meeting in Minneapolis, Wakefield asked his audience to participate in a study. He told about a hundred people gathered at a Somali-owned restaurant that they could help find the cause of autism.

“It is solvable, it has a cause, it had a beginning and it must have an end,” Wakefield said. “We cannot accept the damage that is being done to all of these children. It is completely unacceptable and the suffering you’re going through.”

At the same talk, Wakefield claimed that there were no known cases of autism in Somalia, characterized in the story as an “anecdotal observation many Somalis confirm.” It staggers the mind that Wakefield would make such a claim (OK, actually, it doesn’t, given how big a liar Wakefield is), but it does not stagger the mind that Minnesota Somalis would find such a claim credible. Somalia is a poor country, and it does not stretch the imagination to speculate that most people living there are unfamiliar with autism. Nor does it bend credibility too much to observe that a Third World country is unlikely to have the same sort of screening and support programs for autism that we have in the US and other developed countries and that in such countries most cases of autism other than the most severe would go undiagnosed. Indeed, even the severe cases might well be diagnosed as mental retardation rather than autism.

Be that as it may, the cluster of autism in 2008 led to perceptions like this one:

She recalled a Somali mother who spoke at a public health meeting at the Brian Coyle Community Center some years ago. She had given birth to several healthy children in Africa, but her first child in the United States showed autism symptoms at an early age.

Wakefield visited Minneapolis again right in the middle of the 2011 measles outbreak to give a talk at a Somali restaurant. It was noted at the time that there were “a number of vocal pediatricians and doctors of Somali descent trying to speak out about this” but that distrust of health authorities was very high and local antivaccine groups like the Vaccine Safety Council of Minnesota were actively influencing Somalis. They still are. In 2016, for instance, the VSCM board member Patti Carroll published a warning to Somali parents that the Minnesota Department of Health “schools professionals to persuade Somali parents to give their children the MMR vaccine, despite clear opposition.”

Gee, you say that as though it were a bad thing.

That’s the problem, of course. Antivaxers are opportunistic in the extreme. If they see a population who are vulnerable to their disease-promoting message, they will pounce, and it’s always about the vaccines. They saw a story of a possible autism cluster among the children of Somali immigrants in Minnesota. Where scientists see such a story and ask “Is the cluster real and not spurious?” and “If it’s real, what might be causing it?” antivaxers see such a story and assume it absolutely, positively must be the vaccines. In this particular case, they took advantage of a newly arrived immigrant community’s lack of knowledge about autism and vaccines, its tradition in which information is primarily transmitted orally, and the distrust some of its members had for the local health authorities. The results are still playing out in catastrophically low MMR uptake and measles outbreaks.

Over the weekend, it got even worse, as a coalition of antivaccine groups gathered together to tell the Somali immigrant population that the “the epidemic is autism, not measles”:

As Minnesota confronts its second measles outbreak in seven years, public health officials are battling to contain the disease while also trying to educate parents in the face of an organized opposition.

As happened in 2011, anti-vaccine activists are reaching out to Minnesota’s Somali community, where both outbreaks have been centered, with messages that reinforce the discredited belief that vaccines cause autism.

On Sunday afternoon, a coalition of anti-vaccine organizations plans a meeting at the Brian Coyle Community Center on Minneapolis’ West Bank in an effort to bring their message to Somali families, saying “The epidemic is autism, not measles.”

Just what the Minnesota Somali immigrant community needs.

What can be done?

As every source I’ve read over the years about the Minnesota Somali community and vaccines has stated, suspicion and fear of the MMR vaccine are now very much entrenched and will be very difficult to reverse. Indeed, it’s been pointed out:

Minnesota Department of Health staff found that fear of autism was often the reason for parents’ refusal to have their children vaccinated. Highly educated Somali Minnesotans are not exempt from this fear. As one Somali educator admitted, “My children did not get the MMR; my evidence is the Somali children I see who have autism.”

Parents who cited fear of autism as the reason for their vaccine hesitancy told health department staff that they received their information mostly from other Somali Minnesotans. Being told that MMR does not cause autism was not satisfactory for many parents because no one could tell them what does cause autism. Yet, when asked whom they would trust for health information, nearly all said they trusted their health care provider. And a significant number who refused vaccinations said they would reconsider their decision if they were given more information.

Parents of children diagnosed with ASD were articulate about their belief in an association between MMR and autism and sometimes also implicated receipt of multiple vaccines as the cause of their child’s autism. Some Somali parents have come to realize that autism and vaccines are unrelated, but they are in the minority.

Vaccine hesitant Somali parents thus resemble our own native-grown antivaxers and vaccine hesitant parents in many ways. Many are highly intelligent and educated. They get their misinformation about vaccines and autism from their peers more than from medical authorities. Also, it is the parents who have children diagnosed with ASD who are the most passionate and persuasive in arguing that vaccines are linked with autism, and, because of the low rate of measles (thanks to the MMR) many Somali parents view autism as a greater threat to their children than the measles and base their decisions about vaccines on that misperception. One difference is that, unlike many of our native antivaxers, Somali immigrants generally hold the medical profession in high esteem and are thus more open to being influenced by physicians and other clinicians. Actually, I should be a bit more clear. American antivaxers generally distrust the medical profession, while American parents who are vaccine-hesitant tend to hold the medical profession in higher esteem.

Be that as it may the Minnesota Department of Health has been trying to meet the challenge of reaching Somali parents through outreach programs in the schools and day care centers aimed at increasing awareness of Somali children’s growing vulnerability to vaccine-preventable diseases. Bahta et al note:

Finding ways to leverage the respect Somalis have for doctors and other health care professionals is challenging. In studies examining how clinicians can provide effective care to Somali patients, building trust has been identified as important. Two things that contribute to trust that are repeatedly cited in the literature are the availability of a competent interpreter and not feeling rushed by the clinician. Clinic policies such as ensuring that a professional interpreter is available, adding time to appointments when interpreters are needed, and consistently scheduling families with the same clinician can support efforts to build trusting relationships with Somali patients.

At their heart, strategies like these are no different than techniques used with the vaccine-hesitant of any race or nationality, adapted to Somali parents by including an interpreter. There’s one area where the Minnesota Somali community might be a bit different, though:

They also want clear direction from their physicians. Providing parents with options may confuse them. A statement such as, “We can give your child the vaccine today, or if you want, we can wait,” may be perceived by the parent as meaning that the clinician also has reservations about vaccines or thinks that either choice is acceptable. One Somali interpreter described an interaction this way: “When the mother told the doctor that she did not want her child to get the triple-letter vaccine, the doctor said, ‘OK.’” The interpreter was worried that the parent thought the doctor agreed that the MMR vaccine wasn’t needed or that he, too, was worried about its effects.

This is different from American parents, who tend to resent being told too firmly what to do and want to make their own decisions. Again, what this shows is the importance of flexibility in dealing with vaccine hesitant parents and how strategies and messaging, although generally sharing the same broad themes, have to be adapted to the specific population being targeted. It’s also important to remember that Minnesota Somalis are not monolithic. Although anti-MMR views predominate and antivaccine views have become common, there have been (and still are) members of the community who are joining forces with Minnesota health officials to push back.

Unfortunately, progress is likely to be slow, as changing entrenched beliefs is difficult and requires a sustained, targeted effort. In the meantime, the children of the Minnesota Somali community will remain vulnerable to measles and potentially other vaccine-preventable diseases and are likely to serve as the nidus for further outbreaks until the MMR uptake rate can be raised back to what it was in 2004. Remember, it took the UK many years to lift its MMR uptake level back to somewhere near where it was before Wakefield, aided and abetted by the tabloid press, caused the MMR panic. There’s no reason to expect that a similar recovery will take any less time in Minnesota.

Sadly, measles is the gift that keeps on giving, and nobody is better than giving it than Andrew Wakefield and his acolytes. The Somali immigrant community in Minnesota is now finding that out.



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May guide to the bright planets

Coming soon! Look for the bright waxing gibbous moon to swing by the brilliant planet Jupiter on May, 6, 7 and 8. Read more.

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Three of the 5 five bright planets are easy to see in the May 2017 night sky: Jupiter, Saturn and Venus. Jupiter appears first thing at dusk and shines nearly all night long. Saturn rises into the southeast sky at mid-to-late evening and then stays out for rest of the night. Venus rises over the eastern horizon as the predawn darkness is giving way to morning dawn. Mars and Mercury present more of a challenge this month, as Mars is somewhat obscured by evening dusk and Mercury by morning dawn. Follow the links below to learn more about the planets in May 2017.

Mercury, below Venus, low in east before sunrise

Mars fading into western evening twilight

Bright Jupiter rules the nighttime

Saturn from late evening till dawn

Venus, brilliant in east at morning dawn

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Visit a new EarthSky feature – Best Places to Stargaze – and add your fav.

Wow! Wonderful shot of Mercury – over the Chilean Andes – January 2017, from Yuri Beletsky Nightscapes.

From northerly latitudes, Mercury is found to the lower left of the brilliant planet Venus. From the Southern Hemisphere, look for Mercury about the same distance from Venus but more directly below. Read more.

Mercury, below Venus, low in east before sunrise. When we say that Mercury is low in the east before sunrise, we’re really talking about the Northern Hemisphere. For the Southern Hemisphere, May 2017 presents the best showing of Mercury in the morning sky for the year. (For northerly latitudes, this is least favorable apparition of Mercury in the morning sky in 2017.) For much of the Southern Hemisphere, Mercury actually comes up before dawn’s first light all month long; in the Northern Hemisphere, Mercury rises a short while before sunrise and sits low in the glare of morning twilight throughout May 2017.

Mercury is tricky. If you look too soon before sunrise, Mercury will still be below the horizon; if you look too late, it will obscured by the morning twilight. Watch for Mercury low in the sky, and near the sunrise point on the horizon, being mindful of Mercury’s rising time.

Binoculars are always helpful for any Mercury search. Use them to scan along the eastern horizon until a starlike point – deep in the twilight – comes into view. Mercury is bright, but it’s always near the sunset or sunrise. Thus you have to search for it.

If you live in the Southern Hemisphere, this is your month! A super apparition of Mercury take places in the morning sky throughout May of 2017.

Watch for the slender waning crescent moon to pair up with Mercury on or near May 23.

Click here for recommended almanacs; they can give you Mercury’s rising time in your sky.

Let the young moon guide you to Mars’ place in the sky on May 26 and 27. You may need binoculars to see Mars in the glare of evening twilight. Read more.

Mars fading into western evening twilight. After appearing as a fiery red light last year – in May and June 2016 – Mars is now a fading ember of its former self. Look for Mars rather low in the west as soon as darkness begins to fall. Mars is edging closer to the sunset day by day. It’ll disappear in the glare of evening dusk by June 2017.

Because Earth is traveling faster in its orbit than Mars is, Earth’s distance from Mars is increasing by the day. So there are two reasons for Mars’ disappearing act this month. Its increasing distance from Earth means Mars’ brightness is decreasing daily. Plus, Mars is setting sooner after the sun with each passing day. The fading planet is sinking closer to glare of sunset, soon to disappear from the evening sky.

From mid-northern latitudes (U.S. and Europe), look for the red planet Mars to set in the west around nightfall in early May, and a bit more than one hour after sunset by the month’s end. The same holds true for mid-southern latitudes (Australia and South Africa).

Let the waxing crescent moon help guide you to Mars on May 26. This will probably be your last chance to catch the young waxing crescent moon and Mars coupling up together in the evening sky this year. You may need binoculars to see Mars in the glow of evening dusk.

Mars won’t make its official transition from the evening to morning sky until July 27, 2017. It’ll emerge in the east before dawn in late September or October 2017. The conjunction of Mars and Venus on October 5, 2017, might well be the first time most people notice the red planet in the morning sky.

Looking for a sky almanac? EarthSky recommends…

Look for the bright waxing gibbous moon to beam close to Jupiter on May, 6, 7 and 8. Read more.

Bright Jupiter rules the nighttime. Jupiter reached opposition on April 7 and came closest to Earth for the year on April 8. Although Jupiter shone at its brightest best for all of 2017 in April, it’ll still be blazing away in May! Jupiter beams as the third-brightest celestial body in the nighttime sky, after the moon and Venus. Yet Jupiter shines from dusk until the wee hours of the morning whereas Venus only appears in the morning sky. In fact, this month will find Jupiter setting in the west at roughly the same time that Venus rises in the east.

Click here for an almanac telling you Jupiter’s setting time and Venus’ rising time in your sky.

Watch for a bright waxing gibbous moon to join up with Jupiter for several days, centered on or near May 6. See the above sky chart. Wonderful sight!

From around the world, Jupiter appears in the east to southeast sky first thing at dusk. It crosses the sky during the night, to set in the west to southwest at or near dawn.

Jupiter shines in front of the constellation Virgo, near Virgo’s sole 1st-magnitude star, Spica.

Fernando Roquel Torres in Caguas, Puerto Rico captured Jupiter, the Great Red Spot (GRS) and all 4 of its largest moons – the Galilean satellites – on the date of Jupiter’s 2017 opposition (April 7).

If you have binoculars or a telescope, it’s fairly easy to see Jupiter’s four major moons, which look like pinpricks of light on or near the same plane. They are often called the Galilean moons to honor Galileo, who discovered these great Jovian moons in 1610. In their order from Jupiter, these moons are Io, Europa, Ganymede and Callisto.

These moons circle Jupiter around the Jovian equator. In cycles of six years, we view Jupiter’s equator edge-on. So, in 2015, we got to view a number of mutual events involving Jupiter’s moons through a high-powered telescope. Click here or here or here for more details.

Although Jupiter’s axial tilt is only 3o out of perpendicular relative to the ecliptic (Earth’s orbital plane), Jupiter’s axis will tilt enough toward the sun and Earth so that the farthest of these four moons, Callisto, won’t pass in front of Jupiter or behind Jupiter for a period of about three years, starting in late 2016. During this approximate 3-year period, Callisto will remain “perpetually” visible, alternately swinging “above” and “below” Jupiter.

Click here for a Jupiter’s moons almanac, courtesy of Sky & Telescope.

Watch for the waning gibbous moon to pass close to the star Antares and the planet Saturn on May 11, 12 and 13. Read more.

Saturn from late evening till dawn. Saturn is getting close to its June 15 opposition and is now appearing the evening sky.

From mid-northern latitudes, Saturn rises in the southeast sky somewhere around 10 to 11 p.m. local time (11 p.m. to midnight daylight-saving time) in early May 2017. By the month’s end, Saturn is up by late dusk or nightfall.

At temperate latitudes in the Southern Hemisphere, Saturn rises around mid-evening (8:30 to 9:30 p.m. local time), and by the month’s end, Saturn rises at late dusk or nightfall.

But your best view of Saturn, from either the Northern or Southern Hemisphere, is still during the wee hours before dawn. That’s when Saturn climbs highest up for the night. Click here to find out Saturn’s transit time (when Saturn soars highest up for the night).

Be sure to let the waning crescent moon guide you to Saturn (and the nearby star Antares) for several days, centered on or near May 13.

Saturn, the farthest world that you can easily view with the eye alone, appears golden in color. It shines with a steady light.

Binoculars don’t reveal Saturn’s gorgeous rings, by the way, although binoculars will enhance Saturn’s golden color. To see the rings, you need a small telescope. A telescope will also reveal one or more of Saturn’s many moons, most notably Titan.

Saturn’s rings are inclined at nearly 27o from edge-on, exhibiting their northern face. In October 2017, the rings will open most widely, displaying a maximum inclination of 27o.

As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In the year 2025, the rings will appear edge-on as seen from Earth. After that, we’ll begin to see the south side of Saturn’s rings, to increase to a maximum inclination of 27o by May 2032.

Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

Jenney Disimon in Sabah, Borneo captured Venus before dawn on April 8, 2017.

Watch for the waning crescent moon to swing by Venus on the mornings of May 21, 22 and 23. Read more.

Venus, brilliant in east at morning dawn In the first three weeks of March 2017, Venus shone in the west after sunset. In late March, Venus entered our morning sky, passing between the sun and Earth on March 25. Venus then reached its greatest illuminated extent in the morning sky on April 30. This dazzling world will still be at or near its peak brilliance as the morning “star” in early May 2017.

So it’s brightest in the morning sky in late April and early May, but … Venus is always brilliant and beautiful, the brightest celestial body to light up our sky besides the sun and moon. If you’re an early bird, you can count on Venus to be your morning companion for many months to come.

Enjoy the picturesque coupling of the waning crescent moon and Venus in the eastern sky before sunrise on or near May 22.

From mid-northern latitudes (U.S. and Europe), Venus rises nearly two hours before sunrise in early May, and by the month’s end, Venus comes up a little more than two hours before the sun.

At mid-southern latitudes (Australia and South Africa), Venus rises about about 3 hours before sunup in early May, and by the end of the month, it comes up nearly 4 hours before sunrise. Venus and Mercury both rise much sooner before the sun in the Southern Hemisphere than they do in the Northern Hemisphere.

Click here for an almanac giving rising time of Venus and Mercury in your sky.

The chart below helps to illustrate why we sometimes see Venus in the evening, and sometimes before dawn.

Earth's and Venus' orbits

The Earth and Venus orbit the sun counterclockwise as seen from earthly north. When Venus is to the east (left) of the Earth-sun line, we see Venus as an evening “star” in the west after sunset. After Venus reaches its inferior conjunction, Venus then moves to the west (right) of the Earth-sun line, appearing as a morning “star” in the east before sunrise.

This month, Jupiter will set in the west at roughly the same time that Venus rises in the east. Next month, in June, Jupiter will set in the west before Venus rises in the east.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

From late January, and through mid-February, 5 bright planets were visible at once in the predawn sky. This image is from February 8, 2016. It's by Eliot Herman in Tucson, Arizona. View on Flickr.

This image is from February 8, 2016. It shows all 5 bright planets at once. Photo by our friend Eliot Herman in Tucson, Arizona.

Skywatcher, by Predrag Agatonovic.

Skywatcher, by Predrag Agatonovic.

Bottom line: In May 2017, three of the five bright planets appear in the evening sky: Mars, Jupiter and Saturn. Venus and Mercury are found exclusively in the morning sky.

Don’t miss anything. Subscribe to EarthSky News by email

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Coming soon! Look for the bright waxing gibbous moon to swing by the brilliant planet Jupiter on May, 6, 7 and 8. Read more.

Our yearly fund-raiser ends May 5! Please donate to help EarthSky keep going.

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Three of the 5 five bright planets are easy to see in the May 2017 night sky: Jupiter, Saturn and Venus. Jupiter appears first thing at dusk and shines nearly all night long. Saturn rises into the southeast sky at mid-to-late evening and then stays out for rest of the night. Venus rises over the eastern horizon as the predawn darkness is giving way to morning dawn. Mars and Mercury present more of a challenge this month, as Mars is somewhat obscured by evening dusk and Mercury by morning dawn. Follow the links below to learn more about the planets in May 2017.

Mercury, below Venus, low in east before sunrise

Mars fading into western evening twilight

Bright Jupiter rules the nighttime

Saturn from late evening till dawn

Venus, brilliant in east at morning dawn

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Visit a new EarthSky feature – Best Places to Stargaze – and add your fav.

Wow! Wonderful shot of Mercury – over the Chilean Andes – January 2017, from Yuri Beletsky Nightscapes.

From northerly latitudes, Mercury is found to the lower left of the brilliant planet Venus. From the Southern Hemisphere, look for Mercury about the same distance from Venus but more directly below. Read more.

Mercury, below Venus, low in east before sunrise. When we say that Mercury is low in the east before sunrise, we’re really talking about the Northern Hemisphere. For the Southern Hemisphere, May 2017 presents the best showing of Mercury in the morning sky for the year. (For northerly latitudes, this is least favorable apparition of Mercury in the morning sky in 2017.) For much of the Southern Hemisphere, Mercury actually comes up before dawn’s first light all month long; in the Northern Hemisphere, Mercury rises a short while before sunrise and sits low in the glare of morning twilight throughout May 2017.

Mercury is tricky. If you look too soon before sunrise, Mercury will still be below the horizon; if you look too late, it will obscured by the morning twilight. Watch for Mercury low in the sky, and near the sunrise point on the horizon, being mindful of Mercury’s rising time.

Binoculars are always helpful for any Mercury search. Use them to scan along the eastern horizon until a starlike point – deep in the twilight – comes into view. Mercury is bright, but it’s always near the sunset or sunrise. Thus you have to search for it.

If you live in the Southern Hemisphere, this is your month! A super apparition of Mercury take places in the morning sky throughout May of 2017.

Watch for the slender waning crescent moon to pair up with Mercury on or near May 23.

Click here for recommended almanacs; they can give you Mercury’s rising time in your sky.

Let the young moon guide you to Mars’ place in the sky on May 26 and 27. You may need binoculars to see Mars in the glare of evening twilight. Read more.

Mars fading into western evening twilight. After appearing as a fiery red light last year – in May and June 2016 – Mars is now a fading ember of its former self. Look for Mars rather low in the west as soon as darkness begins to fall. Mars is edging closer to the sunset day by day. It’ll disappear in the glare of evening dusk by June 2017.

Because Earth is traveling faster in its orbit than Mars is, Earth’s distance from Mars is increasing by the day. So there are two reasons for Mars’ disappearing act this month. Its increasing distance from Earth means Mars’ brightness is decreasing daily. Plus, Mars is setting sooner after the sun with each passing day. The fading planet is sinking closer to glare of sunset, soon to disappear from the evening sky.

From mid-northern latitudes (U.S. and Europe), look for the red planet Mars to set in the west around nightfall in early May, and a bit more than one hour after sunset by the month’s end. The same holds true for mid-southern latitudes (Australia and South Africa).

Let the waxing crescent moon help guide you to Mars on May 26. This will probably be your last chance to catch the young waxing crescent moon and Mars coupling up together in the evening sky this year. You may need binoculars to see Mars in the glow of evening dusk.

Mars won’t make its official transition from the evening to morning sky until July 27, 2017. It’ll emerge in the east before dawn in late September or October 2017. The conjunction of Mars and Venus on October 5, 2017, might well be the first time most people notice the red planet in the morning sky.

Looking for a sky almanac? EarthSky recommends…

Look for the bright waxing gibbous moon to beam close to Jupiter on May, 6, 7 and 8. Read more.

Bright Jupiter rules the nighttime. Jupiter reached opposition on April 7 and came closest to Earth for the year on April 8. Although Jupiter shone at its brightest best for all of 2017 in April, it’ll still be blazing away in May! Jupiter beams as the third-brightest celestial body in the nighttime sky, after the moon and Venus. Yet Jupiter shines from dusk until the wee hours of the morning whereas Venus only appears in the morning sky. In fact, this month will find Jupiter setting in the west at roughly the same time that Venus rises in the east.

Click here for an almanac telling you Jupiter’s setting time and Venus’ rising time in your sky.

Watch for a bright waxing gibbous moon to join up with Jupiter for several days, centered on or near May 6. See the above sky chart. Wonderful sight!

From around the world, Jupiter appears in the east to southeast sky first thing at dusk. It crosses the sky during the night, to set in the west to southwest at or near dawn.

Jupiter shines in front of the constellation Virgo, near Virgo’s sole 1st-magnitude star, Spica.

Fernando Roquel Torres in Caguas, Puerto Rico captured Jupiter, the Great Red Spot (GRS) and all 4 of its largest moons – the Galilean satellites – on the date of Jupiter’s 2017 opposition (April 7).

If you have binoculars or a telescope, it’s fairly easy to see Jupiter’s four major moons, which look like pinpricks of light on or near the same plane. They are often called the Galilean moons to honor Galileo, who discovered these great Jovian moons in 1610. In their order from Jupiter, these moons are Io, Europa, Ganymede and Callisto.

These moons circle Jupiter around the Jovian equator. In cycles of six years, we view Jupiter’s equator edge-on. So, in 2015, we got to view a number of mutual events involving Jupiter’s moons through a high-powered telescope. Click here or here or here for more details.

Although Jupiter’s axial tilt is only 3o out of perpendicular relative to the ecliptic (Earth’s orbital plane), Jupiter’s axis will tilt enough toward the sun and Earth so that the farthest of these four moons, Callisto, won’t pass in front of Jupiter or behind Jupiter for a period of about three years, starting in late 2016. During this approximate 3-year period, Callisto will remain “perpetually” visible, alternately swinging “above” and “below” Jupiter.

Click here for a Jupiter’s moons almanac, courtesy of Sky & Telescope.

Watch for the waning gibbous moon to pass close to the star Antares and the planet Saturn on May 11, 12 and 13. Read more.

Saturn from late evening till dawn. Saturn is getting close to its June 15 opposition and is now appearing the evening sky.

From mid-northern latitudes, Saturn rises in the southeast sky somewhere around 10 to 11 p.m. local time (11 p.m. to midnight daylight-saving time) in early May 2017. By the month’s end, Saturn is up by late dusk or nightfall.

At temperate latitudes in the Southern Hemisphere, Saturn rises around mid-evening (8:30 to 9:30 p.m. local time), and by the month’s end, Saturn rises at late dusk or nightfall.

But your best view of Saturn, from either the Northern or Southern Hemisphere, is still during the wee hours before dawn. That’s when Saturn climbs highest up for the night. Click here to find out Saturn’s transit time (when Saturn soars highest up for the night).

Be sure to let the waning crescent moon guide you to Saturn (and the nearby star Antares) for several days, centered on or near May 13.

Saturn, the farthest world that you can easily view with the eye alone, appears golden in color. It shines with a steady light.

Binoculars don’t reveal Saturn’s gorgeous rings, by the way, although binoculars will enhance Saturn’s golden color. To see the rings, you need a small telescope. A telescope will also reveal one or more of Saturn’s many moons, most notably Titan.

Saturn’s rings are inclined at nearly 27o from edge-on, exhibiting their northern face. In October 2017, the rings will open most widely, displaying a maximum inclination of 27o.

As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In the year 2025, the rings will appear edge-on as seen from Earth. After that, we’ll begin to see the south side of Saturn’s rings, to increase to a maximum inclination of 27o by May 2032.

Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

Jenney Disimon in Sabah, Borneo captured Venus before dawn on April 8, 2017.

Watch for the waning crescent moon to swing by Venus on the mornings of May 21, 22 and 23. Read more.

Venus, brilliant in east at morning dawn In the first three weeks of March 2017, Venus shone in the west after sunset. In late March, Venus entered our morning sky, passing between the sun and Earth on March 25. Venus then reached its greatest illuminated extent in the morning sky on April 30. This dazzling world will still be at or near its peak brilliance as the morning “star” in early May 2017.

So it’s brightest in the morning sky in late April and early May, but … Venus is always brilliant and beautiful, the brightest celestial body to light up our sky besides the sun and moon. If you’re an early bird, you can count on Venus to be your morning companion for many months to come.

Enjoy the picturesque coupling of the waning crescent moon and Venus in the eastern sky before sunrise on or near May 22.

From mid-northern latitudes (U.S. and Europe), Venus rises nearly two hours before sunrise in early May, and by the month’s end, Venus comes up a little more than two hours before the sun.

At mid-southern latitudes (Australia and South Africa), Venus rises about about 3 hours before sunup in early May, and by the end of the month, it comes up nearly 4 hours before sunrise. Venus and Mercury both rise much sooner before the sun in the Southern Hemisphere than they do in the Northern Hemisphere.

Click here for an almanac giving rising time of Venus and Mercury in your sky.

The chart below helps to illustrate why we sometimes see Venus in the evening, and sometimes before dawn.

Earth's and Venus' orbits

The Earth and Venus orbit the sun counterclockwise as seen from earthly north. When Venus is to the east (left) of the Earth-sun line, we see Venus as an evening “star” in the west after sunset. After Venus reaches its inferior conjunction, Venus then moves to the west (right) of the Earth-sun line, appearing as a morning “star” in the east before sunrise.

This month, Jupiter will set in the west at roughly the same time that Venus rises in the east. Next month, in June, Jupiter will set in the west before Venus rises in the east.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

From late January, and through mid-February, 5 bright planets were visible at once in the predawn sky. This image is from February 8, 2016. It's by Eliot Herman in Tucson, Arizona. View on Flickr.

This image is from February 8, 2016. It shows all 5 bright planets at once. Photo by our friend Eliot Herman in Tucson, Arizona.

Skywatcher, by Predrag Agatonovic.

Skywatcher, by Predrag Agatonovic.

Bottom line: In May 2017, three of the five bright planets appear in the evening sky: Mars, Jupiter and Saturn. Venus and Mercury are found exclusively in the morning sky.

Don’t miss anything. Subscribe to EarthSky News by email

Enjoy knowing where to look in the night sky? Please donate to help EarthSky keep going.

Rather donate via PayPal or send a check? Click here.



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Comments of the Week #158: from event horizons to time travel [Starts With A Bang]

“Time travel used to be thought of as just science fiction, but Einstein’s general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out.” -Stephen Hawking

As always, there’s been a new fantastic week of articles here at Starts With A Bang, punctuated by our new podcast this month, on the physics of time travel!


Have a listen (or download it and take it with you) and thank our Patreon supporters for making it possible! Now, what was this past week all about? Come enjoy some fabulous stories if you missed anything, including:

There’s always so much more I could have talked about or so many more details I could have gone into but didn’t, and that’s what makes doing a follow-up so informative and educational. So let’s jump into what you wanted to learn or discuss more about here, and enjoy our comments of the week!

Image credit: Mark Garlick / SPL.

Image credit: Mark Garlick / SPL.

From Michael Mooney on his ‘key issues’ with relativity: “I am sorry that you refuse to address the core of the issue I bring to your forum.
Is there a “real world” independent of observation or not? (Yes, there is.)
Does the Earth physically change dimensions when (if ever) viewed from near light speed or not? (Ans: Not)
Does Earth’s atmosphere physically change in depth/height “for” every incoming muon or not? (Ans: Not.)”

When I “refuse to address” your issue it’s because you are asking a question that doesn’t have a scientific answer. I’m not in the business of giving you uninformed opinions and asserting them as facts. So if you want these three questions answered with scientific accuracy, let’s go.

1.) We cannot and have not ever measured the world independent of observation, and will never be able to do so. That is a fundamental limit of being a physical being in a physical Universe. Some things we can not observe for a very long time, then look at them and they will be exactly the same as a deterministic equation predicted. Others, if we observe them continuously, will give different results than if we didn’t look. So is there a “real world” independent of observation? You can’t answer, and I also assert that your quoted phrase “real world” is ambiguously defined.

Moving close to the speed of light results in times and distances transforming, with lengths -- including the length of your starship -- becoming shorter in the direction of motion. Image credit: David Taylor of Northwestern, via http://ift.tt/2m8aTPM.

Moving close to the speed of light results in times and distances transforming, with lengths — including the length of your starship — becoming shorter in the direction of motion. Image credit: David Taylor of Northwestern, via http://ift.tt/2m8aTPM.

2.) Does Earth physically change dimensions when viewed near the speed of light? The answer is yes, dependent on which observer you ask. If I ask you, on Earth, whether Earth’s physical dimensions change, the answer is no. If I ask the traveler whether they do, the answer is yes. There are some things that are invariant under relativistic transformations, but physical extents in space are not one of them.

Cosmic rays shower particles by striking protons and atoms in the atmosphere, but they also emit light due to Cherenkov radiation. Image credit: Simon Swordy (U. Chicago), NASA.

Cosmic rays shower particles by striking protons and atoms in the atmosphere, but they also emit light due to Cherenkov radiation. Image credit: Simon Swordy (U. Chicago), NASA.

3.) Does the Earth’s atmosphere change for every incoming relativistic particle? It’s not a “change,” as you incorrectly use the word, but it achieves a unique size/extent with respect to that particle, defined by that particle’s motion. The size of the atmosphere is entirely dependent on that particle’s frame-of-reference, and there is no definition of size/length/distance/spatial extent independent of reference frame in relativity.

Now, I have stated previously to you that there is an apparent length contraction that is not visually real, and I want you to understand why. If an object is moving close to the speed of light and it is emitting/reflecting photons, the way the object appears will often be uncontracted because of the superimposed effects of length contraction atop the fact that the speed of light is finite and not much greater than the moving object. You can also get visual effects that appear to move faster-than-light, known as photonic booms. But the thing you want to be invariant — the physical size of a physical object — simply isn’t, nor is it well-defined in the absence of an observer.

Image credit: CERN/Maximlien Brice, of the CMS detector, the small detector at the LHC.

Image credit: CERN/Maximlien Brice, of the CMS detector, the small detector at the LHC.

From Elle H.C. on the future of science: “‘Real’ physical testing isn’t going to open any new doors (physics). The future will come from fiddling and experimenting with computer simulations.”

The day we stop doing experimental or observational tests of our theories — the day we totally divorce science from testability — is the day we stop doing physics. Do you know where the word physics comes from? It’s from the ancient greek work, φύσις, which is best translated as “nature.” The study of physics is a study of the natural, physical world. Simulations are useful, particularly about the past, but are only really informative when you can compare the results of a simulation with something physically observable.

If you don’t deem it necessary to compare the existing Universe with what you predict or simulate, you are engaging in exercise for your imagination and for possibilities, but you are not doing physics. If you think there are no more doors to be opened, that’s fine; I don’t care if you give up. Just don’t expect many followers, particularly among physicists.

Artist's impression of a black hole. What goes on outside the black hole is well understood, but inside, we run up against the limits of fundamental physics... and potentially, the laws governing the Universe itself. Image credit: XMM-Newton, ESA, NASA.

Artist’s impression of a black hole. What goes on outside the black hole is well understood, but inside, we run up against the limits of fundamental physics… and potentially, the laws governing the Universe itself. Image credit: XMM-Newton, ESA, NASA.

From Andrew on event horizons in classical vs. quantum realities: “Remarkable, that event horizon, as it is described by GRT is far from what quantum theory says. When an observer falls to the black hole and crosses aforementioned event horizon, he notice nothing extraordinary (well, if the black hole is large enough). But, in accordance with quantum theory, there will be a firewall…”

So just to refresh your memory, because it’s been about four years since I wrote about it, here’s the deal with black holes, event horizons and firewalls:

  • Classically, the event horizon is the region within nothing, not even light, can escape.
  • Outside the event horizon, there is a location where you can have an innermost stable circular orbit (ISCO), where things outside of that orbit can exist stably but anything inside of it will spiral into the black hole.
  • In quantum physics, particles are entangled, meaning that two particles can have a property where the sum of the states is known, but an individual state of each is not determined until one or the other is measured.
  • If one entangled member of a pair falls into a black hole, and you measure the other one, you break the entanglement… but that causes a “firewall” of energetic particles to descend onto the black hole.

Given that particles fall into black holes and quantum entanglement is real, are firewalls real, and do you get fried falling in as a result? Probably not.

Image credit: Sabrina Herbst of Penn State.

Image credit: Sabrina Herbst of Penn State.

A 2013 paper showed that entanglement across all event horizons is maximized, which pushed the time of black hole firewall formation out to… infinity. Since black holes decay in a finite time, these firewalls shouldn’t exist in our Universe. It’s not that quantum physics is in conflict with classical physics, though; it’s that this is an effect that shows up only when you add quantum effects in to your background of classical spacetime.

We still have not figured out a quantum theory of spacetime, or of gravity, which some argue will be necessary to fully understand the firewall paradox, and other paradoxes about black holes.

The eight planets of our Solar System and our Sun, to scale in size but not in terms of orbital distances. Mercury is the most difficult naked-eye planet to see. Image credit: Wikimedia Commons user WP.

The eight planets of our Solar System and our Sun, to scale in size but not in terms of orbital distances. Mercury is the most difficult naked-eye planet to see. Image credit: Wikimedia Commons user WP.

From eric on an amusing fact about the 8 planets in our Solar System: “Amusing factoid: every planet in our solar system is more massive than all the planets smaller than it, combined. Thus, Venus has more mass than Mercury+Mars, Earth has more mass than Mercury+Mars+Venus, Uranus has more mass than Mercury+Mars+Venus+Earth, and so on.”

What’s also interesting is not just that this is true, but that it’s barely true! Venus (82% of Earth) plus Mars (11% of Earth) plus Mercury (5.5% of Earth) is almost equal to the mass of Earth, but not quite. Uranus (at 14.54 times the mass of Earth) plus all the rocky planets (1.98 Earth masses) comes out to 16.52 Earth masses, just shy of Neptune’s 17.15 Earth masses.

TRAPPIST-1 system compared to the solar system; all seven planets of TRAPPIST-1 could fit inside the orbit of Mercury. Note that at least the inner six worlds of TRAPPIST-1 are all locked to the star. Image credit: NASA / JPL-Caltech.

TRAPPIST-1 system compared to the solar system; all seven planets of TRAPPIST-1 could fit inside the orbit of Mercury. Note that at least the inner six worlds of TRAPPIST-1 are all locked to the star. Image credit: NASA / JPL-Caltech.

If you were to count Earth’s Moon and the four moons of Jupiter as “planets,” by the way — or go whole hog and buy into the “planetary science” definition of a planet — this fun fact would cease to be true. We know it is not a universal law, by the way, as many other solar systems, such as the TRAPPIST-1 system, violate this egregiously. In fact, if we consider that our Solar System likely once had a fifth rocky world similar in size to Mars that once collided with a proto-Earth, and that simulations indicate we once had a 5th gaseous world, it wasn’t always true for us, either.

Satellite photo of the Galapagos islands overlayed with the Spanish names of the visible main islands. The islands themselves are, at most, only a few million years old. Image credit: Jacques Descloitres, MODIS Rapid Response Project at NASA/GSFC.

Satellite photo of the Galapagos islands overlayed with the Spanish names of the visible main islands. The islands themselves are, at most, only a few million years old. Image credit: Jacques Descloitres, MODIS Rapid Response Project at NASA/GSFC.

From eric on Planet Earth II: “Watching Planet Earth II, I was struck by just how inhospitable Zavadovski Island is. Evidently the volcano is still active and has covered much of the island’s surface in fresh volcanic rock as recently as the 1800s. So basically, there’s little or no growing things on it. And yet, it’s home to a million penguins. So it’s not just mosses and algae that start the process of turning rocky wastelands into green pastures.”

Can I tell you how much I adore all of the BBC/Attenborough documentaries about nature and naturalism here on Earth? If you asked me to design my dream job — what I’d really like to do with my life if given the opportunity — it would be to do my own version of that for the Universe, astronomy and astrophysics. The Universe is out there, waiting for us to discover it, and the cosmic story is one we all share. I’d love to tell that story, as accurately and excitingly as possible, to anyone willing to listen and learn.

With all the active volcanic activity on the island, it's possible -- as the names suggest -- that Zavodovski island is also the smelliest place in the world. Image credit: UK Antarctic Place-names Committee / British Antarctic Survey / NERC.

With all the active volcanic activity on the island, it’s possible — as the names suggest — that Zavodovski island is also the smelliest place in the world. Image credit: UK Antarctic Place-names Committee / British Antarctic Survey / NERC.

Zavodovski Island, by the way, is not in the Galapagos, but is rather a 5 km by 5 km island located at the northern edge of the South Sandwich Islands in the southern Atlantic Ocean. It’s maybe 1,000 kilometers north of Antarctica, as the crow flies. And it was discovered two centuries ago, but two recent eruptions, in 2012 and 2016, have put the penguin colonies located there at risk. Remember, penguins go there for safety from predators, to breed, and to warm themselves in the Sun, not for food or shelter; they don’t exactly create green pastures on their own, but they are an important part of the ecosystem nonetheless.

Niels Bohr and Albert Einstein together in 1925, engaging in their famous conversations/debates about quantum mechanics. Public domain image.

Niels Bohr and Albert Einstein together in 1925, engaging in their famous conversations/debates about quantum mechanics. Public domain image.

From Denier on winning a scientific debate: “At the end of the day, more and better science will win. If you want to win a scientific debate then forget the debate and focus on doing more and better science.”

So what do you do when a scientific debate is over and won, and yet the policies and politics of the world refuses to accept the results? What would you do, hypothetically, in that case as it applies to a flat Earth, to relativity, to evolution, to the Big Bang, etc.? I bring up the Big Bang in contrast to the other three, because unlike a flat Earth (with implications for travel and commerce), relativity (technologies like GPS), evolution (health and medical breakthroughs), there is no tangible, physical, capitalistic benefit or consequence to “believing in” the Big Bang.

How would doing more and better science help the world win?

Image credit: Japan Meteorological Association (JMA), of the monthly average temperatures in February, going back as far as temperature records do. Via the Sydney Morning Herald at http://ift.tt/1LqCRlA.

Image credit: Japan Meteorological Association (JMA), of the monthly average temperatures in February, going back as far as temperature records do. Via the Sydney Morning Herald at http://ift.tt/1LqCRlA.

From Ragtag media exemplifying the difference between scientific and non-scientific debate: “OK my evidence is that a Steve Koonin was a Professor Of Theoretical Physics at Caltech, Was an Under Secretary of Science at the dept of Energy, and is the Director at NYU center for science and urban progress.
Says press releases put out by the govt was about climate data and climate analysis was “MISLEADING and sometimes just WRONG”
FACT,FACT,FACT”

How does one person’s credentials, employment history, and claims made by them without showing the supporting scientific evidence count as a valid part of a scientific debate? What is the data? What do you think the world’s temperature is doing? What do you think atmospheric gases are doing? What do you think is the connection between temperature and these gases, and what do you think is responsible for the changes in gas concentration?

Do you see the difference between scientific questions and politicized accusations, and does it matter to you? Or is your goal to find and amplify the voices of the people who agree with you to sow doubt and outrage among those doing more and better science to further verify and solidify an already robust conclusion?

Mongo McMichael vs. Jeff Jarrett, 1997, WCW.

Mongo McMichael vs. Jeff Jarrett, 1997, WCW.

From lloyd on commenter policies: “Regarding denier, CFT and ragtag media: can we have Wow back now please?”

Wow is welcome back, as he was after his temporary 1 week ban. If denier, CFT, Ragtag media or anyone else engage in outrageous personal attacks or affronts against other individuals here they will be banned as well. Affronts against reason, logic, or scientific facts are not given bans in the same way; unless someone else is promoting their own pet theories/websites/spam sources, I don’t ban for that.

The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA’s Aqua satellite senses temperature using infrared wavelengths. This image shows temperature of the Earth’s surface or clouds covering it for the month of April 2003. The scale ranges from -81 degrees Celsius (-114° Fahrenheit) in black/blue to 47° C (116° F) in red. Higher latitudes are increasingly obscured by clouds, though some features like the Great Lakes are apparent. Northernmost Europe and Eurasia are completely obscured by clouds, while Antarctica stands out cold and clear at the bottom of the image. Image credit: NASA AIRS.

The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA’s Aqua satellite senses temperature using infrared wavelengths. This image shows temperature of the Earth’s surface or clouds covering it for the month of April 2003. The scale ranges from -81 degrees Celsius (-114° Fahrenheit) in black/blue to 47° C (116° F) in red. Higher latitudes are increasingly obscured by clouds, though some features like the Great Lakes are apparent. Northernmost Europe and Eurasia are completely obscured by clouds, while Antarctica stands out cold and clear at the bottom of the image. Image credit: NASA AIRS.

From John on what science should be: “I think the purpose of Science is to describe – ideally to explain – the physical world. The purpose of Science is not to win debates. Science “wins” debates by providing a correct description or explanation of an event or process. Leave oratorical sleights of hand to others.”

I think that first sentence is definitely true; the second is arguably true; the third is demonstrably untrue as respects human beings on this planet. So… then what? Where are the “others” who will sway public opinion into agreement with the scientific conclusions? Will the real slim shady please stand up?

Cosmic rays produced by high-energy astrophysics sources can reach Earth's surface. By detecting these fast-moving particles correctly, we can put Einstein's relativity to the test. Image credit: ASPERA collaboration / AStroParticle ERAnet.

Cosmic rays produced by high-energy astrophysics sources can reach Earth’s surface. By detecting these fast-moving particles correctly, we can put Einstein’s relativity to the test. Image credit: ASPERA collaboration / AStroParticle ERAnet.

From D.C. Sessions on proving relativity for yourself: “$100? Spendthrift. Why not just run a current through a pair of wires and watch as they attract (or repel) each other. Special relativity at work, as even the slow drift velocity is enough to unbalance the effective balance between the forces exerted by moving electrons and stationary protons.”

And you are measuring the drift velocity of electrons how? And this is special relativity rather than electric current how? I am not saying that you are wrong; I am saying that this is not exactly a clear and obvious demonstration of relativity the way that receiving and observing a slew of unstable particles created very large distances away — that shouldn’t exist without relativity — are.

Image credit: Einstein deriving special relativity, 1934, via http://ift.tt/1AFefJn.

Image credit: Einstein deriving special relativity, 1934, via http://ift.tt/1AFefJn.

From Frank on proving Einstein wrong: “I had read somewhere that one time a reporter said to Einstein “There are hundred professors who say you are wrong.”
Einstein answered “If I was really wrong just one professor would be enough.””

This is very, very relevant. I will try and keep this in mind, and see if I can source that and verify its validity.

A quantum eraser experiment setup, where two entangled particles are separated and measured. No alterations of one particle at its destination affect the outcome of the other. Image credit: Wikimedia Commons user Patrick Edwin Moran, under c.c.a.-s.a.-3.0.

A quantum eraser experiment setup, where two entangled particles are separated and measured. No alterations of one particle at its destination affect the outcome of the other. Image credit: Wikimedia Commons user Patrick Edwin Moran, under c.c.a.-s.a.-3.0.

From Sinisa Lazarek quoting the Stanford Encyclopedia of Philosophy: ““11. Conclusion
Grammatical variants of the term ‘observation’ have been applied to impressively different perceptual and non-perceptual process and to records of the results they produce. Their diversity is a reason to doubt whether general philosophical accounts of observation, observables, and observational data can tell epistemologists as much as local accounts grounded in close studies of specific kinds of cases. Furthermore, scientists continue to find ways to produce data that can’t be called observational without stretching the term to the point of vagueness.
It’s plausible that philosophers who value the kind of rigor, precision, and generality to which l logical empiricists and other exact philosophers aspired could do better by examining and developing techniques and results from logic, probability theory, statistics, machine learning, and computer modeling, etc. than by trying to construct highly general theories of observation and its role in science. Logic and the rest seem unable to deliver satisfactory, universally applicable accounts of scientific reasoning. But they have illuminating local applications, some of which can be of use to scientists as well as philosophers.””

If you’re more concerned with an ideology or the “purity” of a definition than what’s actually scientifically robust about observations, prediction, measurement and reproducibility, that’s your prerogative, but please stay out of the way of those doing the science and adding to our actual, empirical understanding of the world. You are free to advocate for your preferred logical systems or syllogisms or definitions all you like, but don’t try and place unnecessary restrictions on physics; it won’t obey them anyway.

Image credit: John D. Norton, via http://ift.tt/1rCI50V.

Image credit: John D. Norton, via http://ift.tt/1rCI50V.

From Kasim Muflahi on misinterpreting relativity: “>>if you observe someone in motion relative to you, their clock will appear to run slow.
That’s because, as the clock moves further and further away from you, the images of the clock take longer and longer times to get to you giving the illusion that the clock is running slow.”

So I always hesitate to tell someone that they are wrong because I worry that they will not listen if they hear that… so let’s try a different approach.

Sure! When an object moves away from you, all the waves coming from it — including light waves — will take longer to reach you from crest-to-crest. So if your idea is correct, time should be sped-up as an object moves towards you, and it should remain constant when an object moves transverse to you.

Unfortunately, we can do the experiment, and not only is the clock really running slow (it’s not an illusion), but it does so independent of the redshift/blueshift of the waves. So we can put your idea to the test and show, scientifically, that it is not the way things actually work.

Thanks for a good week, everyone, and looking forward to another great week of science ahead!



from ScienceBlogs http://ift.tt/2qt7Q75

“Time travel used to be thought of as just science fiction, but Einstein’s general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out.” -Stephen Hawking

As always, there’s been a new fantastic week of articles here at Starts With A Bang, punctuated by our new podcast this month, on the physics of time travel!


Have a listen (or download it and take it with you) and thank our Patreon supporters for making it possible! Now, what was this past week all about? Come enjoy some fabulous stories if you missed anything, including:

There’s always so much more I could have talked about or so many more details I could have gone into but didn’t, and that’s what makes doing a follow-up so informative and educational. So let’s jump into what you wanted to learn or discuss more about here, and enjoy our comments of the week!

Image credit: Mark Garlick / SPL.

Image credit: Mark Garlick / SPL.

From Michael Mooney on his ‘key issues’ with relativity: “I am sorry that you refuse to address the core of the issue I bring to your forum.
Is there a “real world” independent of observation or not? (Yes, there is.)
Does the Earth physically change dimensions when (if ever) viewed from near light speed or not? (Ans: Not)
Does Earth’s atmosphere physically change in depth/height “for” every incoming muon or not? (Ans: Not.)”

When I “refuse to address” your issue it’s because you are asking a question that doesn’t have a scientific answer. I’m not in the business of giving you uninformed opinions and asserting them as facts. So if you want these three questions answered with scientific accuracy, let’s go.

1.) We cannot and have not ever measured the world independent of observation, and will never be able to do so. That is a fundamental limit of being a physical being in a physical Universe. Some things we can not observe for a very long time, then look at them and they will be exactly the same as a deterministic equation predicted. Others, if we observe them continuously, will give different results than if we didn’t look. So is there a “real world” independent of observation? You can’t answer, and I also assert that your quoted phrase “real world” is ambiguously defined.

Moving close to the speed of light results in times and distances transforming, with lengths -- including the length of your starship -- becoming shorter in the direction of motion. Image credit: David Taylor of Northwestern, via http://ift.tt/2m8aTPM.

Moving close to the speed of light results in times and distances transforming, with lengths — including the length of your starship — becoming shorter in the direction of motion. Image credit: David Taylor of Northwestern, via http://ift.tt/2m8aTPM.

2.) Does Earth physically change dimensions when viewed near the speed of light? The answer is yes, dependent on which observer you ask. If I ask you, on Earth, whether Earth’s physical dimensions change, the answer is no. If I ask the traveler whether they do, the answer is yes. There are some things that are invariant under relativistic transformations, but physical extents in space are not one of them.

Cosmic rays shower particles by striking protons and atoms in the atmosphere, but they also emit light due to Cherenkov radiation. Image credit: Simon Swordy (U. Chicago), NASA.

Cosmic rays shower particles by striking protons and atoms in the atmosphere, but they also emit light due to Cherenkov radiation. Image credit: Simon Swordy (U. Chicago), NASA.

3.) Does the Earth’s atmosphere change for every incoming relativistic particle? It’s not a “change,” as you incorrectly use the word, but it achieves a unique size/extent with respect to that particle, defined by that particle’s motion. The size of the atmosphere is entirely dependent on that particle’s frame-of-reference, and there is no definition of size/length/distance/spatial extent independent of reference frame in relativity.

Now, I have stated previously to you that there is an apparent length contraction that is not visually real, and I want you to understand why. If an object is moving close to the speed of light and it is emitting/reflecting photons, the way the object appears will often be uncontracted because of the superimposed effects of length contraction atop the fact that the speed of light is finite and not much greater than the moving object. You can also get visual effects that appear to move faster-than-light, known as photonic booms. But the thing you want to be invariant — the physical size of a physical object — simply isn’t, nor is it well-defined in the absence of an observer.

Image credit: CERN/Maximlien Brice, of the CMS detector, the small detector at the LHC.

Image credit: CERN/Maximlien Brice, of the CMS detector, the small detector at the LHC.

From Elle H.C. on the future of science: “‘Real’ physical testing isn’t going to open any new doors (physics). The future will come from fiddling and experimenting with computer simulations.”

The day we stop doing experimental or observational tests of our theories — the day we totally divorce science from testability — is the day we stop doing physics. Do you know where the word physics comes from? It’s from the ancient greek work, φύσις, which is best translated as “nature.” The study of physics is a study of the natural, physical world. Simulations are useful, particularly about the past, but are only really informative when you can compare the results of a simulation with something physically observable.

If you don’t deem it necessary to compare the existing Universe with what you predict or simulate, you are engaging in exercise for your imagination and for possibilities, but you are not doing physics. If you think there are no more doors to be opened, that’s fine; I don’t care if you give up. Just don’t expect many followers, particularly among physicists.

Artist's impression of a black hole. What goes on outside the black hole is well understood, but inside, we run up against the limits of fundamental physics... and potentially, the laws governing the Universe itself. Image credit: XMM-Newton, ESA, NASA.

Artist’s impression of a black hole. What goes on outside the black hole is well understood, but inside, we run up against the limits of fundamental physics… and potentially, the laws governing the Universe itself. Image credit: XMM-Newton, ESA, NASA.

From Andrew on event horizons in classical vs. quantum realities: “Remarkable, that event horizon, as it is described by GRT is far from what quantum theory says. When an observer falls to the black hole and crosses aforementioned event horizon, he notice nothing extraordinary (well, if the black hole is large enough). But, in accordance with quantum theory, there will be a firewall…”

So just to refresh your memory, because it’s been about four years since I wrote about it, here’s the deal with black holes, event horizons and firewalls:

  • Classically, the event horizon is the region within nothing, not even light, can escape.
  • Outside the event horizon, there is a location where you can have an innermost stable circular orbit (ISCO), where things outside of that orbit can exist stably but anything inside of it will spiral into the black hole.
  • In quantum physics, particles are entangled, meaning that two particles can have a property where the sum of the states is known, but an individual state of each is not determined until one or the other is measured.
  • If one entangled member of a pair falls into a black hole, and you measure the other one, you break the entanglement… but that causes a “firewall” of energetic particles to descend onto the black hole.

Given that particles fall into black holes and quantum entanglement is real, are firewalls real, and do you get fried falling in as a result? Probably not.

Image credit: Sabrina Herbst of Penn State.

Image credit: Sabrina Herbst of Penn State.

A 2013 paper showed that entanglement across all event horizons is maximized, which pushed the time of black hole firewall formation out to… infinity. Since black holes decay in a finite time, these firewalls shouldn’t exist in our Universe. It’s not that quantum physics is in conflict with classical physics, though; it’s that this is an effect that shows up only when you add quantum effects in to your background of classical spacetime.

We still have not figured out a quantum theory of spacetime, or of gravity, which some argue will be necessary to fully understand the firewall paradox, and other paradoxes about black holes.

The eight planets of our Solar System and our Sun, to scale in size but not in terms of orbital distances. Mercury is the most difficult naked-eye planet to see. Image credit: Wikimedia Commons user WP.

The eight planets of our Solar System and our Sun, to scale in size but not in terms of orbital distances. Mercury is the most difficult naked-eye planet to see. Image credit: Wikimedia Commons user WP.

From eric on an amusing fact about the 8 planets in our Solar System: “Amusing factoid: every planet in our solar system is more massive than all the planets smaller than it, combined. Thus, Venus has more mass than Mercury+Mars, Earth has more mass than Mercury+Mars+Venus, Uranus has more mass than Mercury+Mars+Venus+Earth, and so on.”

What’s also interesting is not just that this is true, but that it’s barely true! Venus (82% of Earth) plus Mars (11% of Earth) plus Mercury (5.5% of Earth) is almost equal to the mass of Earth, but not quite. Uranus (at 14.54 times the mass of Earth) plus all the rocky planets (1.98 Earth masses) comes out to 16.52 Earth masses, just shy of Neptune’s 17.15 Earth masses.

TRAPPIST-1 system compared to the solar system; all seven planets of TRAPPIST-1 could fit inside the orbit of Mercury. Note that at least the inner six worlds of TRAPPIST-1 are all locked to the star. Image credit: NASA / JPL-Caltech.

TRAPPIST-1 system compared to the solar system; all seven planets of TRAPPIST-1 could fit inside the orbit of Mercury. Note that at least the inner six worlds of TRAPPIST-1 are all locked to the star. Image credit: NASA / JPL-Caltech.

If you were to count Earth’s Moon and the four moons of Jupiter as “planets,” by the way — or go whole hog and buy into the “planetary science” definition of a planet — this fun fact would cease to be true. We know it is not a universal law, by the way, as many other solar systems, such as the TRAPPIST-1 system, violate this egregiously. In fact, if we consider that our Solar System likely once had a fifth rocky world similar in size to Mars that once collided with a proto-Earth, and that simulations indicate we once had a 5th gaseous world, it wasn’t always true for us, either.

Satellite photo of the Galapagos islands overlayed with the Spanish names of the visible main islands. The islands themselves are, at most, only a few million years old. Image credit: Jacques Descloitres, MODIS Rapid Response Project at NASA/GSFC.

Satellite photo of the Galapagos islands overlayed with the Spanish names of the visible main islands. The islands themselves are, at most, only a few million years old. Image credit: Jacques Descloitres, MODIS Rapid Response Project at NASA/GSFC.

From eric on Planet Earth II: “Watching Planet Earth II, I was struck by just how inhospitable Zavadovski Island is. Evidently the volcano is still active and has covered much of the island’s surface in fresh volcanic rock as recently as the 1800s. So basically, there’s little or no growing things on it. And yet, it’s home to a million penguins. So it’s not just mosses and algae that start the process of turning rocky wastelands into green pastures.”

Can I tell you how much I adore all of the BBC/Attenborough documentaries about nature and naturalism here on Earth? If you asked me to design my dream job — what I’d really like to do with my life if given the opportunity — it would be to do my own version of that for the Universe, astronomy and astrophysics. The Universe is out there, waiting for us to discover it, and the cosmic story is one we all share. I’d love to tell that story, as accurately and excitingly as possible, to anyone willing to listen and learn.

With all the active volcanic activity on the island, it's possible -- as the names suggest -- that Zavodovski island is also the smelliest place in the world. Image credit: UK Antarctic Place-names Committee / British Antarctic Survey / NERC.

With all the active volcanic activity on the island, it’s possible — as the names suggest — that Zavodovski island is also the smelliest place in the world. Image credit: UK Antarctic Place-names Committee / British Antarctic Survey / NERC.

Zavodovski Island, by the way, is not in the Galapagos, but is rather a 5 km by 5 km island located at the northern edge of the South Sandwich Islands in the southern Atlantic Ocean. It’s maybe 1,000 kilometers north of Antarctica, as the crow flies. And it was discovered two centuries ago, but two recent eruptions, in 2012 and 2016, have put the penguin colonies located there at risk. Remember, penguins go there for safety from predators, to breed, and to warm themselves in the Sun, not for food or shelter; they don’t exactly create green pastures on their own, but they are an important part of the ecosystem nonetheless.

Niels Bohr and Albert Einstein together in 1925, engaging in their famous conversations/debates about quantum mechanics. Public domain image.

Niels Bohr and Albert Einstein together in 1925, engaging in their famous conversations/debates about quantum mechanics. Public domain image.

From Denier on winning a scientific debate: “At the end of the day, more and better science will win. If you want to win a scientific debate then forget the debate and focus on doing more and better science.”

So what do you do when a scientific debate is over and won, and yet the policies and politics of the world refuses to accept the results? What would you do, hypothetically, in that case as it applies to a flat Earth, to relativity, to evolution, to the Big Bang, etc.? I bring up the Big Bang in contrast to the other three, because unlike a flat Earth (with implications for travel and commerce), relativity (technologies like GPS), evolution (health and medical breakthroughs), there is no tangible, physical, capitalistic benefit or consequence to “believing in” the Big Bang.

How would doing more and better science help the world win?

Image credit: Japan Meteorological Association (JMA), of the monthly average temperatures in February, going back as far as temperature records do. Via the Sydney Morning Herald at http://ift.tt/1LqCRlA.

Image credit: Japan Meteorological Association (JMA), of the monthly average temperatures in February, going back as far as temperature records do. Via the Sydney Morning Herald at http://ift.tt/1LqCRlA.

From Ragtag media exemplifying the difference between scientific and non-scientific debate: “OK my evidence is that a Steve Koonin was a Professor Of Theoretical Physics at Caltech, Was an Under Secretary of Science at the dept of Energy, and is the Director at NYU center for science and urban progress.
Says press releases put out by the govt was about climate data and climate analysis was “MISLEADING and sometimes just WRONG”
FACT,FACT,FACT”

How does one person’s credentials, employment history, and claims made by them without showing the supporting scientific evidence count as a valid part of a scientific debate? What is the data? What do you think the world’s temperature is doing? What do you think atmospheric gases are doing? What do you think is the connection between temperature and these gases, and what do you think is responsible for the changes in gas concentration?

Do you see the difference between scientific questions and politicized accusations, and does it matter to you? Or is your goal to find and amplify the voices of the people who agree with you to sow doubt and outrage among those doing more and better science to further verify and solidify an already robust conclusion?

Mongo McMichael vs. Jeff Jarrett, 1997, WCW.

Mongo McMichael vs. Jeff Jarrett, 1997, WCW.

From lloyd on commenter policies: “Regarding denier, CFT and ragtag media: can we have Wow back now please?”

Wow is welcome back, as he was after his temporary 1 week ban. If denier, CFT, Ragtag media or anyone else engage in outrageous personal attacks or affronts against other individuals here they will be banned as well. Affronts against reason, logic, or scientific facts are not given bans in the same way; unless someone else is promoting their own pet theories/websites/spam sources, I don’t ban for that.

The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA’s Aqua satellite senses temperature using infrared wavelengths. This image shows temperature of the Earth’s surface or clouds covering it for the month of April 2003. The scale ranges from -81 degrees Celsius (-114° Fahrenheit) in black/blue to 47° C (116° F) in red. Higher latitudes are increasingly obscured by clouds, though some features like the Great Lakes are apparent. Northernmost Europe and Eurasia are completely obscured by clouds, while Antarctica stands out cold and clear at the bottom of the image. Image credit: NASA AIRS.

The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA’s Aqua satellite senses temperature using infrared wavelengths. This image shows temperature of the Earth’s surface or clouds covering it for the month of April 2003. The scale ranges from -81 degrees Celsius (-114° Fahrenheit) in black/blue to 47° C (116° F) in red. Higher latitudes are increasingly obscured by clouds, though some features like the Great Lakes are apparent. Northernmost Europe and Eurasia are completely obscured by clouds, while Antarctica stands out cold and clear at the bottom of the image. Image credit: NASA AIRS.

From John on what science should be: “I think the purpose of Science is to describe – ideally to explain – the physical world. The purpose of Science is not to win debates. Science “wins” debates by providing a correct description or explanation of an event or process. Leave oratorical sleights of hand to others.”

I think that first sentence is definitely true; the second is arguably true; the third is demonstrably untrue as respects human beings on this planet. So… then what? Where are the “others” who will sway public opinion into agreement with the scientific conclusions? Will the real slim shady please stand up?

Cosmic rays produced by high-energy astrophysics sources can reach Earth's surface. By detecting these fast-moving particles correctly, we can put Einstein's relativity to the test. Image credit: ASPERA collaboration / AStroParticle ERAnet.

Cosmic rays produced by high-energy astrophysics sources can reach Earth’s surface. By detecting these fast-moving particles correctly, we can put Einstein’s relativity to the test. Image credit: ASPERA collaboration / AStroParticle ERAnet.

From D.C. Sessions on proving relativity for yourself: “$100? Spendthrift. Why not just run a current through a pair of wires and watch as they attract (or repel) each other. Special relativity at work, as even the slow drift velocity is enough to unbalance the effective balance between the forces exerted by moving electrons and stationary protons.”

And you are measuring the drift velocity of electrons how? And this is special relativity rather than electric current how? I am not saying that you are wrong; I am saying that this is not exactly a clear and obvious demonstration of relativity the way that receiving and observing a slew of unstable particles created very large distances away — that shouldn’t exist without relativity — are.

Image credit: Einstein deriving special relativity, 1934, via http://ift.tt/1AFefJn.

Image credit: Einstein deriving special relativity, 1934, via http://ift.tt/1AFefJn.

From Frank on proving Einstein wrong: “I had read somewhere that one time a reporter said to Einstein “There are hundred professors who say you are wrong.”
Einstein answered “If I was really wrong just one professor would be enough.””

This is very, very relevant. I will try and keep this in mind, and see if I can source that and verify its validity.

A quantum eraser experiment setup, where two entangled particles are separated and measured. No alterations of one particle at its destination affect the outcome of the other. Image credit: Wikimedia Commons user Patrick Edwin Moran, under c.c.a.-s.a.-3.0.

A quantum eraser experiment setup, where two entangled particles are separated and measured. No alterations of one particle at its destination affect the outcome of the other. Image credit: Wikimedia Commons user Patrick Edwin Moran, under c.c.a.-s.a.-3.0.

From Sinisa Lazarek quoting the Stanford Encyclopedia of Philosophy: ““11. Conclusion
Grammatical variants of the term ‘observation’ have been applied to impressively different perceptual and non-perceptual process and to records of the results they produce. Their diversity is a reason to doubt whether general philosophical accounts of observation, observables, and observational data can tell epistemologists as much as local accounts grounded in close studies of specific kinds of cases. Furthermore, scientists continue to find ways to produce data that can’t be called observational without stretching the term to the point of vagueness.
It’s plausible that philosophers who value the kind of rigor, precision, and generality to which l logical empiricists and other exact philosophers aspired could do better by examining and developing techniques and results from logic, probability theory, statistics, machine learning, and computer modeling, etc. than by trying to construct highly general theories of observation and its role in science. Logic and the rest seem unable to deliver satisfactory, universally applicable accounts of scientific reasoning. But they have illuminating local applications, some of which can be of use to scientists as well as philosophers.””

If you’re more concerned with an ideology or the “purity” of a definition than what’s actually scientifically robust about observations, prediction, measurement and reproducibility, that’s your prerogative, but please stay out of the way of those doing the science and adding to our actual, empirical understanding of the world. You are free to advocate for your preferred logical systems or syllogisms or definitions all you like, but don’t try and place unnecessary restrictions on physics; it won’t obey them anyway.

Image credit: John D. Norton, via http://ift.tt/1rCI50V.

Image credit: John D. Norton, via http://ift.tt/1rCI50V.

From Kasim Muflahi on misinterpreting relativity: “>>if you observe someone in motion relative to you, their clock will appear to run slow.
That’s because, as the clock moves further and further away from you, the images of the clock take longer and longer times to get to you giving the illusion that the clock is running slow.”

So I always hesitate to tell someone that they are wrong because I worry that they will not listen if they hear that… so let’s try a different approach.

Sure! When an object moves away from you, all the waves coming from it — including light waves — will take longer to reach you from crest-to-crest. So if your idea is correct, time should be sped-up as an object moves towards you, and it should remain constant when an object moves transverse to you.

Unfortunately, we can do the experiment, and not only is the clock really running slow (it’s not an illusion), but it does so independent of the redshift/blueshift of the waves. So we can put your idea to the test and show, scientifically, that it is not the way things actually work.

Thanks for a good week, everyone, and looking forward to another great week of science ahead!



from ScienceBlogs http://ift.tt/2qt7Q75

Why do we celebrate May Day?

Maypole wrapping in 2005 at Bryn Mawr College in Pennsylvania, where May Day festivities are an annual tradition. Image via Mike Goren via Wikimedia Commons

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You might not realize it, but May Day – an ancient spring festival in the Northern Hemisphere – is an astronomical holiday. It’s one of the year’s four cross-quarter days, or a day that falls more or less midway between an equinox and solstice, in this case the March equinox and June solstice. The other cross-quarter days are Groundhog Day on February 2, Lammas on August 1 and Halloween on October 31. May Day also stems from the Celtic festival of Beltane, which was related to the waxing power of the sun as we in the Northern Hemisphere move closer to summer. At Beltane, people lit fires through which livestock were driven and around which people danced, moving in the same direction that the sun crosses the sky.

School children rehearsing Maypole festivity, in Gee's Bend, Alabama, 1939. Image via Wikimedia Commons

The top of a Maypole set up for a May 1 celebration. Image via WrldVoyagr/Flickr.

A group of happy neighbors in Texas in 2012, after wrapping a Maypole. See the wrapped pole being held up? Image via Rick Patrick

Wrapping a Maypole with colorful ribbons is perhaps the best known of all May Day traditions. In the Middle Ages, English villages all had Maypoles, which were actual trees brought in from the woods in the midst of rejoicing and raucous merrymaking. Maypoles came in many sizes, and villages were said to compete with each other to show whose Maypole was tallest. Maypoles were usually set up for the day in small towns, but in London and the larger towns they were erected permanently.

We’re not too far away from a time in the late 20th century when people left homemade May baskets filled with spring flowers and sweets on each others’ doorsteps, usually anonymously. I can remember doing this as a child. Maybe it’s a tradition that can be revived.

Homemade May basket left on neighbor or friend's doorstep anonymously. Nice tradition!

Bottom line: May 1 is one of four cross-quarter days, midway between an equinox and a solstice. It stems from the ancient festival of Beltane, which relates to the waxing power of the sun at this time of year. Wrapping a Maypole is its most recognized tradition.



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Maypole wrapping in 2005 at Bryn Mawr College in Pennsylvania, where May Day festivities are an annual tradition. Image via Mike Goren via Wikimedia Commons

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You might not realize it, but May Day – an ancient spring festival in the Northern Hemisphere – is an astronomical holiday. It’s one of the year’s four cross-quarter days, or a day that falls more or less midway between an equinox and solstice, in this case the March equinox and June solstice. The other cross-quarter days are Groundhog Day on February 2, Lammas on August 1 and Halloween on October 31. May Day also stems from the Celtic festival of Beltane, which was related to the waxing power of the sun as we in the Northern Hemisphere move closer to summer. At Beltane, people lit fires through which livestock were driven and around which people danced, moving in the same direction that the sun crosses the sky.

School children rehearsing Maypole festivity, in Gee's Bend, Alabama, 1939. Image via Wikimedia Commons

The top of a Maypole set up for a May 1 celebration. Image via WrldVoyagr/Flickr.

A group of happy neighbors in Texas in 2012, after wrapping a Maypole. See the wrapped pole being held up? Image via Rick Patrick

Wrapping a Maypole with colorful ribbons is perhaps the best known of all May Day traditions. In the Middle Ages, English villages all had Maypoles, which were actual trees brought in from the woods in the midst of rejoicing and raucous merrymaking. Maypoles came in many sizes, and villages were said to compete with each other to show whose Maypole was tallest. Maypoles were usually set up for the day in small towns, but in London and the larger towns they were erected permanently.

We’re not too far away from a time in the late 20th century when people left homemade May baskets filled with spring flowers and sweets on each others’ doorsteps, usually anonymously. I can remember doing this as a child. Maybe it’s a tradition that can be revived.

Homemade May basket left on neighbor or friend's doorstep anonymously. Nice tradition!

Bottom line: May 1 is one of four cross-quarter days, midway between an equinox and a solstice. It stems from the ancient festival of Beltane, which relates to the waxing power of the sun at this time of year. Wrapping a Maypole is its most recognized tradition.



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Are we alarmed yet? [Greg Laden's Blog]

Climate science deniers like to call we who are correct and rational (we the good guys) “alarmists.” So be it.

This is a post that closely reflects my own feelings, by my friend and colleague, Lawrence Torcello. It begins:

Most of us have wondered about the human context of past crimes against humanity: why didn’t more people intervene? How could so many pretend not to know? To be sure, crimes against humanity are not always easy to identify while they unfold.

We need some time to reflect and to analyze, even when our reasoning suggests that large scale human suffering and death are likely imminent. The principled condemnation of large scale atrocity is, too often

GO HERE AND READ IT



from ScienceBlogs http://ift.tt/2oVjEh5

Climate science deniers like to call we who are correct and rational (we the good guys) “alarmists.” So be it.

This is a post that closely reflects my own feelings, by my friend and colleague, Lawrence Torcello. It begins:

Most of us have wondered about the human context of past crimes against humanity: why didn’t more people intervene? How could so many pretend not to know? To be sure, crimes against humanity are not always easy to identify while they unfold.

We need some time to reflect and to analyze, even when our reasoning suggests that large scale human suffering and death are likely imminent. The principled condemnation of large scale atrocity is, too often

GO HERE AND READ IT



from ScienceBlogs http://ift.tt/2oVjEh5

Simulating the smallest ring world

The Center for Computational Astrophysics in New York said on Friday (April 28, 2017) that Japanese researchers have modeled the two known rings around 10199 Chariklo, a possible dwarf planet orbiting the sun between the major planets Saturn and Uranus. They say it’s the first time an entire ring system has been simulated using realistic sizes for the ring particles while also taking into account collisions and gravitational interactions between the particles. They also created the visuals on this page, including the video above, which lets you dive into Chariklo’s ring system. Note that Chariklo itself is really potato-shaped and no doubt pocked with craters; the round, smooth shape in the video is for purposes of the simulation.

These researchers’ work is published in the peer-reviewed March 2017 edition of The Astrophysical Journal Letters.

Chariklo is a tiny world. Its estimated size about 200 miles (334 km) by about 140 miles (226 km) by about 100 miles (172 km). Our solar system’s major outer planets (Jupiter, Saturn, Uranus, Neptune) all are known to have rings. These planets’ rings are composed of particles estimated to range from inches to several feet (centimeters to meters) in size. Chariklo’s gravitational attraction is small relative to the major planets, so its rings – which were discovered in 2014 – are likely only temporary.

Although Chariklo is small, and although its gravity is relatively weak, its rings are as opaque as those around Saturn and Uranus. Thus, the researchers said, Chariklo offered an ideal chance to model a complete ring system.

The team said their simulation revealed information about the size and density of the particles in the rings. They found that Chariklo’s inner ring should be unstable without help. So – the researchers said – the ring particles must be much smaller than previously thought. Or it means that an undiscovered shepherd satellite around Chariklo is stabilizing the ring.

Visualization constructed from simulation of Chariklo’s double ring. Note that Chariklo itself is really potato-shaped and no doubt pocked with craters; the round, smooth shape here is for purposes of the simulation. Image via Shugo Michikoshi, Eiichiro Kokubo, Hirotaka Nakayama, 4D2U Project, NAOJ/ CFCA.

The researchers – Shugo Michikoshi (Kyoto Women’s University/University of Tsukuba) and Eiichiro Kokubo (National Astronomical Observatory of Japan, or NAOJ) modeled Chariklo’s rings using the supercomputer ATERUI*1 at NAOJ. They calculated the motions of 345 million ring particles with the realistic size of a few meters taking into account the collisions and mutual gravitational attractions between the particles.

Chariklo is the largest member of a class known as the Centaurs, orbiting between Saturn and Uranus in the outer solar system. These bodies are categorized like asteroids, but, whereas most asteroids lie in the asteroid belt between Mars and Jupiter – closer to the sun – Centaurs may have come from the Kuiper Belt, which is visualized as extending from the orbit of the outermost major planet Neptune to approximately 50 Earth-sun units (AU) from our sun. Centaurs have unstable orbits that cross the giant planets’ orbit. Chariklo’s orbit gazes that of Uranus. Because their orbits are frequently perturbed, Centaurs like Chariklo are expected to only remain in their orbits only for millions of years, in contrast to our Earth and the other major planets which have been orbiting for billions of years around our sun.

The new computer visualization suggests that the density of Chariklo’s ring particles must be less than half the density of Chariklo itself. And they show a striped pattern forming in the inner ring due to interactions between the particles. They use the term “self-gravity wakes” for this pattern (see the image below). These self-gravity wakes accelerate the break-up of the ring, the researchers said.

But perhaps the most surprising result of the new study is a recalculated life expectancy for Chariklo’s rings. The study suggests the rings may be able to reamin around Chariklo for only one to 100 years! That’s much shorter than previous estimates, and it’s less than an eye-blink in astronomical terms.

So what we are seeing with Chariklo and its ring system is likely a very temporary and dynamic situation. Things in space tend to happen on a vastly-longer timescales than we humans are used to, but sometimes things do happen on human timescales. Chariklo’s rings may be an example!

Simulation of Chariklo’s ring system. The researchers said they used a ring particle density equal to half of Chariklo’s density, in order to maintain the rings’ overall structure. In the close-up view (right) complicated, elongated structures are visible. These structures are called self-gravity wakes. The numbers along the axes indicate distances in km. Image via Shugo Michikoshi / CFCA.

Bottom line: Chariklo – a possible dwarf planet orbiting between Saturn and Uranus – has been known to have rings since 2014. Japanese researchers have created a first-ever supercomputer simulation of Chariklo’s surprising rings.



from EarthSky http://ift.tt/2qsbxtq

The Center for Computational Astrophysics in New York said on Friday (April 28, 2017) that Japanese researchers have modeled the two known rings around 10199 Chariklo, a possible dwarf planet orbiting the sun between the major planets Saturn and Uranus. They say it’s the first time an entire ring system has been simulated using realistic sizes for the ring particles while also taking into account collisions and gravitational interactions between the particles. They also created the visuals on this page, including the video above, which lets you dive into Chariklo’s ring system. Note that Chariklo itself is really potato-shaped and no doubt pocked with craters; the round, smooth shape in the video is for purposes of the simulation.

These researchers’ work is published in the peer-reviewed March 2017 edition of The Astrophysical Journal Letters.

Chariklo is a tiny world. Its estimated size about 200 miles (334 km) by about 140 miles (226 km) by about 100 miles (172 km). Our solar system’s major outer planets (Jupiter, Saturn, Uranus, Neptune) all are known to have rings. These planets’ rings are composed of particles estimated to range from inches to several feet (centimeters to meters) in size. Chariklo’s gravitational attraction is small relative to the major planets, so its rings – which were discovered in 2014 – are likely only temporary.

Although Chariklo is small, and although its gravity is relatively weak, its rings are as opaque as those around Saturn and Uranus. Thus, the researchers said, Chariklo offered an ideal chance to model a complete ring system.

The team said their simulation revealed information about the size and density of the particles in the rings. They found that Chariklo’s inner ring should be unstable without help. So – the researchers said – the ring particles must be much smaller than previously thought. Or it means that an undiscovered shepherd satellite around Chariklo is stabilizing the ring.

Visualization constructed from simulation of Chariklo’s double ring. Note that Chariklo itself is really potato-shaped and no doubt pocked with craters; the round, smooth shape here is for purposes of the simulation. Image via Shugo Michikoshi, Eiichiro Kokubo, Hirotaka Nakayama, 4D2U Project, NAOJ/ CFCA.

The researchers – Shugo Michikoshi (Kyoto Women’s University/University of Tsukuba) and Eiichiro Kokubo (National Astronomical Observatory of Japan, or NAOJ) modeled Chariklo’s rings using the supercomputer ATERUI*1 at NAOJ. They calculated the motions of 345 million ring particles with the realistic size of a few meters taking into account the collisions and mutual gravitational attractions between the particles.

Chariklo is the largest member of a class known as the Centaurs, orbiting between Saturn and Uranus in the outer solar system. These bodies are categorized like asteroids, but, whereas most asteroids lie in the asteroid belt between Mars and Jupiter – closer to the sun – Centaurs may have come from the Kuiper Belt, which is visualized as extending from the orbit of the outermost major planet Neptune to approximately 50 Earth-sun units (AU) from our sun. Centaurs have unstable orbits that cross the giant planets’ orbit. Chariklo’s orbit gazes that of Uranus. Because their orbits are frequently perturbed, Centaurs like Chariklo are expected to only remain in their orbits only for millions of years, in contrast to our Earth and the other major planets which have been orbiting for billions of years around our sun.

The new computer visualization suggests that the density of Chariklo’s ring particles must be less than half the density of Chariklo itself. And they show a striped pattern forming in the inner ring due to interactions between the particles. They use the term “self-gravity wakes” for this pattern (see the image below). These self-gravity wakes accelerate the break-up of the ring, the researchers said.

But perhaps the most surprising result of the new study is a recalculated life expectancy for Chariklo’s rings. The study suggests the rings may be able to reamin around Chariklo for only one to 100 years! That’s much shorter than previous estimates, and it’s less than an eye-blink in astronomical terms.

So what we are seeing with Chariklo and its ring system is likely a very temporary and dynamic situation. Things in space tend to happen on a vastly-longer timescales than we humans are used to, but sometimes things do happen on human timescales. Chariklo’s rings may be an example!

Simulation of Chariklo’s ring system. The researchers said they used a ring particle density equal to half of Chariklo’s density, in order to maintain the rings’ overall structure. In the close-up view (right) complicated, elongated structures are visible. These structures are called self-gravity wakes. The numbers along the axes indicate distances in km. Image via Shugo Michikoshi / CFCA.

Bottom line: Chariklo – a possible dwarf planet orbiting between Saturn and Uranus – has been known to have rings since 2014. Japanese researchers have created a first-ever supercomputer simulation of Chariklo’s surprising rings.



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