Joy in Mudville

by Tom Damm

Photo: Courtesy of Jim Bintliff

If you were lucky enough to catch one of the record number of home run balls hit in Major League ballparks this year, you may have noticed that the ball didn’t look brand new – that there was some sort of film over it.  Mud to be exact.

All baseballs used in the professional leagues are rubbed up before games with mud found only at a secret location along a tributary of the Delaware River.  It’s been that way for decades.

After a batter was killed with an errant pitch in 1920, the search was on for a substance to give a fresh baseball a better grip without altering its integrity.  Chewing tobacco juice and infield dirt mixed with water were among the remedies tried to no avail.  In 1938, Lena Blackburne, a coach for the old Philadelphia Athletics, found mud with just the right composition at a spot off the New Jersey side of the river.  And it’s been used ever since.

What makes this mud so special?

“It’s two very simple things,” says Jim Bintliff, who has continued the family mud supply operation his grandfather started with Blackburne.  “It’s the geology and the geography.  The mineral content of the area is unique and there has to be a certain flow to the waterway that allows for sediment and decomposition (of the organic matter) and all that good stuff.”

As to claims by some pitchers that this year’s World Series balls seem slicker than usual, Bintliff says, “They’re using the same mud they used during the (regular) season.” Bintliff supplied the Dodgers and Astros and the rest of the teams with their mud allotments in March.

Bintliff says that in addition to all the pro baseball teams, he provides mud to “probably half of the NFL teams,” as well as to a posh Philadelphia spa and an assortment of college and recreational leagues.  He also uses it as a home remedy for poison ivy and bee stings.

According to Bintliff, the skimmed mud is strained of foreign objects and then cured for about six weeks.  A proprietary ingredient is added to the mix to give it the right feel.  The texture of the finished product is like thick pudding.

The rubbing mud is an unusual, though representative example of the “ecosystem services” provided by the Delaware Basin.  The basin is a focus of cleanup and preservation efforts by two EPA regions, four states and a host of other partners.

So, while the Phillies team didn’t make the playoffs this year, the Philadelphia area was represented in the post-season by a touch of the Delaware on the cover of every baseball.  Little solace to fans, but a handy bit of trivia.

 

About the Author: Tom Damm has been with EPA since 2002 and now serves as communications coordinator for the region’s Water Protection Division.

from The EPA Blog http://ift.tt/2gQWHtL

by Tom Damm

Photo: Courtesy of Jim Bintliff

If you were lucky enough to catch one of the record number of home run balls hit in Major League ballparks this year, you may have noticed that the ball didn’t look brand new – that there was some sort of film over it.  Mud to be exact.

All baseballs used in the professional leagues are rubbed up before games with mud found only at a secret location along a tributary of the Delaware River.  It’s been that way for decades.

After a batter was killed with an errant pitch in 1920, the search was on for a substance to give a fresh baseball a better grip without altering its integrity.  Chewing tobacco juice and infield dirt mixed with water were among the remedies tried to no avail.  In 1938, Lena Blackburne, a coach for the old Philadelphia Athletics, found mud with just the right composition at a spot off the New Jersey side of the river.  And it’s been used ever since.

What makes this mud so special?

“It’s two very simple things,” says Jim Bintliff, who has continued the family mud supply operation his grandfather started with Blackburne.  “It’s the geology and the geography.  The mineral content of the area is unique and there has to be a certain flow to the waterway that allows for sediment and decomposition (of the organic matter) and all that good stuff.”

As to claims by some pitchers that this year’s World Series balls seem slicker than usual, Bintliff says, “They’re using the same mud they used during the (regular) season.” Bintliff supplied the Dodgers and Astros and the rest of the teams with their mud allotments in March.

Bintliff says that in addition to all the pro baseball teams, he provides mud to “probably half of the NFL teams,” as well as to a posh Philadelphia spa and an assortment of college and recreational leagues.  He also uses it as a home remedy for poison ivy and bee stings.

According to Bintliff, the skimmed mud is strained of foreign objects and then cured for about six weeks.  A proprietary ingredient is added to the mix to give it the right feel.  The texture of the finished product is like thick pudding.

The rubbing mud is an unusual, though representative example of the “ecosystem services” provided by the Delaware Basin.  The basin is a focus of cleanup and preservation efforts by two EPA regions, four states and a host of other partners.

So, while the Phillies team didn’t make the playoffs this year, the Philadelphia area was represented in the post-season by a touch of the Delaware on the cover of every baseball.  Little solace to fans, but a handy bit of trivia.

 

About the Author: Tom Damm has been with EPA since 2002 and now serves as communications coordinator for the region’s Water Protection Division.

from The EPA Blog http://ift.tt/2gQWHtL

$2 million NSF grant funds physicists' quest for optical transistors

"The ultimate goal is making it possible to devise all-optical computers and telecommunications," says Hayk Harutyunyan, left, with Ajit Srivastava. 

By Carol Clark

The National Science Foundation awarded two Emory physicists a $2 million Emergent Frontiers grant, for development of miniaturized optical transistors to take computers and telecommunications into a new era.

“We are working to change some properties of light — such as making it travel in only one direction — by using atomically thin, two-dimensional materials,” says Ajit Srivastava, assistant professor of physics and principal investigator for the grant. “These novel materials are being touted as the next silicon. They could open the door to even smaller and more efficient electronics than are possible today.”

Srivastava’s co-investigators include Hayk Harutyunyan, also an assistant professor of physics at Emory, as well as scientists from Georgia State and Stanford universities.

“The ultimate goal is making it possible to devise all-optical computers and telecommunications,” Harutyunyan says.

A major revolution in telecommunications occurred in the 1950s, driven by the development of silicon semiconductors as miniature transistors to control the flow of electrical current. These transistors led to smaller, faster computers and paved the way for everything from flatscreen TVs to cell phones.

“They changed civilization,” Harutyunyan says. “Every year new computers would come out with faster processors as the transistors got tinier and more efficient. But about a decade ago this progress stopped, because these transistors cannot be made any smaller than about 15 nanometers and still function well.”

Meanwhile, the gradual replacement of copper wiring with fiber optics is speeding up transmissions between computers and other electronic devices and allowing for greater bandwidth. “When you send an email from Atlanta to Europe, the information is encoded into light and relayed by fiber optic cables running under the ocean,” Srivastava explains. “It’s super fast, because light is the fastest thing that you can imagine.”

Unlike in our everyday life, however, where the arrow of time moves in one direction, light photos operate at the quantum scale and can move back and forth. This lack of a fixed direction is called reciprocity. “Reciprocity in optics,” Srivastava says, “can best be described by a familiar observation: ‘If I can see you, you can see me.’”

Fiber optic cables use magnetic fields to break reciprocity and prevent light from reflecting off surfaces and creating “noise” in a signal. The required magnetic devices, known as optical isolators, are typically bulky and heavy because tiny magnets are not strong enough to do the job.

The Emory project aims to develop powerful nonreciprocal optical devices that are not based on magnets and can function at the nanoscale.

Srivastava’s lab is investigating the potential of transition metal dichalcogenides, or TMDs. TMDs are semiconductors within a new family of two-dimensional, extraordinarily thin materials. While the smallest feature of a current computer processor is 14 nanometers thick, a TMD monolayer is smaller than a single nanometer.

Harutyunyan’s lab, meanwhile, is exploring ways to make interactions between light and matter stronger through the use of metallic nano particles. Metals are shiny because of their free electrons that easily interact with light. The oscillations of these free electrons, called plasmons, allow metallic nano-particles to funnel large amounts of light into tiny dimensions.

A long-term goal of the project is to hybridize TMDs and metallic particles into nanomaterials that use laser fields to create the same light-guiding effects of magnetic fields. Such devices have the potential to be faster and cheaper and offer more precise control of the light-directing process. They would also be much smaller than existing optical isolators and transistors.

“Nano-science is an exciting area,” Srivastava says. “You can imagine the possibility of flexible cell phones or even wearable electronic membranes that would take the shape of your body.”

More powerful computers could also ramp up the ability of scientists to analyze massive datasets faster, Harutyunyan notes.

The Emory grant will also fund public outreach projects in Atlanta area schools. “We want people to understand the importance of fundamental science research,” Harutyunyan says. “And we want to inspire young people to think about science careers.

from eScienceCommons http://ift.tt/2hqppT5

"The ultimate goal is making it possible to devise all-optical computers and telecommunications," says Hayk Harutyunyan, left, with Ajit Srivastava. 

By Carol Clark

The National Science Foundation awarded two Emory physicists a $2 million Emergent Frontiers grant, for development of miniaturized optical transistors to take computers and telecommunications into a new era.

“We are working to change some properties of light — such as making it travel in only one direction — by using atomically thin, two-dimensional materials,” says Ajit Srivastava, assistant professor of physics and principal investigator for the grant. “These novel materials are being touted as the next silicon. They could open the door to even smaller and more efficient electronics than are possible today.”

Srivastava’s co-investigators include Hayk Harutyunyan, also an assistant professor of physics at Emory, as well as scientists from Georgia State and Stanford universities.

“The ultimate goal is making it possible to devise all-optical computers and telecommunications,” Harutyunyan says.

A major revolution in telecommunications occurred in the 1950s, driven by the development of silicon semiconductors as miniature transistors to control the flow of electrical current. These transistors led to smaller, faster computers and paved the way for everything from flatscreen TVs to cell phones.

“They changed civilization,” Harutyunyan says. “Every year new computers would come out with faster processors as the transistors got tinier and more efficient. But about a decade ago this progress stopped, because these transistors cannot be made any smaller than about 15 nanometers and still function well.”

Meanwhile, the gradual replacement of copper wiring with fiber optics is speeding up transmissions between computers and other electronic devices and allowing for greater bandwidth. “When you send an email from Atlanta to Europe, the information is encoded into light and relayed by fiber optic cables running under the ocean,” Srivastava explains. “It’s super fast, because light is the fastest thing that you can imagine.”

Unlike in our everyday life, however, where the arrow of time moves in one direction, light photos operate at the quantum scale and can move back and forth. This lack of a fixed direction is called reciprocity. “Reciprocity in optics,” Srivastava says, “can best be described by a familiar observation: ‘If I can see you, you can see me.’”

Fiber optic cables use magnetic fields to break reciprocity and prevent light from reflecting off surfaces and creating “noise” in a signal. The required magnetic devices, known as optical isolators, are typically bulky and heavy because tiny magnets are not strong enough to do the job.

The Emory project aims to develop powerful nonreciprocal optical devices that are not based on magnets and can function at the nanoscale.

Srivastava’s lab is investigating the potential of transition metal dichalcogenides, or TMDs. TMDs are semiconductors within a new family of two-dimensional, extraordinarily thin materials. While the smallest feature of a current computer processor is 14 nanometers thick, a TMD monolayer is smaller than a single nanometer.

Harutyunyan’s lab, meanwhile, is exploring ways to make interactions between light and matter stronger through the use of metallic nano particles. Metals are shiny because of their free electrons that easily interact with light. The oscillations of these free electrons, called plasmons, allow metallic nano-particles to funnel large amounts of light into tiny dimensions.

A long-term goal of the project is to hybridize TMDs and metallic particles into nanomaterials that use laser fields to create the same light-guiding effects of magnetic fields. Such devices have the potential to be faster and cheaper and offer more precise control of the light-directing process. They would also be much smaller than existing optical isolators and transistors.

“Nano-science is an exciting area,” Srivastava says. “You can imagine the possibility of flexible cell phones or even wearable electronic membranes that would take the shape of your body.”

More powerful computers could also ramp up the ability of scientists to analyze massive datasets faster, Harutyunyan notes.

The Emory grant will also fund public outreach projects in Atlanta area schools. “We want people to understand the importance of fundamental science research,” Harutyunyan says. “And we want to inspire young people to think about science careers.

from eScienceCommons http://ift.tt/2hqppT5

New data gives hope for meeting the Paris climate targets

Over the past half-century, growth in the global economy and carbon pollution have been tied together. When the global economy has been strong, we’ve consumed more energy, which has translated into burning more fossil fuels and releasing more carbon pollution. But over the past four years, economic growth and carbon dioxide emissions have been decoupled. The global economy has continued to grow, while data from the EU Joint Research Centre shows carbon pollution has held fairly steady.

Annual global carbon dioxide and gross domestic product growth. Data from the EU Joint Research Centre and World Bank. Illustration: Dana Nuccitelli

China is becoming a global climate leader

China’s shift away from coal to clean energy has been largely responsible for this decoupling. Due to its large population (1.4 billion) – more than four times that of the USA (323 million) and nearly triple the EU (510 million) – and rapid growth in its economy and coal power supply, China has become the world’s largest net carbon polluter (though still less than half America’s per-person carbon emissions, and on par with those of Europeans). But as with the global total, China’s carbon pollution has flattened out since 2013.

 

That’s especially remarkable because it puts China about 15 years ahead of schedule. In an agreement with President Obama ahead of the Paris international climate negotiations, Chinese President Xi Jingping pledged that China’s carbon emissions would peak by 2030. Republican Party leaders grossly distorted this agreement at the time, with Senate majority leader Mitch McConnell claiming:

As I read the agreement it requires the Chinese to do nothing at all for 16 years while these carbon emissions regulations are creating havoc in my state and around the country

As the chart above shows, Chinese carbon emissions tripled between 1999 and 2013. To slow that rate of growth to zero as the Chinese economy continues to grow would require a dramatic shift in the country’s energy supply. But that’s exactly what’s happened, with the Chinese government cancelling over 100 planned new coal power plants earlier this year. Chinese coal consumption has in fact fallen since 2013. And China and the EU have pledged to strengthen their efforts to cut carbon pollution.

America isn’t a lost cause

In 2016, American carbon pollution fell to below 1993 levels. The emissions decline began around 2008, which is also when natural gas, solar, and wind energy began rapidly replacing coal in the power grid.

The Trump administration has done everything in its power to reverse that trend. It began the withdrawal from the Paris climate agreement and the process to repeal the Clean Power Plan, has begun censoring EPA climate scientists and deleting climate change information from government websites, and proposed to prop up the dirty, failing coal industry with taxpayer-funded subsidies.

And yet, while these steps can slow the decline in American carbon pollution, the transition from coal to clean energy will nevertheless persist. Coal simply can no longer compete with cheaper, cleaner sources of energy, and the next American president can quickly reverse many of the Trump administration’s anti-climate orders.

Click here to read the rest

from Skeptical Science http://ift.tt/2ijE6qT

Over the past half-century, growth in the global economy and carbon pollution have been tied together. When the global economy has been strong, we’ve consumed more energy, which has translated into burning more fossil fuels and releasing more carbon pollution. But over the past four years, economic growth and carbon dioxide emissions have been decoupled. The global economy has continued to grow, while data from the EU Joint Research Centre shows carbon pollution has held fairly steady.

Annual global carbon dioxide and gross domestic product growth. Data from the EU Joint Research Centre and World Bank. Illustration: Dana Nuccitelli

China is becoming a global climate leader

China’s shift away from coal to clean energy has been largely responsible for this decoupling. Due to its large population (1.4 billion) – more than four times that of the USA (323 million) and nearly triple the EU (510 million) – and rapid growth in its economy and coal power supply, China has become the world’s largest net carbon polluter (though still less than half America’s per-person carbon emissions, and on par with those of Europeans). But as with the global total, China’s carbon pollution has flattened out since 2013.

 

That’s especially remarkable because it puts China about 15 years ahead of schedule. In an agreement with President Obama ahead of the Paris international climate negotiations, Chinese President Xi Jingping pledged that China’s carbon emissions would peak by 2030. Republican Party leaders grossly distorted this agreement at the time, with Senate majority leader Mitch McConnell claiming:

As I read the agreement it requires the Chinese to do nothing at all for 16 years while these carbon emissions regulations are creating havoc in my state and around the country

As the chart above shows, Chinese carbon emissions tripled between 1999 and 2013. To slow that rate of growth to zero as the Chinese economy continues to grow would require a dramatic shift in the country’s energy supply. But that’s exactly what’s happened, with the Chinese government cancelling over 100 planned new coal power plants earlier this year. Chinese coal consumption has in fact fallen since 2013. And China and the EU have pledged to strengthen their efforts to cut carbon pollution.

America isn’t a lost cause

In 2016, American carbon pollution fell to below 1993 levels. The emissions decline began around 2008, which is also when natural gas, solar, and wind energy began rapidly replacing coal in the power grid.

The Trump administration has done everything in its power to reverse that trend. It began the withdrawal from the Paris climate agreement and the process to repeal the Clean Power Plan, has begun censoring EPA climate scientists and deleting climate change information from government websites, and proposed to prop up the dirty, failing coal industry with taxpayer-funded subsidies.

And yet, while these steps can slow the decline in American carbon pollution, the transition from coal to clean energy will nevertheless persist. Coal simply can no longer compete with cheaper, cleaner sources of energy, and the next American president can quickly reverse many of the Trump administration’s anti-climate orders.

Click here to read the rest

from Skeptical Science http://ift.tt/2ijE6qT

November guide to the bright planets

Venus – the brightest planet – has a conjunction with Spica, the brightest star in the constellation Virgo, in late October and early November 2017. They are closest on the morning of November 2. Read more.

Two of the five bright planets – Saturn and Mercury – are evening planets, but only Saturn is clearly visible after nightfall in early November, 2017. Mercury is lost in the sunset glare during the first half of the month and will likely be seen after mid-month. The other three bright planets – dazzlingly bright Venus, extremely bright Jupiter and super-faint Mars – adorn the morning sky, before sunup. Venus and Jupiter will have a spectacular conjunction – albeit low in the sky – around November 13. Follow the links below to learn more about the planets in November 2017.

Venus, brilliant in east at morning dawn

Jupiter climbs out of the glare of sunrise

Mars visible in eastern predawn sky

Saturn out from dusk until early evening

Seek for Mercury after sunset

EarthSky’s 2018 lunar calendars are here! Get yours while they last.

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Astronomy events, star parties, festivals, workshops

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

Don’t miss the Venus/Jupiter conjunction on or around November 13, 2017. Read more.

And wow! Just as Venus and Jupiter are closest, the moon will be there, too. Let the moon be your guide to the early morning planets on November 13, 14, 15 and 16. Read more.

Venus, brilliant in east at morning dawn Venus is always brilliant and beautiful, the brightest celestial body to light up our sky besides the sun and moon. Although it’s lower in the sky now than it was a month ago, if you’re an early bird, you can count on Venus to be your morning companion throughout November, 2017.

Although Venus will remain in the morning sky for the rest of this year, this dazzling planet will sink closer and closer to the glare of sunrise over the next two months.

As Venus sinks downward in our morning sky (really, moving behind the sun as seen from our earthly perspective), Jupiter will be climbing upward, out of the dawn.

Watch for Venus and Jupiter to have a spectacular conjunction in the morning sky on or around November 13. Around that same time, enjoy the picturesque displays of the waning crescent moon with Venus, Jupiter and Mars. the moon and Venus will be closest on the mornings of November 16 and November 17.

Jenney Disimon in Sabah, Borneo captured Venus before dawn. It’s easy to spot, the brightest object in our sky besides the sun and moon.

Venus reached a milestone as the morning “star” when it swung out to its greatest elongation from the sun on June 3, 2017. At this juncture, Venus was farthest from the sun on our sky’s dome, and a telescope showed Venus as half-illuminated in sunshine, like a first quarter moon. For the rest of the year, Venus will wax toward full phase.

Click here to know Venus’s exact phase at present, remembering to select Venus as your object of interest.

From mid-northern latitudes (U.S. and Europe), Venus rises about one and one-half before the sun in early November, and about 45 minutes before sunrise by the month’s end.

At temperate latitudes in the Southern Hemisphere (Australia and South Africa), Venus rises about 40 minutes before sunup in early November. By the month’s end, that’ll taper to about 30 minutes.

Click here for recommended almanacs; they can provide rising times of Venus in your sky.

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

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 chart is so special that we’re using it twice in this post! Don’t miss the Venus/Jupiter conjunction on or around November 13, 2017. Read more.

Jupiter climbs out of the glare of sunrise. Jupiter’s very recent conjunction with the sun – when it was traveling more or less behind the sun from Earth – happened on October 26, 2017. That event marked Jupiter’s official transition out of the evening sky and into the morning sky. Look for the king planet to creep back into the morning sky – appearing as a strangely bright object low on the sunrise horizon – after the first week of November, 2017.

By around mid-month, a wonderful event will occur! Jupiter will join up with Venus to stage a close conjunction in the eastern morning sky on November 13. It’ll be amazing to see Venus, the sky’s brightest planet, and Jupiter, the second-brightest planet, presenting their closest conjunction since August 27, 2016!

What’s more, the moon will join the show. Let the waning crescent moon guide your eye to Jupiter (and Venus) on or before the mornings of November 16 and November 17.

After the conjunction of Venus and Jupiter on November 13, look for Venus to sink into the glare of sunrise and for Jupiter to climb away from the twilight glare. For the rest of this year, Jupiter will close the gap between itself and the red planet Mars, which appears higher up in the November morning sky. Jupiter will meet up with Mars, to stage a stunningly close conjunction in the morning sky on January 7, 2018.

From mid-northern latitudes, Jupiter rises about one-half hour before the sun in early November. By late November, Jupiter will rise about two hours before sunrise.

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

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).

Jupiter starts the month of November, 2017 in front of the constellation Virgo, fairly close to Virgo’s sole 1st-magnitude star, called Spica.

By mid-month, Jupiter will enter into the constellation Libra.

If you have binoculars or a telescope, it’s fairly easy to see Jupiter’s four major moons, which look like pinpricks of light all 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 orbit Jupiter around the Jovian equator. In cycles of six years, we view Jupiter’s equator edge-on. So, in 2015, we were able to view a number of mutual events involving Jupiter’s moons, through high-powered telescopes. Starting in late 2016, Jupiter’s axis began tilting enough toward the sun and Earth so that the farthest of these four moons, Callisto, has not been passing in front of Jupiter or behind Jupiter, as seen from our vantage point. This will continue for a period of about three years, during which time Callisto is perpetually visible to those with telescopes, alternately swinging above and below Jupiter as seen from Earth.

Click here for a Jupiter’s moons almanac, courtesy of skyandtelescope.com.

Mars, Mercury, Earth’s moon and the dwarf planet Ceres. Mars is smaller than Earth, but bigger than our moon. Image via NASA/JPL-Caltech/UCLA.

Let the waning crescent moon guide your eye to the planet Mars on the mornings of November 14 and 15. Read more.

Mars visible in eastern predawn sky. Mars transitioned out of the evening sky and into the morning sky on July 27, 2017, at which juncture Mars was on the far side of the sun at what astronomers call superior conjunction.

Look for Mars to rise in the east before dawn’s first light. Mars is the only one of the three morning planets – Venus, Mars and Jupiter – to grace the predawn sky throughout the month. Jupiter begins the month deeply buried in the glow of twilight whereas Venus ends the month deeply buried in the twilight glare.

It’s best to look for Mars before dawn (approximately one and one-half hours before sunrise) because this second-magnitude gem is only modestly bright right now. Mars is nowhere as brilliant as Venus or Jupiter, which are easily visible in a twilight sky.

Be sure to let the waning crescent moon help guide your eye to Mars on the mornings of November 14 and 15.

Exactly one year after Mars’s superior conjunction on July 27, 2017, Mars will swing to opposition on July 27, 2018. This will be Mars’s best opposition since its historically close opposition on August 28, 2003. In fact, Mars will become the fourth-brightest heavenly body to light up the sky in July 2018, after the sun, moon and the planet Venus. It’s not often that Mars outshines Jupiter, normally the fourth-brightest celestial object.

James Martin in Albuquerque, New Mexico caught this wonderful photo of Saturn on its June 15, 2017 opposition.

Let the moon help guide your eye to the planet Saturn (and possibly Mercury) for several days, centered on or near November 20. Read more.

Saturn out from dusk until early evening. On these November evenings, look for Saturn as soon as darkness falls. It’s in the southwest sky at dusk or nightfall. Your best view of Saturn, from either the Northern or Southern Hemisphere, is around nightfall because that’s when Saturn is highest up for the night.

From mid-northern latitudes (US and Europe), Saturn sets about one hour after nightfall in early November and around nightfall (1.5 hours after sunset) by the month’s end.

From temperate latitudes in the Southern Hemisphere (South Africa, southern Australia), Saturn sets about 2 hours after nightfall in early November and around nightfall by the month’s end.

From anywhere worldwide, this will be the final full month for seeing Saturn in the evening sky before it transitions over into the morning sky in December 2017.

Be sure to let the moon guide you to Saturn (and possibly Mercury, which lurks beneath Saturn) for several days, centered on or near November 20. Saturn and Mercury will be in conjunction on November 28.

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 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 now inclined at nearly 27^o from edge-on, exhibiting their northern face. In 2017, the north side of the rings opened up most widely since since the last grand opening in 1988. The next maximum exposure of the north side of Saturn’s rings will take place in 2046.

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 27^o by May 2032.

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

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

Let the moon help guide your eye to the planet Mercury on November 19, 20 and 21. Read more.

Seek for Mercury after sunset. This apparition of Mercury in the November evening sky greatly favors the Southern Hemisphere. Even so, we at mid-northern latitudes have a fairly decent shot of catching this world in the second half of the month.

Mercury is tricky, even when it becomes visible. If you look too early, Mercury will still be obscured by evening twilight; if you look too late, it will have followed the sun beneath the horizon. Watch for Mercury low in the sky, and near the sunset point on the horizon, being mindful of Mercury’s setting time.

Let the thin waxing crescent moon help guide your eye to Mercury, the solar system’s innermost planet, on the evenings of November 19, 20 and 21. Then watch for the conjunction of Mercury and Saturn on November 28.

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.

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.

Bottom line: In November 2017, two of the five bright planets – Saturn and Mercury – reign as evening planets, and the other three bright planets – Venus, Mars and Jupiter – are found in the morning sky, before sunup.

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Venus – the brightest planet – has a conjunction with Spica, the brightest star in the constellation Virgo, in late October and early November 2017. They are closest on the morning of November 2. Read more.

Two of the five bright planets – Saturn and Mercury – are evening planets, but only Saturn is clearly visible after nightfall in early November, 2017. Mercury is lost in the sunset glare during the first half of the month and will likely be seen after mid-month. The other three bright planets – dazzlingly bright Venus, extremely bright Jupiter and super-faint Mars – adorn the morning sky, before sunup. Venus and Jupiter will have a spectacular conjunction – albeit low in the sky – around November 13. Follow the links below to learn more about the planets in November 2017.

Venus, brilliant in east at morning dawn

Jupiter climbs out of the glare of sunrise

Mars visible in eastern predawn sky

Saturn out from dusk until early evening

Seek for Mercury after sunset

EarthSky’s 2018 lunar calendars are here! Get yours while they last.

Like what EarthSky offers? Sign up for our free daily newsletter today!

Astronomy events, star parties, festivals, workshops

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

Don’t miss the Venus/Jupiter conjunction on or around November 13, 2017. Read more.

And wow! Just as Venus and Jupiter are closest, the moon will be there, too. Let the moon be your guide to the early morning planets on November 13, 14, 15 and 16. Read more.

Venus, brilliant in east at morning dawn Venus is always brilliant and beautiful, the brightest celestial body to light up our sky besides the sun and moon. Although it’s lower in the sky now than it was a month ago, if you’re an early bird, you can count on Venus to be your morning companion throughout November, 2017.

Although Venus will remain in the morning sky for the rest of this year, this dazzling planet will sink closer and closer to the glare of sunrise over the next two months.

As Venus sinks downward in our morning sky (really, moving behind the sun as seen from our earthly perspective), Jupiter will be climbing upward, out of the dawn.

Watch for Venus and Jupiter to have a spectacular conjunction in the morning sky on or around November 13. Around that same time, enjoy the picturesque displays of the waning crescent moon with Venus, Jupiter and Mars. the moon and Venus will be closest on the mornings of November 16 and November 17.

Jenney Disimon in Sabah, Borneo captured Venus before dawn. It’s easy to spot, the brightest object in our sky besides the sun and moon.

Venus reached a milestone as the morning “star” when it swung out to its greatest elongation from the sun on June 3, 2017. At this juncture, Venus was farthest from the sun on our sky’s dome, and a telescope showed Venus as half-illuminated in sunshine, like a first quarter moon. For the rest of the year, Venus will wax toward full phase.

Click here to know Venus’s exact phase at present, remembering to select Venus as your object of interest.

From mid-northern latitudes (U.S. and Europe), Venus rises about one and one-half before the sun in early November, and about 45 minutes before sunrise by the month’s end.

At temperate latitudes in the Southern Hemisphere (Australia and South Africa), Venus rises about 40 minutes before sunup in early November. By the month’s end, that’ll taper to about 30 minutes.

Click here for recommended almanacs; they can provide rising times of Venus in your sky.

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

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 chart is so special that we’re using it twice in this post! Don’t miss the Venus/Jupiter conjunction on or around November 13, 2017. Read more.

Jupiter climbs out of the glare of sunrise. Jupiter’s very recent conjunction with the sun – when it was traveling more or less behind the sun from Earth – happened on October 26, 2017. That event marked Jupiter’s official transition out of the evening sky and into the morning sky. Look for the king planet to creep back into the morning sky – appearing as a strangely bright object low on the sunrise horizon – after the first week of November, 2017.

By around mid-month, a wonderful event will occur! Jupiter will join up with Venus to stage a close conjunction in the eastern morning sky on November 13. It’ll be amazing to see Venus, the sky’s brightest planet, and Jupiter, the second-brightest planet, presenting their closest conjunction since August 27, 2016!

What’s more, the moon will join the show. Let the waning crescent moon guide your eye to Jupiter (and Venus) on or before the mornings of November 16 and November 17.

After the conjunction of Venus and Jupiter on November 13, look for Venus to sink into the glare of sunrise and for Jupiter to climb away from the twilight glare. For the rest of this year, Jupiter will close the gap between itself and the red planet Mars, which appears higher up in the November morning sky. Jupiter will meet up with Mars, to stage a stunningly close conjunction in the morning sky on January 7, 2018.

From mid-northern latitudes, Jupiter rises about one-half hour before the sun in early November. By late November, Jupiter will rise about two hours before sunrise.

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

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).

Jupiter starts the month of November, 2017 in front of the constellation Virgo, fairly close to Virgo’s sole 1st-magnitude star, called Spica.

By mid-month, Jupiter will enter into the constellation Libra.

If you have binoculars or a telescope, it’s fairly easy to see Jupiter’s four major moons, which look like pinpricks of light all 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 orbit Jupiter around the Jovian equator. In cycles of six years, we view Jupiter’s equator edge-on. So, in 2015, we were able to view a number of mutual events involving Jupiter’s moons, through high-powered telescopes. Starting in late 2016, Jupiter’s axis began tilting enough toward the sun and Earth so that the farthest of these four moons, Callisto, has not been passing in front of Jupiter or behind Jupiter, as seen from our vantage point. This will continue for a period of about three years, during which time Callisto is perpetually visible to those with telescopes, alternately swinging above and below Jupiter as seen from Earth.

Click here for a Jupiter’s moons almanac, courtesy of skyandtelescope.com.

Mars, Mercury, Earth’s moon and the dwarf planet Ceres. Mars is smaller than Earth, but bigger than our moon. Image via NASA/JPL-Caltech/UCLA.

Let the waning crescent moon guide your eye to the planet Mars on the mornings of November 14 and 15. Read more.

Mars visible in eastern predawn sky. Mars transitioned out of the evening sky and into the morning sky on July 27, 2017, at which juncture Mars was on the far side of the sun at what astronomers call superior conjunction.

Look for Mars to rise in the east before dawn’s first light. Mars is the only one of the three morning planets – Venus, Mars and Jupiter – to grace the predawn sky throughout the month. Jupiter begins the month deeply buried in the glow of twilight whereas Venus ends the month deeply buried in the twilight glare.

It’s best to look for Mars before dawn (approximately one and one-half hours before sunrise) because this second-magnitude gem is only modestly bright right now. Mars is nowhere as brilliant as Venus or Jupiter, which are easily visible in a twilight sky.

Be sure to let the waning crescent moon help guide your eye to Mars on the mornings of November 14 and 15.

Exactly one year after Mars’s superior conjunction on July 27, 2017, Mars will swing to opposition on July 27, 2018. This will be Mars’s best opposition since its historically close opposition on August 28, 2003. In fact, Mars will become the fourth-brightest heavenly body to light up the sky in July 2018, after the sun, moon and the planet Venus. It’s not often that Mars outshines Jupiter, normally the fourth-brightest celestial object.

James Martin in Albuquerque, New Mexico caught this wonderful photo of Saturn on its June 15, 2017 opposition.

Let the moon help guide your eye to the planet Saturn (and possibly Mercury) for several days, centered on or near November 20. Read more.

Saturn out from dusk until early evening. On these November evenings, look for Saturn as soon as darkness falls. It’s in the southwest sky at dusk or nightfall. Your best view of Saturn, from either the Northern or Southern Hemisphere, is around nightfall because that’s when Saturn is highest up for the night.

From mid-northern latitudes (US and Europe), Saturn sets about one hour after nightfall in early November and around nightfall (1.5 hours after sunset) by the month’s end.

From temperate latitudes in the Southern Hemisphere (South Africa, southern Australia), Saturn sets about 2 hours after nightfall in early November and around nightfall by the month’s end.

From anywhere worldwide, this will be the final full month for seeing Saturn in the evening sky before it transitions over into the morning sky in December 2017.

Be sure to let the moon guide you to Saturn (and possibly Mercury, which lurks beneath Saturn) for several days, centered on or near November 20. Saturn and Mercury will be in conjunction on November 28.

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 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 now inclined at nearly 27^o from edge-on, exhibiting their northern face. In 2017, the north side of the rings opened up most widely since since the last grand opening in 1988. The next maximum exposure of the north side of Saturn’s rings will take place in 2046.

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 27^o by May 2032.

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

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

Let the moon help guide your eye to the planet Mercury on November 19, 20 and 21. Read more.

Seek for Mercury after sunset. This apparition of Mercury in the November evening sky greatly favors the Southern Hemisphere. Even so, we at mid-northern latitudes have a fairly decent shot of catching this world in the second half of the month.

Mercury is tricky, even when it becomes visible. If you look too early, Mercury will still be obscured by evening twilight; if you look too late, it will have followed the sun beneath the horizon. Watch for Mercury low in the sky, and near the sunset point on the horizon, being mindful of Mercury’s setting time.

Let the thin waxing crescent moon help guide your eye to Mercury, the solar system’s innermost planet, on the evenings of November 19, 20 and 21. Then watch for the conjunction of Mercury and Saturn on November 28.

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.

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.

Bottom line: In November 2017, two of the five bright planets – Saturn and Mercury – reign as evening planets, and the other three bright planets – Venus, Mars and Jupiter – are found in the morning sky, before sunup.

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Air Force Uses Cutting Edge 3-D Printing to Focus on Warfighter

Air Force innovation helps warfighters look ahead and build parts that would otherwise be obsolete.

from http://ift.tt/2zlel4k

Air Force innovation helps warfighters look ahead and build parts that would otherwise be obsolete.

from http://ift.tt/2zlel4k

Boo! Halloween star trails

Gowrishankar Lakshminarayanan, who composed this photo, calls it Keep Looking Up With Cosm-‘0’-Lanterns.

Gowrishankar Lakshminarayanan was at North South Lake Campground, Haines Falls, New York when he created this image of Halloween-themed star trails. He wrote:

I always wanted to do some kind of astro nightscapes with the Halloween ghosts/ghouls … That night was particularly cold with the onset of fall weather, and I had to battle strong winds that made the weather even more cold. Am happy none of my pumpkins got knocked off due to these heavy winds … had to secure them with tapes and back support. :)

In the background you can also see my another camera setup on a tracker … and, in the far back, one of my friend observing through his ‘scope.

Thanks, Gowri, and Happy Halloween to you!

Read more: How to take great photos of star trails

from EarthSky http://ift.tt/2hrP65C

Gowrishankar Lakshminarayanan, who composed this photo, calls it Keep Looking Up With Cosm-‘0’-Lanterns.

Gowrishankar Lakshminarayanan was at North South Lake Campground, Haines Falls, New York when he created this image of Halloween-themed star trails. He wrote:

I always wanted to do some kind of astro nightscapes with the Halloween ghosts/ghouls … That night was particularly cold with the onset of fall weather, and I had to battle strong winds that made the weather even more cold. Am happy none of my pumpkins got knocked off due to these heavy winds … had to secure them with tapes and back support. :)

In the background you can also see my another camera setup on a tracker … and, in the far back, one of my friend observing through his ‘scope.

Thanks, Gowri, and Happy Halloween to you!

Read more: How to take great photos of star trails

from EarthSky http://ift.tt/2hrP65C

Halloween is a cross-quarter day

Photo via Kurt Magoon/Flickr

2018 EarthSky lunar calendars are here! Get yours now.

Halloween – short for All Hallows’ Eve – is an astronomical holiday. Sure, it’s the modern-day descendant from Samhain, a sacred festival of the ancient Celts and Druids in the British Isles. But it’s also a cross-quarter day, which is probably why Samhain occurred when it did. Early people were keen observers of the sky. A cross-quarter day is a day more or less midway between an equinox (when the sun sets due west) and a solstice (when the sun sets at its most northern or southern point on the horizon). Halloween – October 31 – is approximately midway point between the autumn equinox and winter solstice, for us in the Northern Hemisphere.

In other words, in traditional astronomy, there are eight major seasonal subdivisions of every year. They include the March and September equinoxes, the June and December solstices, and the intervening four cross-quarter days.

In modern times, the four cross-quarter days are often called Groundhog Day (February 2), May Day (May 1), Lammas (August 1) and Halloween (October 31).

Equinoxes, solstices and cross-quarter days are all hallmarks of Earth’s orbit around the sun. Halloween is the 4th cross-quarter day of the year. Illustration via NASA

For us in the Northern Hemisphere, Halloween is the darkest of the cross-quarter days, coming at a time of year when the days are growing shorter. Early people once said that the spirits of the dead wander from sunset until midnight around this cross-quarter day. After midnight – on November 1, which we now call All Saints’ Day – the ghosts are said to go back to rest.

The October 31 date for Halloween has been fixed by tradition. The true cross-quarter day falls on November 7, representing a discrepancy of about a week. According to the ancient Celts, a cross-quarter day marks the beginning – not the middle – of a season.

The Pleiades star cluster, also known as the Seven Sisters. This tiny, misty dipper is easy to pick out in the night sky. Photo via Dave Dehetre/Flickr.

The Pleiades connection. It’s thought that the early forbearer of Halloween – Samhain – happened on the night that the Pleiades star cluster culminated at midnight.

In other words, the Pleiades climbed to its highest point in the sky at midnight on or near the same date as this cross-quarter day. In our day, Halloween is fixed on October 31, though the midnight culmination of the Pleiades cluster now occurs on November 21.

Presuming the supposed connection between Samhain and the midnight culmination of the Pleiades, the two events took place on or near the same date in the 11th century (1001-1100) and 12th century (1101-1200). This was several centuries before the introduction of the Gregorian calendar.

At that time, when the Julian calendar was in use, the cross-quarter day and the midnight culmination of the Pleiades fell – amazingly enough – on or near October 31. But, then, the Julian calendar was about one week out of step with the seasons. Had the Gregorian calendar been in use back then, the date of the cross-quarter day celebration would have been November 7.

Calendar converter

But Halloween is now fixed on October 31. Meanwhile, the true cross-quarter day now falls on or near November 7 and the midnight culmination of the Pleiades cluster on or near November 21.

Bottom line: The present date for Halloween – October 31 – marks the approximate midway point between the autumn equinox and the winter solstice. Halloween is one of the year’s four cross-quarter days.

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Photo via Kurt Magoon/Flickr

2018 EarthSky lunar calendars are here! Get yours now.

Halloween – short for All Hallows’ Eve – is an astronomical holiday. Sure, it’s the modern-day descendant from Samhain, a sacred festival of the ancient Celts and Druids in the British Isles. But it’s also a cross-quarter day, which is probably why Samhain occurred when it did. Early people were keen observers of the sky. A cross-quarter day is a day more or less midway between an equinox (when the sun sets due west) and a solstice (when the sun sets at its most northern or southern point on the horizon). Halloween – October 31 – is approximately midway point between the autumn equinox and winter solstice, for us in the Northern Hemisphere.

In other words, in traditional astronomy, there are eight major seasonal subdivisions of every year. They include the March and September equinoxes, the June and December solstices, and the intervening four cross-quarter days.

In modern times, the four cross-quarter days are often called Groundhog Day (February 2), May Day (May 1), Lammas (August 1) and Halloween (October 31).

Equinoxes, solstices and cross-quarter days are all hallmarks of Earth’s orbit around the sun. Halloween is the 4th cross-quarter day of the year. Illustration via NASA

For us in the Northern Hemisphere, Halloween is the darkest of the cross-quarter days, coming at a time of year when the days are growing shorter. Early people once said that the spirits of the dead wander from sunset until midnight around this cross-quarter day. After midnight – on November 1, which we now call All Saints’ Day – the ghosts are said to go back to rest.

The October 31 date for Halloween has been fixed by tradition. The true cross-quarter day falls on November 7, representing a discrepancy of about a week. According to the ancient Celts, a cross-quarter day marks the beginning – not the middle – of a season.

The Pleiades star cluster, also known as the Seven Sisters. This tiny, misty dipper is easy to pick out in the night sky. Photo via Dave Dehetre/Flickr.

The Pleiades connection. It’s thought that the early forbearer of Halloween – Samhain – happened on the night that the Pleiades star cluster culminated at midnight.

In other words, the Pleiades climbed to its highest point in the sky at midnight on or near the same date as this cross-quarter day. In our day, Halloween is fixed on October 31, though the midnight culmination of the Pleiades cluster now occurs on November 21.

Presuming the supposed connection between Samhain and the midnight culmination of the Pleiades, the two events took place on or near the same date in the 11th century (1001-1100) and 12th century (1101-1200). This was several centuries before the introduction of the Gregorian calendar.

At that time, when the Julian calendar was in use, the cross-quarter day and the midnight culmination of the Pleiades fell – amazingly enough – on or near October 31. But, then, the Julian calendar was about one week out of step with the seasons. Had the Gregorian calendar been in use back then, the date of the cross-quarter day celebration would have been November 7.

Calendar converter

But Halloween is now fixed on October 31. Meanwhile, the true cross-quarter day now falls on or near November 7 and the midnight culmination of the Pleiades cluster on or near November 21.

Bottom line: The present date for Halloween – October 31 – marks the approximate midway point between the autumn equinox and the winter solstice. Halloween is one of the year’s four cross-quarter days.

Enjoying EarthSky? Sign up for our free daily newsletter today!

from EarthSky http://ift.tt/1wKJ9jq

Deep-sea nightmares and other ocean spookiness

The Monterey Bay Aquarium Research Institute (MBARI) posted this video on its Facebook page this weekend and wrote:

To get you in the mood for Halloween, we bring you Deep-sea Nightmares!

Starring the black sea devil (Melanocetus), a skeleton shrimp (caprellid amphipod), the vampire squid (Vampyroteuthis infernalis), a bat-faced crab (Macroregonia macrochira), the fangtooth (Anoplogaster cornuta), a giant sea spider (as big as your open fist; not an actual spider, but an arthropod called a pycnogonid), bacterial ooze (growing on a hay bale placed at 3,000 m for a carbon experiment), the witch eel (Nettastomidae), a slimy mob of hagfish feeding on a dead fish, and the bloody-belly comb jelly (Lampocteis cruentiventer).

For more Halloween-themed videos from Monterey Bay Aquarium, check out this playlist on YouTube.

Video still via MBARI.

Bottom line: from Deep-Sea Nightmares video via Monterey Bay Aquarium Research Institute.

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

The Monterey Bay Aquarium Research Institute (MBARI) posted this video on its Facebook page this weekend and wrote:

To get you in the mood for Halloween, we bring you Deep-sea Nightmares!

Starring the black sea devil (Melanocetus), a skeleton shrimp (caprellid amphipod), the vampire squid (Vampyroteuthis infernalis), a bat-faced crab (Macroregonia macrochira), the fangtooth (Anoplogaster cornuta), a giant sea spider (as big as your open fist; not an actual spider, but an arthropod called a pycnogonid), bacterial ooze (growing on a hay bale placed at 3,000 m for a carbon experiment), the witch eel (Nettastomidae), a slimy mob of hagfish feeding on a dead fish, and the bloody-belly comb jelly (Lampocteis cruentiventer).

For more Halloween-themed videos from Monterey Bay Aquarium, check out this playlist on YouTube.

Video still via MBARI.

Bottom line: from Deep-Sea Nightmares video via Monterey Bay Aquarium Research Institute.

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

From cancer evolution to targeting faulty genetics – our new fellows

It’s time to welcome a new batch of researchers to the Cancer Research UK team. Here are some common themes they are researching, and how their work could help cancer patients in the future.

Targeting the faulty genetics of cancer

Dr Serena Nik-Zainal is exploring patterns of faults in DNA from cancer cells called signatures. This will help her understand how DNA is damaged inside cells, and how it’s repaired to help cells survive, which can lead to cancer.

Meanwhile, Dr Andrew Beggs, Dr Ross Carruthers, Dr Laureano de la Vega, and Dr Luca Magnani, are looking at the genetic changes that can help tumours become resistant to treatment.

Beggs is using mini lab-grown tumours called organoids to search for new drug targets to stop bowel cancer becoming resistant to treatment. Carruthers is exploring how brain tumours become resistant to radiotherapy. He’s trying to work out how cells from the most aggressive type of brain tumour, glioblastoma, are able to repair their DNA following radiotherapy and keep growing.

Transcription is a process that takes information from genes in our DNA to make proteins. de la Vega is looking at one molecule that controls transcription and has been thought of as protective against cancer. But recent research suggests in some situations it may actually help cancer cells become resistant to chemotherapy – de la Vega is investigating how this happens. Finally, Magnani is looking at way in which some mutations in the tumours are able to turn their genes ‘on’ or ‘off’ to escape treatments and spread around the body, focussing on breast cancer.

Corrupting healthy cells

Many different types of cell live alongside cancer cells and inside tumours as they grow. Dr Ahsan Akram and Professor Tim Underwood are looking at cells called cancer associated fibroblasts, which can help tumours grow and spread.

While Akram is developing a new way to see these cells in lung cancer to help doctors to decide what treatment to give patients, Underwood is trying to understand how oesophageal cancer cells hijack neighbouring healthy cells, and how the genetic changes in the cancer cells help them to do this. Dr Chris Tape is also interested in how the genetic changes in cancer cells help them to corrupt the healthy fibroblast cells and immune cells, focussing on bowel cancer.

Watch how cancer-associated fibroblasts help breast cancer cells spread

An immune attack

Recently, the immune system has emerged as a potentially powerful ally in tackling certain cancers. Dr Sheeba Irshad is investigating how immune cells move within tumours in the lab. By understanding the signals involved, she hopes to find a way to encourage particular immune cells to move into the tumour and kill the cancer cells.

Dr Tobias Janowitz is also investigating new ways to help the immune system tackle pancreatic cancer. He focuses on how tumours change the way that the body uses energy, which can lead to a wasting condition called cachexia. He wants to understand how this hinders the immune response to cancer, which allows the tumour to grow unchecked. By understanding more about these processes in the lab, he hopes to find a way to break this cycle and help tackle pancreatic cancer.

It’s in the blood

Blood stem cells must produce a constant supply of essential blood cells throughout a person’s lifetime, but when their DNA is damaged it can lead to blood cancers.

Dr Meng Wang is investigating how stem cell DNA can be damaged and fixed, which could point to the steps leading to cancer. Meanwhile, Dr Melinda Czeh is looking at how these stem cells change as people get older to try and understand how age increases the risk of acute myeloid leukaemia (AML).

Dr Beth Payne is also looking at what happens as people age in relation to AML, having seen some common genetic faults in older people. She wants to understand how these changes can lead to cancer, which could help identify new potential drug targets.

Evolution of cancer

Cancers cells can be cunning, changing as they evolve and become resistant to treatment. Dr Jyoti Nangalia and Dr Andrea Sottoriva are each taking a different approach to studying this evolution, in the hope of finding new ways to stop cancer in its tracks.

Nangalia is looking for genes that are important in a cancer’s evolution. She wants to predict which patients may be at a higher risk of their disease evolving, giving doctors a head start in planning treatment. Sottoriva is trying to map cancer evolution by taking a mathematical and computational approach. He also wants to anticipate which drugs would be best to give as the disease changes, potentially helping to personalise treatment.

Population research

When studying a disease that affects so many people, looking for and studying common themes in the population can be incredibly helpful.

Dr David Muller is looking at large numbers of people with kidney cancer to solve some of the mysteries of the disease. For example, he’s investigating the so-called ‘obesity paradox’ – obesity increases the risk of developing kidney cancer, but kidney cancer patients who are obese appear to have a better prognosis than those of a healthy weight. By looking at large numbers of people with kidney cancer he hopes to gather enough information to help reveal why this is.

Dr Evropi Theodoratou and Dr Samantha Quaife are looking at screening, an important tool for detecting certain cancers early, when they’re easier to treat, or helping prevent the diseases altogether. Theodoratou wants to see if some people may benefit from entering bowel cancer screening earlier by identifying those who may be deemed at a higher risk than the general population.

There’s no national lung cancer screening programme in the UK, but there’s plenty of research going on to understand if there would be any benefit to introducing one. Quaife is investigating if people at high risk of lung cancer would go for screening if it was offered, and what barriers there may be to attending. Should a screening programme be introduced, this will help inform how invitations to screening could be designed to improve engagement by those at high risk and to minimise socioeconomic inequalities in participation.

And finally

Dr Harriet Walter is developing the skills to run early stage clinical trials for blood cancers such as leukaemia and lymphoma as well other hard to treat cancers. Researchers like Walter play a vital role in getting new treatments tested, making sure they’re safe and effective, to give people with cancer more treatment options in the future.

Catherine

• If you’re a researcher you can find out more about funding schemes like this on our website.

 

from Cancer Research UK – Science blog http://ift.tt/2xEsqVK

It’s time to welcome a new batch of researchers to the Cancer Research UK team. Here are some common themes they are researching, and how their work could help cancer patients in the future.

Targeting the faulty genetics of cancer

Dr Serena Nik-Zainal is exploring patterns of faults in DNA from cancer cells called signatures. This will help her understand how DNA is damaged inside cells, and how it’s repaired to help cells survive, which can lead to cancer.

Meanwhile, Dr Andrew Beggs, Dr Ross Carruthers, Dr Laureano de la Vega, and Dr Luca Magnani, are looking at the genetic changes that can help tumours become resistant to treatment.

Beggs is using mini lab-grown tumours called organoids to search for new drug targets to stop bowel cancer becoming resistant to treatment. Carruthers is exploring how brain tumours become resistant to radiotherapy. He’s trying to work out how cells from the most aggressive type of brain tumour, glioblastoma, are able to repair their DNA following radiotherapy and keep growing.

Transcription is a process that takes information from genes in our DNA to make proteins. de la Vega is looking at one molecule that controls transcription and has been thought of as protective against cancer. But recent research suggests in some situations it may actually help cancer cells become resistant to chemotherapy – de la Vega is investigating how this happens. Finally, Magnani is looking at way in which some mutations in the tumours are able to turn their genes ‘on’ or ‘off’ to escape treatments and spread around the body, focussing on breast cancer.

Corrupting healthy cells

Many different types of cell live alongside cancer cells and inside tumours as they grow. Dr Ahsan Akram and Professor Tim Underwood are looking at cells called cancer associated fibroblasts, which can help tumours grow and spread.

While Akram is developing a new way to see these cells in lung cancer to help doctors to decide what treatment to give patients, Underwood is trying to understand how oesophageal cancer cells hijack neighbouring healthy cells, and how the genetic changes in the cancer cells help them to do this. Dr Chris Tape is also interested in how the genetic changes in cancer cells help them to corrupt the healthy fibroblast cells and immune cells, focussing on bowel cancer.

Watch how cancer-associated fibroblasts help breast cancer cells spread

An immune attack

Recently, the immune system has emerged as a potentially powerful ally in tackling certain cancers. Dr Sheeba Irshad is investigating how immune cells move within tumours in the lab. By understanding the signals involved, she hopes to find a way to encourage particular immune cells to move into the tumour and kill the cancer cells.

Dr Tobias Janowitz is also investigating new ways to help the immune system tackle pancreatic cancer. He focuses on how tumours change the way that the body uses energy, which can lead to a wasting condition called cachexia. He wants to understand how this hinders the immune response to cancer, which allows the tumour to grow unchecked. By understanding more about these processes in the lab, he hopes to find a way to break this cycle and help tackle pancreatic cancer.

It’s in the blood

Blood stem cells must produce a constant supply of essential blood cells throughout a person’s lifetime, but when their DNA is damaged it can lead to blood cancers.

Dr Meng Wang is investigating how stem cell DNA can be damaged and fixed, which could point to the steps leading to cancer. Meanwhile, Dr Melinda Czeh is looking at how these stem cells change as people get older to try and understand how age increases the risk of acute myeloid leukaemia (AML).

Dr Beth Payne is also looking at what happens as people age in relation to AML, having seen some common genetic faults in older people. She wants to understand how these changes can lead to cancer, which could help identify new potential drug targets.

Evolution of cancer

Cancers cells can be cunning, changing as they evolve and become resistant to treatment. Dr Jyoti Nangalia and Dr Andrea Sottoriva are each taking a different approach to studying this evolution, in the hope of finding new ways to stop cancer in its tracks.

Nangalia is looking for genes that are important in a cancer’s evolution. She wants to predict which patients may be at a higher risk of their disease evolving, giving doctors a head start in planning treatment. Sottoriva is trying to map cancer evolution by taking a mathematical and computational approach. He also wants to anticipate which drugs would be best to give as the disease changes, potentially helping to personalise treatment.

Population research

When studying a disease that affects so many people, looking for and studying common themes in the population can be incredibly helpful.

Dr David Muller is looking at large numbers of people with kidney cancer to solve some of the mysteries of the disease. For example, he’s investigating the so-called ‘obesity paradox’ – obesity increases the risk of developing kidney cancer, but kidney cancer patients who are obese appear to have a better prognosis than those of a healthy weight. By looking at large numbers of people with kidney cancer he hopes to gather enough information to help reveal why this is.

Dr Evropi Theodoratou and Dr Samantha Quaife are looking at screening, an important tool for detecting certain cancers early, when they’re easier to treat, or helping prevent the diseases altogether. Theodoratou wants to see if some people may benefit from entering bowel cancer screening earlier by identifying those who may be deemed at a higher risk than the general population.

There’s no national lung cancer screening programme in the UK, but there’s plenty of research going on to understand if there would be any benefit to introducing one. Quaife is investigating if people at high risk of lung cancer would go for screening if it was offered, and what barriers there may be to attending. Should a screening programme be introduced, this will help inform how invitations to screening could be designed to improve engagement by those at high risk and to minimise socioeconomic inequalities in participation.

And finally

Dr Harriet Walter is developing the skills to run early stage clinical trials for blood cancers such as leukaemia and lymphoma as well other hard to treat cancers. Researchers like Walter play a vital role in getting new treatments tested, making sure they’re safe and effective, to give people with cancer more treatment options in the future.

Catherine

• If you’re a researcher you can find out more about funding schemes like this on our website.

 

from Cancer Research UK – Science blog http://ift.tt/2xEsqVK

Halloween ghost of the summer sun

Every Halloween – and a few days before and after – the brilliant star Arcturus, brightest star in Bootes the Herdsman, sets at the same time and on the same spot on the west-northwest horizon as the summer sun. This star rises at the same time and at the same place on the east-northeast horizon as the summer sun. That’s why – every year at this time – you can consider Arcturus as a ghost of the summer sun.

At mid-northern latitudes, Arcturus now sets about 2 hours after sunset and rises about 2 hours before sunrise.

If you live as far north as Barrow, Alaska, the star Arcturus shines all night long now, mimicking the midnight sun of summer.

If you live in the Southern Hemisphere, you can’t see Arcturus right now. South of the equator, Arcturus sets at the same time and on the same place on the horizon as the winter sun. In other words, Arcturus sets before the sun and rises after the sun at southerly latitudes at this time of year.

If you are in the Northern Hemisphere, try watching this star in the October evening chill. You can envision the absent summer sun radiating its extra hours of sunlight. Not till after dark does this star set, an echo of long summer afternoons. Similarly, Arcturus rises in the east before dawn, a phantom reminder of early morning daybreaks.

At northerly latitudes, Arcturus sets in the west after sunset and rises in the east before sunrise. You can verify that you’re looking at Arcturus once the Big Dipper comes out. Its handle always points to Arcturus.

Halloween – also known as All Hallows’ Eve or All Saints’ Eve – is observed in various countries on October 31, especially in the United States. It’s a big deal for America children, who roam from house to house trick or treating, hoping for candy and other treats.

This modern holiday is based on a much older tradition, that of cross-quarter days.

Cover of ‘Star Arcturus, ghost of summer sun’ coloring book

Bottom line:

Donate: Your support means the world to us

Halloween derived from ancient Celtic cross-quarter day

Enjoying EarthSky so far? Sign up for our free daily newsletter today!

from EarthSky http://ift.tt/1W6SzGH

Every Halloween – and a few days before and after – the brilliant star Arcturus, brightest star in Bootes the Herdsman, sets at the same time and on the same spot on the west-northwest horizon as the summer sun. This star rises at the same time and at the same place on the east-northeast horizon as the summer sun. That’s why – every year at this time – you can consider Arcturus as a ghost of the summer sun.

At mid-northern latitudes, Arcturus now sets about 2 hours after sunset and rises about 2 hours before sunrise.

If you live as far north as Barrow, Alaska, the star Arcturus shines all night long now, mimicking the midnight sun of summer.

If you live in the Southern Hemisphere, you can’t see Arcturus right now. South of the equator, Arcturus sets at the same time and on the same place on the horizon as the winter sun. In other words, Arcturus sets before the sun and rises after the sun at southerly latitudes at this time of year.

If you are in the Northern Hemisphere, try watching this star in the October evening chill. You can envision the absent summer sun radiating its extra hours of sunlight. Not till after dark does this star set, an echo of long summer afternoons. Similarly, Arcturus rises in the east before dawn, a phantom reminder of early morning daybreaks.

At northerly latitudes, Arcturus sets in the west after sunset and rises in the east before sunrise. You can verify that you’re looking at Arcturus once the Big Dipper comes out. Its handle always points to Arcturus.

Halloween – also known as All Hallows’ Eve or All Saints’ Eve – is observed in various countries on October 31, especially in the United States. It’s a big deal for America children, who roam from house to house trick or treating, hoping for candy and other treats.

This modern holiday is based on a much older tradition, that of cross-quarter days.

Cover of ‘Star Arcturus, ghost of summer sun’ coloring book

Bottom line:

Donate: Your support means the world to us

Halloween derived from ancient Celtic cross-quarter day

Enjoying EarthSky so far? Sign up for our free daily newsletter today!

from EarthSky http://ift.tt/1W6SzGH

Star of the week: Algol

The Gorgon Medusa had snakes in place of hair. Eek! Via Wikimedia and Caravaggio

2018 EarthSky lunar calendars are here! Get yours now.

If you were one of the early stargazers, you might have chosen Algol in the constellation Perseus. Early astronomers nicknamed Algol the Demon Star. Bwahaha!

Of course, like all stars, Algol isn’t the least bit scary. But it’s associated in skylore with a mythical scary monster – the Gorgon Medusa – who had snakes instead of hair. It’s said that she was so horrifying in appearance that the sight of her would turn an onlooker to stone.

The star Algol takes its name from an Arabic word meaning “the Demon’s Head.” This star is said to depict the terrifying snake-y head of the Medusa monster.

Perseus and Medusa

In the mythology of the skies, Perseus – a great hero often depicted mounted on Pegasus the Flying Horse – used Medusa’s head to his own advantage – to turn Cetus the Sea-monster into stone. Perhaps the ancients associated this star’s variable brightness with the evil, winking eye of the Medusa.

Winking? Yes. Algol is a known variable star, which waxes and wanes in brightness.

There are many variable stars known throughout the heavens, but Algol might well be the most famous variable star of them all. This star brightens and dims with clockwork regularity, completing one cycle in 2 days 20 hours and 49 minutes. Plus its entire cycle is visible to the eye alone.

The early stargazers surely knew about its changing brightness and must have smiled as they named variable Algol – a strangely behaving star in a sky full of steadily shining stars – for a mythological demon.

How can you see Algol? It’s easy to find. Our sky chart shows the northeastern sky for autumn evenings, especially around Halloween.

How to find Algol

The conspicuous W or M-shaped constellation Cassiopeia enables you to star-hop to Perseus. Draw an imaginary line from the star Gamma Cassiopeia through the star Ruchbah to locate Perseus and then Algol. At mid-northern latitudes, this star can be seen for at least part of the night all year round. But it’s best seen in the evening sky from autumn to spring. It’s visible in the northeast sky in autumn, shines high overhead in winter, and swings to the northwest sky by spring.

Animation of eclipsing binary star via Wikimedia Commons

Algol brightens and dims with clockwork regularity, completing one cycle in 2 days, 20 hours, and 49 minutes. Moreover, this variable star is easy to observe with just the unaided eye. At its brightest, Algol shines about three times more brightly than at its faintest. At maximum brilliance, Algol matches the brightness of the nearby second-magnitude star Almach. At minimum, Algol’s light output fades to that of the star Epsilon Persei.

Almach: Andromeda’s colorful double star

Modern-day astronomy has unlocked the secret of Algol’s mood swings. It’s an eclipsing binary star. This kind of binary is composed of two stars, with each star revolving around the other. From Earth, we see the orbital plane of this binary star almost exactly edge-on. Therefore, when the dimmer of the two stars swings in front of the brighter star, we see Algol at minimum brightness.

from EarthSky http://ift.tt/19gFDW2

The Gorgon Medusa had snakes in place of hair. Eek! Via Wikimedia and Caravaggio

2018 EarthSky lunar calendars are here! Get yours now.

If you were one of the early stargazers, you might have chosen Algol in the constellation Perseus. Early astronomers nicknamed Algol the Demon Star. Bwahaha!

Of course, like all stars, Algol isn’t the least bit scary. But it’s associated in skylore with a mythical scary monster – the Gorgon Medusa – who had snakes instead of hair. It’s said that she was so horrifying in appearance that the sight of her would turn an onlooker to stone.

The star Algol takes its name from an Arabic word meaning “the Demon’s Head.” This star is said to depict the terrifying snake-y head of the Medusa monster.

Perseus and Medusa

In the mythology of the skies, Perseus – a great hero often depicted mounted on Pegasus the Flying Horse – used Medusa’s head to his own advantage – to turn Cetus the Sea-monster into stone. Perhaps the ancients associated this star’s variable brightness with the evil, winking eye of the Medusa.

Winking? Yes. Algol is a known variable star, which waxes and wanes in brightness.

There are many variable stars known throughout the heavens, but Algol might well be the most famous variable star of them all. This star brightens and dims with clockwork regularity, completing one cycle in 2 days 20 hours and 49 minutes. Plus its entire cycle is visible to the eye alone.

The early stargazers surely knew about its changing brightness and must have smiled as they named variable Algol – a strangely behaving star in a sky full of steadily shining stars – for a mythological demon.

How can you see Algol? It’s easy to find. Our sky chart shows the northeastern sky for autumn evenings, especially around Halloween.

How to find Algol

The conspicuous W or M-shaped constellation Cassiopeia enables you to star-hop to Perseus. Draw an imaginary line from the star Gamma Cassiopeia through the star Ruchbah to locate Perseus and then Algol. At mid-northern latitudes, this star can be seen for at least part of the night all year round. But it’s best seen in the evening sky from autumn to spring. It’s visible in the northeast sky in autumn, shines high overhead in winter, and swings to the northwest sky by spring.

Animation of eclipsing binary star via Wikimedia Commons

Algol brightens and dims with clockwork regularity, completing one cycle in 2 days, 20 hours, and 49 minutes. Moreover, this variable star is easy to observe with just the unaided eye. At its brightest, Algol shines about three times more brightly than at its faintest. At maximum brilliance, Algol matches the brightness of the nearby second-magnitude star Almach. At minimum, Algol’s light output fades to that of the star Epsilon Persei.

Almach: Andromeda’s colorful double star

Modern-day astronomy has unlocked the secret of Algol’s mood swings. It’s an eclipsing binary star. This kind of binary is composed of two stars, with each star revolving around the other. From Earth, we see the orbital plane of this binary star almost exactly edge-on. Therefore, when the dimmer of the two stars swings in front of the brighter star, we see Algol at minimum brightness.

from EarthSky http://ift.tt/19gFDW2

Smokey sunset skies over Italy

October 29, 2017 photo by Elena Gissi in Lisanza, Lombardy, Italy.

Over the past couple of weeks, as firefighters have struggled to contain them, wildfires have raged in northern Italy. We received two photos of the unusual sunset skies over northern Italy on October 29, 2017. First, Elena Gissi in Lisanza, Lombardy, Italy wrote:

This photo is not post-processed. The sky was really like this, and one of reasons is the abundance of small particles caused by forest fires occurring some 100 kilometers [60 miles] westward.

Good for photographers… Only for them, though.

Why does the sky look like this? It looks as if there’s actual smoke in the air, for one thing. Also, an intense red sunset can result when smoke particles filter out the shorter-wavelength colors in sunlight – the greens, blues, yellows and purples – and leave the red and orange colors behind. I wonder if, since the rate of wildfires has been increasing globally, someone will coin a name for these swirling, intense red sunset skies occurring near fire sites. We’ve seen multiple photos of them this year, from various spots around the globe. Read more about the way air, dust, aerosols and water drops scatter and absorb the rays throughout their long passage through the atmosphere at sunset, at Atmospheric Optics.

More about Rayleigh scattering, which is the reason for the intense red color here.

Sometimes wildfire smoke can also get into the upper troposphere or stratosphere and be carried large distances, to create red skies and sunsets.

It’s also common, near the sites of wildfires, to see red moons and suns. Read more, plus red moon and sun photos, here.

Matteo Curatitoli, whose photo is below, also caught the October 29 sunset. Thank you, Elena and Matteo. We hope the fires are brought under control soon.

Matteo Curatitoli in Ghemme, Piedmont, Italy wrote of the October 29 sunset: “… north Italy’s skies were amazing! It was like someone had painted sand dunes on the sky!”

Bottom line: Swirling, intense red sunset skies due to ongoing wildfires in northern Italy.

from EarthSky http://ift.tt/2iO5DnT

October 29, 2017 photo by Elena Gissi in Lisanza, Lombardy, Italy.

Over the past couple of weeks, as firefighters have struggled to contain them, wildfires have raged in northern Italy. We received two photos of the unusual sunset skies over northern Italy on October 29, 2017. First, Elena Gissi in Lisanza, Lombardy, Italy wrote:

This photo is not post-processed. The sky was really like this, and one of reasons is the abundance of small particles caused by forest fires occurring some 100 kilometers [60 miles] westward.

Good for photographers… Only for them, though.

Why does the sky look like this? It looks as if there’s actual smoke in the air, for one thing. Also, an intense red sunset can result when smoke particles filter out the shorter-wavelength colors in sunlight – the greens, blues, yellows and purples – and leave the red and orange colors behind. I wonder if, since the rate of wildfires has been increasing globally, someone will coin a name for these swirling, intense red sunset skies occurring near fire sites. We’ve seen multiple photos of them this year, from various spots around the globe. Read more about the way air, dust, aerosols and water drops scatter and absorb the rays throughout their long passage through the atmosphere at sunset, at Atmospheric Optics.

More about Rayleigh scattering, which is the reason for the intense red color here.

Sometimes wildfire smoke can also get into the upper troposphere or stratosphere and be carried large distances, to create red skies and sunsets.

It’s also common, near the sites of wildfires, to see red moons and suns. Read more, plus red moon and sun photos, here.

Matteo Curatitoli, whose photo is below, also caught the October 29 sunset. Thank you, Elena and Matteo. We hope the fires are brought under control soon.

Matteo Curatitoli in Ghemme, Piedmont, Italy wrote of the October 29 sunset: “… north Italy’s skies were amazing! It was like someone had painted sand dunes on the sky!”

Bottom line: Swirling, intense red sunset skies due to ongoing wildfires in northern Italy.

from EarthSky http://ift.tt/2iO5DnT

The Science Behind Pumpkin Chucking

What do ancient Greek artillery, materials engineering and pumpkin chucking have in common?

from http://ift.tt/2lsetZH

What do ancient Greek artillery, materials engineering and pumpkin chucking have in common?

from http://ift.tt/2lsetZH

What is dark matter?

Map of all matter – most of which is invisible dark matter – between Earth and the edge of the observable universe. Image via ESA/NASA/JPL-Caltech.

By Dan Hooper, University of Chicago

The past few decades have ushered in an amazing era in the science of cosmology. A diverse array of high-precision measurements has allowed us to reconstruct our universe’s history in remarkable detail.

And when we compare different measurements – of the expansion rate of the universe, the patterns of light released in the formation of the first atoms, the distributions in space of galaxies and galaxy clusters and the abundances of various chemical species – we find that they all tell the same story, and all support the same series of events.

This line of research has, frankly, been more successful than I think we had any right to have hoped. We know more about the origin and history of our universe today than almost anyone a few decades ago would have guessed that we would learn in such a short time.

But despite these very considerable successes, there remains much more to be learned. And in some ways, the discoveries made in recent decades have raised as many new questions as they have answered.

One of the most vexing gets at the heart of what our universe is actually made of. Cosmological observations have determined the average density of matter in our universe to very high precision. But this density turns out to be much greater than can be accounted for with ordinary atoms.

After decades of measurements and debate, we are now confident that the overwhelming majority of our universe’s matter – about 84 percent – is not made up of atoms, or of any other known substance. Although we can feel the gravitational pull of this other matter, and clearly tell that it’s there, we simply do not know what it is. This mysterious stuff is invisible, or at least nearly so. For lack of a better name, we call it “dark matter.” But naming something is very different from understanding it.

Astronomers map dark matter indirectly, via its gravitational pull on other objects. Image via NASA, ESA, and D. Coe (NASA JPL/Caltech and STScI).

For almost as long as we’ve known that dark matter exists, physicists and astronomers have been devising ways to try to learn what it’s made of. They’ve built ultra-sensitive detectors, deployed in deep underground mines, in an effort to measure the gentle impacts of individual dark matter particles colliding with atoms.

They’ve built exotic telescopes – sensitive not to optical light but to less familiar gamma rays, cosmic rays and neutrinos – to search for the high-energy radiation that is thought to be generated through the interactions of dark matter particles.

And we have searched for signs of dark matter using incredible machines which accelerate beams of particles – typically protons or electrons – up to the highest speeds possible, and then smash them into one another in an effort to convert their energy into matter. The idea is these collisions could create new and exotic substances, perhaps including the kinds of particles that make up the dark matter of our universe.

As recently as a decade ago, most cosmologists – including myself – were reasonably confident that we would soon begin to solve the puzzle of dark matter. After all, there was an ambitious experimental program on the horizon, which we anticipated would enable us to identify the nature of this substance and to begin to measure its properties. This program included the world’s most powerful particle accelerator – the Large Hadron Collider – as well as an array of other new experiments and powerful telescopes.

Experiments at CERN are trying to zero in on dark matter – but so far no dice. Image via CERN.

But things did not play out the way that we expected them to. Although these experiments and observations have been carried out as well as or better than we could have hoped, the discoveries did not come.

Over the past 15 years, for example, experiments designed to detect individual particles of dark matter have become a million times more sensitive, and yet no signs of these elusive particles have appeared. And although the Large Hadron Collider has by all technical standards performed beautifully, with the exception of the Higgs boson, no new particles or other phenomena have been discovered.

At Fermilab, the Cryogenic Dark Matter Search uses towers of disks made from silicon and germanium to search for particle interactions from dark matter. Image via Reidar Hahn/Fermilab.

The stubborn elusiveness of dark matter has left many scientists both surprised and confused. We had what seemed like very good reasons to expect particles of dark matter to be discovered by now. And yet the hunt continues, and the mystery deepens.

In many ways, we have only more open questions now than we did a decade or two ago. And at times, it can seem that the more precisely we measure our universe, the less we understand it. Throughout the second half of the 20th century, theoretical particle physicists were often very successful at predicting the kinds of particles that would be discovered as accelerators became increasingly powerful. It was a truly impressive run.

But our prescience seems to have come to an end – the long-predicted particles associated with our favorite and most well-motivated theories have stubbornly refused to appear. Perhaps the discoveries of such particles are right around the corner, and our confidence will soon be restored. But right now, there seems to be little support for such optimism.

In response, droves of physicists are going back to their chalkboards, revisiting and revising their assumptions. With bruised egos and a bit more humility, we are desperately attempting to find a new way to make sense of our world.

Dan Hooper, Associate Scientist in Theoretical Astrophysics at Fermi National Accelerator Laboratory and Associate Professor of Astronomy and Astrophysics, University of Chicago

This article was originally published on The Conversation. Read the original article.

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

Map of all matter – most of which is invisible dark matter – between Earth and the edge of the observable universe. Image via ESA/NASA/JPL-Caltech.

By Dan Hooper, University of Chicago

The past few decades have ushered in an amazing era in the science of cosmology. A diverse array of high-precision measurements has allowed us to reconstruct our universe’s history in remarkable detail.

And when we compare different measurements – of the expansion rate of the universe, the patterns of light released in the formation of the first atoms, the distributions in space of galaxies and galaxy clusters and the abundances of various chemical species – we find that they all tell the same story, and all support the same series of events.

This line of research has, frankly, been more successful than I think we had any right to have hoped. We know more about the origin and history of our universe today than almost anyone a few decades ago would have guessed that we would learn in such a short time.

But despite these very considerable successes, there remains much more to be learned. And in some ways, the discoveries made in recent decades have raised as many new questions as they have answered.

One of the most vexing gets at the heart of what our universe is actually made of. Cosmological observations have determined the average density of matter in our universe to very high precision. But this density turns out to be much greater than can be accounted for with ordinary atoms.

After decades of measurements and debate, we are now confident that the overwhelming majority of our universe’s matter – about 84 percent – is not made up of atoms, or of any other known substance. Although we can feel the gravitational pull of this other matter, and clearly tell that it’s there, we simply do not know what it is. This mysterious stuff is invisible, or at least nearly so. For lack of a better name, we call it “dark matter.” But naming something is very different from understanding it.

Astronomers map dark matter indirectly, via its gravitational pull on other objects. Image via NASA, ESA, and D. Coe (NASA JPL/Caltech and STScI).

For almost as long as we’ve known that dark matter exists, physicists and astronomers have been devising ways to try to learn what it’s made of. They’ve built ultra-sensitive detectors, deployed in deep underground mines, in an effort to measure the gentle impacts of individual dark matter particles colliding with atoms.

They’ve built exotic telescopes – sensitive not to optical light but to less familiar gamma rays, cosmic rays and neutrinos – to search for the high-energy radiation that is thought to be generated through the interactions of dark matter particles.

And we have searched for signs of dark matter using incredible machines which accelerate beams of particles – typically protons or electrons – up to the highest speeds possible, and then smash them into one another in an effort to convert their energy into matter. The idea is these collisions could create new and exotic substances, perhaps including the kinds of particles that make up the dark matter of our universe.

As recently as a decade ago, most cosmologists – including myself – were reasonably confident that we would soon begin to solve the puzzle of dark matter. After all, there was an ambitious experimental program on the horizon, which we anticipated would enable us to identify the nature of this substance and to begin to measure its properties. This program included the world’s most powerful particle accelerator – the Large Hadron Collider – as well as an array of other new experiments and powerful telescopes.

Experiments at CERN are trying to zero in on dark matter – but so far no dice. Image via CERN.

But things did not play out the way that we expected them to. Although these experiments and observations have been carried out as well as or better than we could have hoped, the discoveries did not come.

Over the past 15 years, for example, experiments designed to detect individual particles of dark matter have become a million times more sensitive, and yet no signs of these elusive particles have appeared. And although the Large Hadron Collider has by all technical standards performed beautifully, with the exception of the Higgs boson, no new particles or other phenomena have been discovered.

At Fermilab, the Cryogenic Dark Matter Search uses towers of disks made from silicon and germanium to search for particle interactions from dark matter. Image via Reidar Hahn/Fermilab.

The stubborn elusiveness of dark matter has left many scientists both surprised and confused. We had what seemed like very good reasons to expect particles of dark matter to be discovered by now. And yet the hunt continues, and the mystery deepens.

In many ways, we have only more open questions now than we did a decade or two ago. And at times, it can seem that the more precisely we measure our universe, the less we understand it. Throughout the second half of the 20th century, theoretical particle physicists were often very successful at predicting the kinds of particles that would be discovered as accelerators became increasingly powerful. It was a truly impressive run.

But our prescience seems to have come to an end – the long-predicted particles associated with our favorite and most well-motivated theories have stubbornly refused to appear. Perhaps the discoveries of such particles are right around the corner, and our confidence will soon be restored. But right now, there seems to be little support for such optimism.

In response, droves of physicists are going back to their chalkboards, revisiting and revising their assumptions. With bruised egos and a bit more humility, we are desperately attempting to find a new way to make sense of our world.

Dan Hooper, Associate Scientist in Theoretical Astrophysics at Fermi National Accelerator Laboratory and Associate Professor of Astronomy and Astrophysics, University of Chicago

This article was originally published on The Conversation. Read the original article.

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