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2017 SkS Weekly Climate Change & Global Warming Digest #37

Story of the Week... El Niño/La Niña Update... Toon of the Week... Quote of the Week... SkS in the News... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

The Window Is Closing to Avoid Dangerous Global Warming

Climate Change 

Credit: David McNew Getty Images 

Deadly climate change could threaten most of the world's human population by the end of this century without efforts well beyond those captured in the Paris Agreement.

That's the finding of a pair of related reports released yesterday by an international group of climate science and policy luminaries who warned that the window is closing to avert dangerous warming. They say carbon dioxide might have to be removed from the atmosphere.

Scientists Yangyang Xu and Veerabhadran Ramanathan found in a paper published in the Proceedings of the National Academy of Sciences (PNAS) that there already exists a 1 in 20 chance that the 2.2 trillion tons of carbon dioxide in the Earth's atmosphere could cause an existential warming threat. This "fat tail" scenario would mean the world experiences "existential/unknown" warming by 2100 — defined in the report as more than 5 degrees Celsius above preindustrial levels.

The Window Is Closing to Avoid Dangerous Global Warming by Jean Chemnick, ClimateWire/Scientific American, Sep 15, 2017

El Niño/La Niña Update

La Niña is now increasingly possible in the next few months, according to a new reportreleased by NOAA, and may have some impacts on weather in the United States in the fall and winter.

La Niña May Develop By Fall or Winter, NOAA Says; Here's What That Could Mean by Jonathan Erdman, Sep 13, 2017 

Toon of the Week...

2017 Toon 37 

Quote of the Week...

That is one reason many scientists maintain it is critical to use the megaphone that the dual devastation of Hurricane Harvey and Hurricane Irma has provided. People, they note, are finally paying attention.

“We know that as humans, we are all too good at pretending like a risk, even one we know is real, doesn’t matter to us,” Katharine Hayhoe, an atmospheric scientist at Texas Tech University, wrote in an email as Harvey lashed the Texas coast.

“When we try to warn people about the risks, there’s no ‘news’ hook. No one wants to listen. That’s why the time to talk about it is now,” Dr. Hayhoe said. “The most pernicious and dangerous myth we’ve bought into when it comes to climate change is not the myth that it isn’t real or humans aren’t responsible. It’s the myth that it doesn’t matter to me. And that is exactly the myth that Harvey shatters.”

Hurricane Irma Linked to Climate Change? For Some, a Very ‘Insensitive’ Question. by Lisa Friedman, Climate, New York Times, Sep 11, 2017 

SkS in the News...

In her Washington Post Right Turn Op-ed, Will Harvey and Irma be a wake-up call?, Jennifer Rubin wrote:

And yet Republicans from Texas (both U.S. senators and a slew of congressmen), Florida (most especially Gov. Rick Scott and Sen. Marco Rubio), Alabama and Louisiana, among other locales, refuse to acknowledge the clear cause of rising sea levels and temperatures that add to the destructiveness of hurricanes that devastate their states. The GOP pols like to dodge the question by saying they are not climate scientists — and then refuse to accept the findings of 97 percent of the scientific community. Bluntly put, they’d rather cling to their know-nothingism than take steps to abate a known danger to their states. How is that any different from refusing to build levees and pumps or update building standards? (Of course, the climate-change denier in chief did cancel a flood regulation that took account of global warming, something he should be asked about when he goes for his next photo op.) 

Coming Soon on SkS...

  • Scientific models saved lives from Harvey and Irma. They can from climate change too (Dana)
  • Australia's Transition to Renewable Energy (Agnostic)
  • New research, September 4-10, 2017 (Ari Jokimäki)
  • Guest Post (John Abraham)
  • Why the 97% climate consensus is important (Dana, John Cook, Sander van der Linden, Ed Maibach, Tony Lieserowitz)
  • 2017 SkS Weekly Climate Change & Global Warming News Roundup #38 (John Hartz)
  • 2017 SkS Weekly Climate Change & Global Waming Digest #38 (John Hartz)

Poster of the Week...

2017 Poster 37 

Climate Feedback Reviews...

Climate Feedback asked its network of scientists to review the article, Has Climate Change Intensified 2017’s Western Wildfires? by Robinson Meyer, The Atlantic, Sep 7, 2017.

Three scientists analyzed the article and estimate its overall scientific credibility to be ‘very high’.

A majority of reviewers tagged the article as: Accurate, Insightful, Sound reasoning

Review Summary

This story in The Atlantic describes the conditions that have contributed to this year’s widespread wildfires in the western United States, including the influence of a changing climate.

Scientists who reviewed the story found that it was an accurate summary of the factors involved in this fire season—warm temperatures as well as past fire-suppression practices that have increased the density of fuel available for fires to burn. 

SkS Week in Review... 

97 Hours of Consensus...

Julienne Stroeve 

 

Julienne Stroeve's bio page & Quote source 

High resolution JPEG (1024 pixels wide)



from Skeptical Science http://ift.tt/2xIJtd1

Story of the Week... El Niño/La Niña Update... Toon of the Week... Quote of the Week... SkS in the News... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

The Window Is Closing to Avoid Dangerous Global Warming

Climate Change 

Credit: David McNew Getty Images 

Deadly climate change could threaten most of the world's human population by the end of this century without efforts well beyond those captured in the Paris Agreement.

That's the finding of a pair of related reports released yesterday by an international group of climate science and policy luminaries who warned that the window is closing to avert dangerous warming. They say carbon dioxide might have to be removed from the atmosphere.

Scientists Yangyang Xu and Veerabhadran Ramanathan found in a paper published in the Proceedings of the National Academy of Sciences (PNAS) that there already exists a 1 in 20 chance that the 2.2 trillion tons of carbon dioxide in the Earth's atmosphere could cause an existential warming threat. This "fat tail" scenario would mean the world experiences "existential/unknown" warming by 2100 — defined in the report as more than 5 degrees Celsius above preindustrial levels.

The Window Is Closing to Avoid Dangerous Global Warming by Jean Chemnick, ClimateWire/Scientific American, Sep 15, 2017

El Niño/La Niña Update

La Niña is now increasingly possible in the next few months, according to a new reportreleased by NOAA, and may have some impacts on weather in the United States in the fall and winter.

La Niña May Develop By Fall or Winter, NOAA Says; Here's What That Could Mean by Jonathan Erdman, Sep 13, 2017 

Toon of the Week...

2017 Toon 37 

Quote of the Week...

That is one reason many scientists maintain it is critical to use the megaphone that the dual devastation of Hurricane Harvey and Hurricane Irma has provided. People, they note, are finally paying attention.

“We know that as humans, we are all too good at pretending like a risk, even one we know is real, doesn’t matter to us,” Katharine Hayhoe, an atmospheric scientist at Texas Tech University, wrote in an email as Harvey lashed the Texas coast.

“When we try to warn people about the risks, there’s no ‘news’ hook. No one wants to listen. That’s why the time to talk about it is now,” Dr. Hayhoe said. “The most pernicious and dangerous myth we’ve bought into when it comes to climate change is not the myth that it isn’t real or humans aren’t responsible. It’s the myth that it doesn’t matter to me. And that is exactly the myth that Harvey shatters.”

Hurricane Irma Linked to Climate Change? For Some, a Very ‘Insensitive’ Question. by Lisa Friedman, Climate, New York Times, Sep 11, 2017 

SkS in the News...

In her Washington Post Right Turn Op-ed, Will Harvey and Irma be a wake-up call?, Jennifer Rubin wrote:

And yet Republicans from Texas (both U.S. senators and a slew of congressmen), Florida (most especially Gov. Rick Scott and Sen. Marco Rubio), Alabama and Louisiana, among other locales, refuse to acknowledge the clear cause of rising sea levels and temperatures that add to the destructiveness of hurricanes that devastate their states. The GOP pols like to dodge the question by saying they are not climate scientists — and then refuse to accept the findings of 97 percent of the scientific community. Bluntly put, they’d rather cling to their know-nothingism than take steps to abate a known danger to their states. How is that any different from refusing to build levees and pumps or update building standards? (Of course, the climate-change denier in chief did cancel a flood regulation that took account of global warming, something he should be asked about when he goes for his next photo op.) 

Coming Soon on SkS...

  • Scientific models saved lives from Harvey and Irma. They can from climate change too (Dana)
  • Australia's Transition to Renewable Energy (Agnostic)
  • New research, September 4-10, 2017 (Ari Jokimäki)
  • Guest Post (John Abraham)
  • Why the 97% climate consensus is important (Dana, John Cook, Sander van der Linden, Ed Maibach, Tony Lieserowitz)
  • 2017 SkS Weekly Climate Change & Global Warming News Roundup #38 (John Hartz)
  • 2017 SkS Weekly Climate Change & Global Waming Digest #38 (John Hartz)

Poster of the Week...

2017 Poster 37 

Climate Feedback Reviews...

Climate Feedback asked its network of scientists to review the article, Has Climate Change Intensified 2017’s Western Wildfires? by Robinson Meyer, The Atlantic, Sep 7, 2017.

Three scientists analyzed the article and estimate its overall scientific credibility to be ‘very high’.

A majority of reviewers tagged the article as: Accurate, Insightful, Sound reasoning

Review Summary

This story in The Atlantic describes the conditions that have contributed to this year’s widespread wildfires in the western United States, including the influence of a changing climate.

Scientists who reviewed the story found that it was an accurate summary of the factors involved in this fire season—warm temperatures as well as past fire-suppression practices that have increased the density of fuel available for fires to burn. 

SkS Week in Review... 

97 Hours of Consensus...

Julienne Stroeve 

 

Julienne Stroeve's bio page & Quote source 

High resolution JPEG (1024 pixels wide)



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Astronomers find a pitch-black planet

Artist’s concept of WASP-12b, a world that traps most of the visible light falling into its atmosphere and so appears black. Image via HubbleSite.

The Hubble Space Telescope has observed an exoplanet – or planet orbiting a distant star – that looks as black as fresh asphalt. The planet is called WASP-12b, and it’s one of a class of so-called hot Jupiters, gigantic, gaseous planets orbiting close to their host stars and thereby heated to extreme temperatures. The astronomers say this planet is so black because it absorbs some 94 percent of the visible starlight falling into its atmosphere, rather than reflecting it back into space. Their work was published online on September 14, 2017 by the peer-reviewed journal Astrophysical Journal Letters. A statement from HubbleSite said:

The planet’s atmosphere is so hot that most molecules are unable to survive on the blistering day side of the planet, where the temperature is 4,600 degrees Fahrenheit. Therefore, clouds probably cannot form to reflect light back into space. Instead, incoming light penetrates deep into the planet’s atmosphere where it is absorbed by hydrogen atoms and converted to heat energy.

This planet is about 1,400 light-years away. It orbits a sunlike star, located in our sky in the direction of the constellation Auriga the Charioteer. Astronomer Taylor Bell of McGill University and the Institute for Research on Exoplanets in Montreal, Quebec, Canada, is lead researcher of the Hubble study. He said:

We did not expect to find such a dark exoplanet. Most hot Jupiters reflect about 40 percent of starlight.

WASP-12b is about 2 million miles (3 million km) from its star. It has a fixed day side and night side; that is, it orbits so near its star that it’s tidally locked to the star, much as our moon is tidally locked to Earth and thus keeps a single face turned perpetually toward our planet. The night side of WASP-12b is more than 2,000 degrees Fahrenheit cooler than the day side. Water vapor exists in the atmosphere on the night side, and clouds do form. Previous Hubble observations of the day/night boundary detected evidence of water vapor and possibly clouds and hazes in the atmosphere. Bell said:

This new Hubble research further demonstrates the vast diversity among the strange population of hot Jupiters. You can have planets like WASP-12b that are 4,600 degrees Fahrenheit and some that are 2,200 degrees Fahrenheit, and they’re both called hot Jupiters. Past observations of hot Jupiters indicate that the temperature difference between the day and night sides of the planet increases with hotter day sides. This previous research suggests that more heat is being pumped into the day side of the planet, but the processes, such as winds, that carry the heat to the night side of the planet don’t keep up the pace.

These astronomers used the Hubble’s Space Telescope Imaging Spectrograph to search in mostly visible light for a tiny dip in starlight as the planet passed directly behind the star. The amount of dimming tells astronomers how much reflected light is given off by the planet. However, the observations did not detect reflected light, meaning that the daytime side of the planet is absorbing almost all the starlight falling onto it.

Bottom line: Astronomers used the Hubble Space Telescope to study the exoplanet WASP-12b and found that is absorbs most starlight falling onto it, so that it is “as black as fresh asphalt.”

Via HubbleSite



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

Artist’s concept of WASP-12b, a world that traps most of the visible light falling into its atmosphere and so appears black. Image via HubbleSite.

The Hubble Space Telescope has observed an exoplanet – or planet orbiting a distant star – that looks as black as fresh asphalt. The planet is called WASP-12b, and it’s one of a class of so-called hot Jupiters, gigantic, gaseous planets orbiting close to their host stars and thereby heated to extreme temperatures. The astronomers say this planet is so black because it absorbs some 94 percent of the visible starlight falling into its atmosphere, rather than reflecting it back into space. Their work was published online on September 14, 2017 by the peer-reviewed journal Astrophysical Journal Letters. A statement from HubbleSite said:

The planet’s atmosphere is so hot that most molecules are unable to survive on the blistering day side of the planet, where the temperature is 4,600 degrees Fahrenheit. Therefore, clouds probably cannot form to reflect light back into space. Instead, incoming light penetrates deep into the planet’s atmosphere where it is absorbed by hydrogen atoms and converted to heat energy.

This planet is about 1,400 light-years away. It orbits a sunlike star, located in our sky in the direction of the constellation Auriga the Charioteer. Astronomer Taylor Bell of McGill University and the Institute for Research on Exoplanets in Montreal, Quebec, Canada, is lead researcher of the Hubble study. He said:

We did not expect to find such a dark exoplanet. Most hot Jupiters reflect about 40 percent of starlight.

WASP-12b is about 2 million miles (3 million km) from its star. It has a fixed day side and night side; that is, it orbits so near its star that it’s tidally locked to the star, much as our moon is tidally locked to Earth and thus keeps a single face turned perpetually toward our planet. The night side of WASP-12b is more than 2,000 degrees Fahrenheit cooler than the day side. Water vapor exists in the atmosphere on the night side, and clouds do form. Previous Hubble observations of the day/night boundary detected evidence of water vapor and possibly clouds and hazes in the atmosphere. Bell said:

This new Hubble research further demonstrates the vast diversity among the strange population of hot Jupiters. You can have planets like WASP-12b that are 4,600 degrees Fahrenheit and some that are 2,200 degrees Fahrenheit, and they’re both called hot Jupiters. Past observations of hot Jupiters indicate that the temperature difference between the day and night sides of the planet increases with hotter day sides. This previous research suggests that more heat is being pumped into the day side of the planet, but the processes, such as winds, that carry the heat to the night side of the planet don’t keep up the pace.

These astronomers used the Hubble’s Space Telescope Imaging Spectrograph to search in mostly visible light for a tiny dip in starlight as the planet passed directly behind the star. The amount of dimming tells astronomers how much reflected light is given off by the planet. However, the observations did not detect reflected light, meaning that the daytime side of the planet is absorbing almost all the starlight falling onto it.

Bottom line: Astronomers used the Hubble Space Telescope to study the exoplanet WASP-12b and found that is absorbs most starlight falling onto it, so that it is “as black as fresh asphalt.”

Via HubbleSite



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See it! Dance of planets before dawn

Steven Arthur Sweet of Lunar 101 Moon Book wrote: “The Sickle of Leo, Venus, Mars, Mercury and a crescent moon. Sept 17, 2017. Bloordale Park, Toronto.”

David Rojas captured the planets on September 17 and wrote: “Conjunction of the moon, the planets Venus, Mars, Mercury and the star Regulus of this day, before dawn. Tomorrow these same stars will be seen in a closer conjunction. The following capture was made from the city of Guatemala. Greetings.”

September 17, 2017 moon and Venus … caught by Hope Carter in Martin, Michigan. She wrote: “The glow from the rising sun (still below the horizon here) painted the clouds a delicate shade of pink, making for a beautiful morning here in west Michigan to watch the moon and Venus rise together in the eastern sky.”

Eliot Herman in Tucson, Arizona caught the Mercury/ Mars conjunction on September 16. Moon inset for size comparison. He wrote: “Captured with a Vixen VSD telescope and a Nikon D810 camera mounted on a stationary tripod … Mercury above and Mars below.” By the way, both appear reddish, especially if you view larger. Mars really is red in color, but Mercury isn’t. In Mercury’s case, the red color often comes from seeing it low in the sky, where we peer at it through an extra thickness of Earth’s atmosphere (same reason a sunset or moonrise looks red).

“What a beautiful show at dawn in the sky of Meaux, France,” wrote Patrick Casaert of LaLuneTheMoon on Facebook, on September 16.

Planets on the morning of September 13, 2017 via Malcom Wilton-Jone in Valencia, Spain.

Mario Pereira in Felgueiras, Portugal caught bright Venus – and much fainter Mercury and Mars – on the morning of September 12, 2017. The star Regulus in the constellation Leo also lies along this line.



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Steven Arthur Sweet of Lunar 101 Moon Book wrote: “The Sickle of Leo, Venus, Mars, Mercury and a crescent moon. Sept 17, 2017. Bloordale Park, Toronto.”

David Rojas captured the planets on September 17 and wrote: “Conjunction of the moon, the planets Venus, Mars, Mercury and the star Regulus of this day, before dawn. Tomorrow these same stars will be seen in a closer conjunction. The following capture was made from the city of Guatemala. Greetings.”

September 17, 2017 moon and Venus … caught by Hope Carter in Martin, Michigan. She wrote: “The glow from the rising sun (still below the horizon here) painted the clouds a delicate shade of pink, making for a beautiful morning here in west Michigan to watch the moon and Venus rise together in the eastern sky.”

Eliot Herman in Tucson, Arizona caught the Mercury/ Mars conjunction on September 16. Moon inset for size comparison. He wrote: “Captured with a Vixen VSD telescope and a Nikon D810 camera mounted on a stationary tripod … Mercury above and Mars below.” By the way, both appear reddish, especially if you view larger. Mars really is red in color, but Mercury isn’t. In Mercury’s case, the red color often comes from seeing it low in the sky, where we peer at it through an extra thickness of Earth’s atmosphere (same reason a sunset or moonrise looks red).

“What a beautiful show at dawn in the sky of Meaux, France,” wrote Patrick Casaert of LaLuneTheMoon on Facebook, on September 16.

Planets on the morning of September 13, 2017 via Malcom Wilton-Jone in Valencia, Spain.

Mario Pereira in Felgueiras, Portugal caught bright Venus – and much fainter Mercury and Mars – on the morning of September 12, 2017. The star Regulus in the constellation Leo also lies along this line.



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How to see binocular comet C/2017 O1

Comet C/2017 01 as captured by Rolando Ligustri in Italy.

A recently discovered comet – although not visible to the eye alone – is becoming bright enough to view with small telescopes and binoculars. Comet C/2017 O1 (ASASSN1) is a long-period comet – presumably from the Oort Comet Cloud surrounding our solar system – first detected on July 19, 2017 from the All Sky Automated Survey for Supernovae from Cerro Tololo, Chile. In fact, it was the first comet detected by this survey. The comet had an outburst shortly after discovery and has been getting brighter, and – if you have a small telescope or good binoculars – you can start watching it now. During most of September, Comet C/2017 O1 is in front of the constellation of Taurus and shows a brightness or magnitude of 9.5.

An orbit analysis of this celestial visitor indicates it will be at perihelion, or closest to the sun, on October 14, 2017. It’ll be closest to Earth on October 18, passing distantly at about 67 million miles (108 million km) from our planet.

Comet C/2017 O1 (ASASSN1) discovery image on July 19, 2017 plus 2 more dates. The comet was at a faint magnitude +15.3 at discovery. It quickly jumped 100 times in brightness – via an outburst – to magnitude +10. In October, it’s hoped the comet will be around magnitude 8, within reach of binoculars and small telescopes. Image via Benjamin Shappee/ Wikimedia Commons.

Although comets are unpredictable, recent observations show that C2017 O1 has brightened. It is not expected to become visible to the unaided eye, but the comet may reach a magnitude of around 8. If so, it’ll be well within reach of binoculars and small telescopes.

Binoculars should reveal it as a small fuzzy patch of light in the sky. Some observers may see a hint of green color in the comet, which is caused by gases like diatomic carbon.

Late on the night of Saturday, September 16, the comet was located below the familiar stars of the Pleiades cluster, a group of stars visible to the naked eye to the east shortly after midnight, as seen from central US.

Late on the night of Saturday, September 30, comet C/2017 O1 is located between the bright star Capella, in Auriga, and the Pleiades star cluster, as seen from central US. Illustration by Eddie Irizarry using Stellarium.

Location of comet C/2017 O1 during closest approach to Earth on October 18, 2017, as seen from central U.S., facing northeast. Illustration by Eddie Irizarry using Stellarium.

On the night of October 28, 2017 , comet C/2017 O1 passes close to star alpha Cam (HIP 22783), the brightest star of the constellation Camelopardalis. This 4th magnitude star is barely visible to the unaided eye. Illustration by Eddie Irizarry using Stellarium.

Although comet C/2017 O1 should be dimmer by December 1, 2017 , during the last month of this year the celestial visitor will be located close to Polaris, the north star. Illustration by Eddie Irizarry using Stellarium.

Also, see the comet’s page at TheSkyLive.

Bottom line: Charts that can help you find long-period comet C/2017 O1 (ASASSN1).



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Comet C/2017 01 as captured by Rolando Ligustri in Italy.

A recently discovered comet – although not visible to the eye alone – is becoming bright enough to view with small telescopes and binoculars. Comet C/2017 O1 (ASASSN1) is a long-period comet – presumably from the Oort Comet Cloud surrounding our solar system – first detected on July 19, 2017 from the All Sky Automated Survey for Supernovae from Cerro Tololo, Chile. In fact, it was the first comet detected by this survey. The comet had an outburst shortly after discovery and has been getting brighter, and – if you have a small telescope or good binoculars – you can start watching it now. During most of September, Comet C/2017 O1 is in front of the constellation of Taurus and shows a brightness or magnitude of 9.5.

An orbit analysis of this celestial visitor indicates it will be at perihelion, or closest to the sun, on October 14, 2017. It’ll be closest to Earth on October 18, passing distantly at about 67 million miles (108 million km) from our planet.

Comet C/2017 O1 (ASASSN1) discovery image on July 19, 2017 plus 2 more dates. The comet was at a faint magnitude +15.3 at discovery. It quickly jumped 100 times in brightness – via an outburst – to magnitude +10. In October, it’s hoped the comet will be around magnitude 8, within reach of binoculars and small telescopes. Image via Benjamin Shappee/ Wikimedia Commons.

Although comets are unpredictable, recent observations show that C2017 O1 has brightened. It is not expected to become visible to the unaided eye, but the comet may reach a magnitude of around 8. If so, it’ll be well within reach of binoculars and small telescopes.

Binoculars should reveal it as a small fuzzy patch of light in the sky. Some observers may see a hint of green color in the comet, which is caused by gases like diatomic carbon.

Late on the night of Saturday, September 16, the comet was located below the familiar stars of the Pleiades cluster, a group of stars visible to the naked eye to the east shortly after midnight, as seen from central US.

Late on the night of Saturday, September 30, comet C/2017 O1 is located between the bright star Capella, in Auriga, and the Pleiades star cluster, as seen from central US. Illustration by Eddie Irizarry using Stellarium.

Location of comet C/2017 O1 during closest approach to Earth on October 18, 2017, as seen from central U.S., facing northeast. Illustration by Eddie Irizarry using Stellarium.

On the night of October 28, 2017 , comet C/2017 O1 passes close to star alpha Cam (HIP 22783), the brightest star of the constellation Camelopardalis. This 4th magnitude star is barely visible to the unaided eye. Illustration by Eddie Irizarry using Stellarium.

Although comet C/2017 O1 should be dimmer by December 1, 2017 , during the last month of this year the celestial visitor will be located close to Polaris, the north star. Illustration by Eddie Irizarry using Stellarium.

Also, see the comet’s page at TheSkyLive.

Bottom line: Charts that can help you find long-period comet C/2017 O1 (ASASSN1).



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Lake Louise

Lake Louise is a glacial lake within Banff National Park in Alberta, Canada. Manish Mamtani captured this image on September 5, 2017 . He wrote:

The smoke from a wildfire created a great mood. I used NiSi Filters to show the movement in the clouds and cut through the reflection in the foreground to show the rocks.

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

Donate to EarthSky: Your support means the world to us



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Lake Louise is a glacial lake within Banff National Park in Alberta, Canada. Manish Mamtani captured this image on September 5, 2017 . He wrote:

The smoke from a wildfire created a great mood. I used NiSi Filters to show the movement in the clouds and cut through the reflection in the foreground to show the rocks.

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

Donate to EarthSky: Your support means the world to us



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Occultations galore on September 18

Above photo: Lunar occultation of Venus by Ravindra Aradhya on February 26, 2014

Tomorrow – September 18, 2017 – the moon will occult three planets (Venus, Mars and Mercury) and one first-magnitude star (Regulus) in less than 24-hours time. This will be the first time since March 5, 2008, that three planets have been occulted by the moon in less than one day. The next time won’t be until July 24, 2036. Overall, this string of planetary occultations may be more of an academic than observational interest, because much of the world is not particularly well-situated for watching even one of these four occultations.

But don’t let that stop you from waking up early – say 90 to 60 minutes before sunrise – to get an eyeful of the moon, morning planets and Regulus all lining up in your eastern sky. We give you fair warning. Only the moon and Venus will be easy to spot in the predawn/dawn sky, though it shouldn’t be all that difficult to spot Regulus a short hop below Venus before dawn. It’ll take a more deliberate effort to catch Mercury and Mars near the horizon as the predawn darkness is giving way to morning twilight.

You’ll almost certainly need binoculars to see Mars – and possibly Mercury.

Click here for recommended almanacs; they can give you the rising times of the sun, moon, planets ainto your sky.

This chart is specifically for North American mid-northern latitudes. From the world’s Eastern Hemisphere, look for the moon on to be offset toward Venus and Regulus before sunrise September 18. The occultations of Venus and Regulus will have already passed by the time the moon and planets enter into the North American morning sky on September 18, 2017.

On September 18, the moon will occult Venus first (1 UTC), the star Regulus next (5 UTC), then Mars (20 UTC) and finally Mercury (23 UTC). To see any one of these occultations, however, you have to be at just the right spot on Earth. Even at that, the occultations of Regulus, Mars and Mercury will be extremely hard to observe because they occur in a daytime sky. Undoubtedly, you’ll need a telescope to see any of one these lunar occultations – that is, if any one of them even takes place in your sky.

A partial glance of the 2017 occultations via Guy Ottewell’s Astronomical Calendar 2017. Note that all four occultations on September 18, 2017 take place in a daytime sky.

Although the occultation of Venus happens during the daylight hours, as well, sharp-eyed observers can actually see the moon and Venus at daytime with no optical aid. We’re expecting some of our friends in the Southern Hemisphere – Indonesia, Australia and New Zealand – to see this occultation in their daytime sky on September 18. Remember, if you can see the moon – but not Venus – in the daytime sky, aim binoculars at the moon to spot nearby Venus in the same binocular field. Click here to find out the occultation times for numerous localities in Indonesia, Australia and New Zealand in Universal Time. Here’s how to convert Universal Time to local time.

Worldwide map via IOTA. Everyplace in between the dotted red lines sees the lunar occultatation of Venus in a daytime sky. Click here for more information.

Use the waning crescent moon and the dazzling planet Venus, the brightest and second-brightest heavenly bodies of nighttime, respectively, to seek out the grand alignment of the moon, planets and Regulus in your eastern sky some 90 to 60 minutes before sunrise. Good luck!



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Above photo: Lunar occultation of Venus by Ravindra Aradhya on February 26, 2014

Tomorrow – September 18, 2017 – the moon will occult three planets (Venus, Mars and Mercury) and one first-magnitude star (Regulus) in less than 24-hours time. This will be the first time since March 5, 2008, that three planets have been occulted by the moon in less than one day. The next time won’t be until July 24, 2036. Overall, this string of planetary occultations may be more of an academic than observational interest, because much of the world is not particularly well-situated for watching even one of these four occultations.

But don’t let that stop you from waking up early – say 90 to 60 minutes before sunrise – to get an eyeful of the moon, morning planets and Regulus all lining up in your eastern sky. We give you fair warning. Only the moon and Venus will be easy to spot in the predawn/dawn sky, though it shouldn’t be all that difficult to spot Regulus a short hop below Venus before dawn. It’ll take a more deliberate effort to catch Mercury and Mars near the horizon as the predawn darkness is giving way to morning twilight.

You’ll almost certainly need binoculars to see Mars – and possibly Mercury.

Click here for recommended almanacs; they can give you the rising times of the sun, moon, planets ainto your sky.

This chart is specifically for North American mid-northern latitudes. From the world’s Eastern Hemisphere, look for the moon on to be offset toward Venus and Regulus before sunrise September 18. The occultations of Venus and Regulus will have already passed by the time the moon and planets enter into the North American morning sky on September 18, 2017.

On September 18, the moon will occult Venus first (1 UTC), the star Regulus next (5 UTC), then Mars (20 UTC) and finally Mercury (23 UTC). To see any one of these occultations, however, you have to be at just the right spot on Earth. Even at that, the occultations of Regulus, Mars and Mercury will be extremely hard to observe because they occur in a daytime sky. Undoubtedly, you’ll need a telescope to see any of one these lunar occultations – that is, if any one of them even takes place in your sky.

A partial glance of the 2017 occultations via Guy Ottewell’s Astronomical Calendar 2017. Note that all four occultations on September 18, 2017 take place in a daytime sky.

Although the occultation of Venus happens during the daylight hours, as well, sharp-eyed observers can actually see the moon and Venus at daytime with no optical aid. We’re expecting some of our friends in the Southern Hemisphere – Indonesia, Australia and New Zealand – to see this occultation in their daytime sky on September 18. Remember, if you can see the moon – but not Venus – in the daytime sky, aim binoculars at the moon to spot nearby Venus in the same binocular field. Click here to find out the occultation times for numerous localities in Indonesia, Australia and New Zealand in Universal Time. Here’s how to convert Universal Time to local time.

Worldwide map via IOTA. Everyplace in between the dotted red lines sees the lunar occultatation of Venus in a daytime sky. Click here for more information.

Use the waning crescent moon and the dazzling planet Venus, the brightest and second-brightest heavenly bodies of nighttime, respectively, to seek out the grand alignment of the moon, planets and Regulus in your eastern sky some 90 to 60 minutes before sunrise. Good luck!



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2017 SkS Weekly Climate Change & Global Warming News Roundup #37

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Asia's glaciers to shrink by a third by 2100, threatening water supply of millions

High mountains of Asia hold biggest store of frozen water outside the poles and feed many of the world’s great rivers, including the Ganges

Asian Mountains The Asian high mountains are already warming more rapidly than the global average. Photograph: Alamy Stock Photo

Asia’s mountain glaciers will lose at least a third of their mass through global warming by the century’s end, with dire consequences for millions of people who rely on them for fresh water, researchers have said.

This is a best-case scenario, based on the assumption that the world manages to limit average global warming to 1.5C (2.7F) over pre-industrial levels, a team wrote in the journal Nature.

“To meet the 1.5C target will be a task of unprecedented difficulty,” the researchers said, “and even then, 36% (give or take 7%) of the ice mass in the high mountains of Asia is projected to be lost” by 2100.

With warming of 3.5C, 4C and 6C respectively, Asian glacier losses could amount to 49%, 51% or 65% by the end of the century, according to the team’s modelling study. 

Asia's glaciers to shrink by a third by 2100, threatening water supply of millions, Agence France-Presse/Guardian, Sep 13, 2017 

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from Skeptical Science http://ift.tt/2yf9KNk
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Asia's glaciers to shrink by a third by 2100, threatening water supply of millions

High mountains of Asia hold biggest store of frozen water outside the poles and feed many of the world’s great rivers, including the Ganges

Asian Mountains The Asian high mountains are already warming more rapidly than the global average. Photograph: Alamy Stock Photo

Asia’s mountain glaciers will lose at least a third of their mass through global warming by the century’s end, with dire consequences for millions of people who rely on them for fresh water, researchers have said.

This is a best-case scenario, based on the assumption that the world manages to limit average global warming to 1.5C (2.7F) over pre-industrial levels, a team wrote in the journal Nature.

“To meet the 1.5C target will be a task of unprecedented difficulty,” the researchers said, “and even then, 36% (give or take 7%) of the ice mass in the high mountains of Asia is projected to be lost” by 2100.

With warming of 3.5C, 4C and 6C respectively, Asian glacier losses could amount to 49%, 51% or 65% by the end of the century, according to the team’s modelling study. 

Asia's glaciers to shrink by a third by 2100, threatening water supply of millions, Agence France-Presse/Guardian, Sep 13, 2017 

Links posted on Facebook

Sun Sep 10, 2017

Mon Sep 11, 2017

Tue Sep 13, 2017

Wed Sep 14, 2017

Thu Sep 15, 2017

Fri Sep 16, 2017

Sat Sep 17, 2017



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