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Moon near Neptune on November 26

Tonight and tomorrow night – November 26 and 27, 2017 – the moon is sweeping near the 8th planet Neptune on the sky’s dome. It’s even harder than usual right now to find Neptune because of the moon’s glare. Still, if you want to know Neptune’s location on the sky’s dome – maybe in order to find it when the moon has moved away – look at tonight’s moon. It is pointing the way.

What will you see? Only the moon shining in all its splendor. You can gaze at it and imagine Neptune nearby.

The image below is a spacecraft image of Neptune. It’s from Voyager 2, the only spacecraft that has ever visited Neptune. The spacecraft’s closest approach to the planet occurred on August 25, 1989. Neptune is the eighth planet out from our sun and outermost of the major planets.

It’s the only major planet in our solar system that you absolutely can’t see with the unaided eye.

Photo of Neptune taken by Voyager 2 spacecraft in August 1989.

Like the moon, Neptune is close to the ecliptic, or path the planets follow in front of the constellations of the zodiac. We see them travel on or near this great circle on the celestial sphere because the major planets in our solar system, and Earth’s moon, orbit the sun on almost the same plane.

Although the moon and Neptune are close together on the sky’s dome tonight, they’re nowhere close in space. The moon resides just over one light-second from Earth, whereas Neptune looms way out there at over four light-hours away. In other words, Neptune is over 11,000 times farther away than the moon in tonight’s sky.

Once the moon leaves the evening sky, starting the second week of December, Aquarius will easy to spot in a dark country sky. Then, if you’re armed with a telescope or powerful binoculars and a good sky chart, you might be able to glimpse Neptune.

Neptune moves around the sun slowly in contrast to Earth. It takes 165 Earth-years to travel around the sun once, and thus it takes 165 years to travel completely around our sky. That means that Neptune has been hanging out more or less in the same location in our sky – in front of the constellation Aquarius, and near the star Lambda Aquarii – for a few years.

Sky chart of the constellation Aquarius, We label the star Lambda Aquarii, a 4th-magnitude star that is visible to the unaided eye in a dark sky.

Sky chart of the constellation Aquarius, We label the star Lambda Aquarii, a 4th-magnitude star that is visible to the unaided eye in a dark sky.

For a stellar reference, learn how to star-hop to Lambda Aquarii, your guide star to Neptune. Neptune demands high-quality binoculars or a telescope, patience and a detailed star chart. Look for Neptune and the star Lambda Aquarii to take stage within the same binocular field.

Bottom line: On November 26, 2017, use your mind’s eye to envision the solar system’s most distant major planet – Neptune – near the moon.

Do you love stargazing? Order your EarthSky Planisphere today!



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Tonight and tomorrow night – November 26 and 27, 2017 – the moon is sweeping near the 8th planet Neptune on the sky’s dome. It’s even harder than usual right now to find Neptune because of the moon’s glare. Still, if you want to know Neptune’s location on the sky’s dome – maybe in order to find it when the moon has moved away – look at tonight’s moon. It is pointing the way.

What will you see? Only the moon shining in all its splendor. You can gaze at it and imagine Neptune nearby.

The image below is a spacecraft image of Neptune. It’s from Voyager 2, the only spacecraft that has ever visited Neptune. The spacecraft’s closest approach to the planet occurred on August 25, 1989. Neptune is the eighth planet out from our sun and outermost of the major planets.

It’s the only major planet in our solar system that you absolutely can’t see with the unaided eye.

Photo of Neptune taken by Voyager 2 spacecraft in August 1989.

Like the moon, Neptune is close to the ecliptic, or path the planets follow in front of the constellations of the zodiac. We see them travel on or near this great circle on the celestial sphere because the major planets in our solar system, and Earth’s moon, orbit the sun on almost the same plane.

Although the moon and Neptune are close together on the sky’s dome tonight, they’re nowhere close in space. The moon resides just over one light-second from Earth, whereas Neptune looms way out there at over four light-hours away. In other words, Neptune is over 11,000 times farther away than the moon in tonight’s sky.

Once the moon leaves the evening sky, starting the second week of December, Aquarius will easy to spot in a dark country sky. Then, if you’re armed with a telescope or powerful binoculars and a good sky chart, you might be able to glimpse Neptune.

Neptune moves around the sun slowly in contrast to Earth. It takes 165 Earth-years to travel around the sun once, and thus it takes 165 years to travel completely around our sky. That means that Neptune has been hanging out more or less in the same location in our sky – in front of the constellation Aquarius, and near the star Lambda Aquarii – for a few years.

Sky chart of the constellation Aquarius, We label the star Lambda Aquarii, a 4th-magnitude star that is visible to the unaided eye in a dark sky.

Sky chart of the constellation Aquarius, We label the star Lambda Aquarii, a 4th-magnitude star that is visible to the unaided eye in a dark sky.

For a stellar reference, learn how to star-hop to Lambda Aquarii, your guide star to Neptune. Neptune demands high-quality binoculars or a telescope, patience and a detailed star chart. Look for Neptune and the star Lambda Aquarii to take stage within the same binocular field.

Bottom line: On November 26, 2017, use your mind’s eye to envision the solar system’s most distant major planet – Neptune – near the moon.

Do you love stargazing? Order your EarthSky Planisphere today!



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2017 SkS Weekly Climate Change & Global Warming News Roundup #47

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

Editor's Pick

Should a healthy environment be a human right? These Norwegians think so 

Norwegians Portest Arctic Drilling 

Greenpeace and the environmental group Youth and Nature are suing the Norwegian Government for granting Arctic oil drilling licenses.

Their argument is based on an article in the Norwegian constitution protecting the right to an environment that’s healthy and that long-term consideration be given to digging up natural resources.

Greenpeace Norway head Truls Gulowsen told Hack it all comes down to climate change and oil licenses.

"We had challenged the Norwegian state for handing out new licenses for drilling in the arctic in spite of the fact that they have signed the Paris Agreement," he said on his way to court.

"They acknowledge climate change is a problem, and they know that the world has already found more carbon, fossil carbon, than we can ever afford to burn."

He said Norway's constitution gives future generations the right to a healthy environment.

"[That] puts duties on the state to guarantee and safeguard those rights."

Brendan Sydes, lawyer and CEO of Environmental Justice Australia, says the strategy used by Greenpeace goes to a country’s legal foundation, instead of working with a country's environmental regulations.

Should a healthy environment be a human right? These Norwegians think so by Courtney Carthy, ABC News (Australia), Nov 23, 2017

Links posted on Facebook

Sun Nov 19, 2017

Mon Nov 20, 2017

Tue Nov 21, 2017

Wed Nov 22, 2017

Thu Nov 23, 2017

Fri Nov 24, 2017

Sat Nov 25, 2017



from Skeptical Science http://ift.tt/2zDxUp7
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Should a healthy environment be a human right? These Norwegians think so 

Norwegians Portest Arctic Drilling 

Greenpeace and the environmental group Youth and Nature are suing the Norwegian Government for granting Arctic oil drilling licenses.

Their argument is based on an article in the Norwegian constitution protecting the right to an environment that’s healthy and that long-term consideration be given to digging up natural resources.

Greenpeace Norway head Truls Gulowsen told Hack it all comes down to climate change and oil licenses.

"We had challenged the Norwegian state for handing out new licenses for drilling in the arctic in spite of the fact that they have signed the Paris Agreement," he said on his way to court.

"They acknowledge climate change is a problem, and they know that the world has already found more carbon, fossil carbon, than we can ever afford to burn."

He said Norway's constitution gives future generations the right to a healthy environment.

"[That] puts duties on the state to guarantee and safeguard those rights."

Brendan Sydes, lawyer and CEO of Environmental Justice Australia, says the strategy used by Greenpeace goes to a country’s legal foundation, instead of working with a country's environmental regulations.

Should a healthy environment be a human right? These Norwegians think so by Courtney Carthy, ABC News (Australia), Nov 23, 2017

Links posted on Facebook

Sun Nov 19, 2017

Mon Nov 20, 2017

Tue Nov 21, 2017

Wed Nov 22, 2017

Thu Nov 23, 2017

Fri Nov 24, 2017

Sat Nov 25, 2017



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Star of the week: Hamal

These are star trails, and one of the brightest trails here is Alpha Arietis, or Hamal. To learn which one, click here, then click on the image you find. This neat image is by Herb Raab on Flickr.

These are star trails, and one of the brightest trails here is Alpha Arietis, or Hamal. To learn which one, click here, then click on the image you find. This neat image is via Herb Raab on Flickr.

Hamal – also known as Alpha Arietis – shines as the brightest star in the constellation Aries the Ram. This star and two others – Sheratan and Mesarthim – make up the Head of the Ram. Aries is small. But the compact pattern of these three stars makes Aries relatively easy to find. As seen from mid-northern latitudes, Hamal lights up the eastern sky on autumn evenings, shines high in the southern sky on winter evenings, and sits in the west on early spring evenings. Hamal disappears from the night sky in April, then returns to the eastern sky before sunrise by late spring or early summer, to begin another cycle of visibility.

It’s fun to spot Hamal and its brother stars in the night sky. But this star also has a profound significance in the history of astronomy.

Most people see the constellation Aries as three stars in a compact grouping. The stars are Hamal, Sheratan, and Mesarthim.

If you could see the stars in daytime, you’d see the sun and Hamal in conjunction (lined up with one another, due north and south in right ascension) on or near April 24. What this means is that – when the sun appears due south at noon – Hamal is due south, too, though lost in the glare of the noonday sun.

April 24 – the date of Hamal’s conjunction with the sun – is a little more than one month after the March equinox, which always takes place around March 20. This is the Northern Hemisphere’s spring equinox, and it’s a time of renewal throughout the northern half of Earth. So of course this time of year had significance to our ancestors, who were much more aware than we are of their dependence on the land and sky.

What is the relationship of Hamal to the March equinox? If you could backtrack some 2,500 years, you’d find the annual conjunction of the sun and Hamal happening on the March equinox. In fact, if you could backtrack 2,200 years, we’d find the March equinox sun in conjunction with the star Sheratan. So you see that the location of the sun at the March equinox sun drifts in front of the stars. It moves westward in front of the backdrop constellations by about one degree (two sun diameters) every 72 years. This drifting is due to a well-known motion of Earth called precession, or sometimes the precession of the equinoxes.

The March equinox sun shone in front of the constellation Aries from about 2,000 to 100 BCE. At present, the sun shines in front of the constellation Pisces on the March equinox. Even so, many people pay homage to the Ram and still refer to the March equinox point as the First Point of Aries.

Bottom line: The star Hamal, also known as Alpha Arietis, is the brightest star in Aries the Ram. Thousands of years ago, the sun was in conjunction – or aligned north and south – with this star at the time of the March equinox. Nowadays, we see the sun in front of Pisces at the time of the March equinox. But people still refer to the sun’s location at the equinox as the First Point in Aries.

Sky chart of the constellation Aries the Ram

Nowadays the sun passes in front of the constellation Aries from about April 19 to May 13. Click here for a larger chart

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



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These are star trails, and one of the brightest trails here is Alpha Arietis, or Hamal. To learn which one, click here, then click on the image you find. This neat image is by Herb Raab on Flickr.

These are star trails, and one of the brightest trails here is Alpha Arietis, or Hamal. To learn which one, click here, then click on the image you find. This neat image is via Herb Raab on Flickr.

Hamal – also known as Alpha Arietis – shines as the brightest star in the constellation Aries the Ram. This star and two others – Sheratan and Mesarthim – make up the Head of the Ram. Aries is small. But the compact pattern of these three stars makes Aries relatively easy to find. As seen from mid-northern latitudes, Hamal lights up the eastern sky on autumn evenings, shines high in the southern sky on winter evenings, and sits in the west on early spring evenings. Hamal disappears from the night sky in April, then returns to the eastern sky before sunrise by late spring or early summer, to begin another cycle of visibility.

It’s fun to spot Hamal and its brother stars in the night sky. But this star also has a profound significance in the history of astronomy.

Most people see the constellation Aries as three stars in a compact grouping. The stars are Hamal, Sheratan, and Mesarthim.

If you could see the stars in daytime, you’d see the sun and Hamal in conjunction (lined up with one another, due north and south in right ascension) on or near April 24. What this means is that – when the sun appears due south at noon – Hamal is due south, too, though lost in the glare of the noonday sun.

April 24 – the date of Hamal’s conjunction with the sun – is a little more than one month after the March equinox, which always takes place around March 20. This is the Northern Hemisphere’s spring equinox, and it’s a time of renewal throughout the northern half of Earth. So of course this time of year had significance to our ancestors, who were much more aware than we are of their dependence on the land and sky.

What is the relationship of Hamal to the March equinox? If you could backtrack some 2,500 years, you’d find the annual conjunction of the sun and Hamal happening on the March equinox. In fact, if you could backtrack 2,200 years, we’d find the March equinox sun in conjunction with the star Sheratan. So you see that the location of the sun at the March equinox sun drifts in front of the stars. It moves westward in front of the backdrop constellations by about one degree (two sun diameters) every 72 years. This drifting is due to a well-known motion of Earth called precession, or sometimes the precession of the equinoxes.

The March equinox sun shone in front of the constellation Aries from about 2,000 to 100 BCE. At present, the sun shines in front of the constellation Pisces on the March equinox. Even so, many people pay homage to the Ram and still refer to the March equinox point as the First Point of Aries.

Bottom line: The star Hamal, also known as Alpha Arietis, is the brightest star in Aries the Ram. Thousands of years ago, the sun was in conjunction – or aligned north and south – with this star at the time of the March equinox. Nowadays, we see the sun in front of Pisces at the time of the March equinox. But people still refer to the sun’s location at the equinox as the First Point in Aries.

Sky chart of the constellation Aries the Ram

Nowadays the sun passes in front of the constellation Aries from about April 19 to May 13. Click here for a larger chart

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



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Waving hi to ISS

Photo from Karthik Easvur.

The International Space Station (ISS) orbits at approximately 220 miles (350 km) above the Earth and it travels at an average speed of 17,227 miles (27,724 km) per hour. The ISS makes multiple orbits around the Earth every day. To us on Earth, the space station looks like a bright star moving quickly above the horizon. Then, just as suddenly as it appears, it disappears. Karthik Easvur in Hyderabad, India caught it on November 22, 2017.

ISS will likely pass over your location every so often. Click here to learn how you can see ISS, as it soars overhead in your sky.

This month marks 17 years of humans living and working continuously aboard ISS. The current crew – Expedition 53 – began in September 2017 and ends next month. It consists of six crew members, whose official portrait is below.

Visit the Expedition 53 mission page

Here’s who’s aboard ISS now. This official crew portrait of Expedition 53 was taken June 20, 2017 at Johnson Space Center in Houston, Texas. Seated in the front (from left) are Flight Engineer Alexander Misurkin of Roscosmos and Commander Randy Bresnik of NASA. Standing in the back (from left) are NASA astronauts Joe Acaba and Mark Vande Hei, Sergey Ryazanskiy of Roscosmos and Paolo Nespoli of the European Space Agency. Image via NASA Johnson on Flickr.

NASA astronaut and ISS flight engineer Randy Bresnik takes photos of Earth from the Cupola window. Image via NASA.

Bottom line: Waving to the International Space Station on November 22, 2017 from Hyderabad, India.



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Photo from Karthik Easvur.

The International Space Station (ISS) orbits at approximately 220 miles (350 km) above the Earth and it travels at an average speed of 17,227 miles (27,724 km) per hour. The ISS makes multiple orbits around the Earth every day. To us on Earth, the space station looks like a bright star moving quickly above the horizon. Then, just as suddenly as it appears, it disappears. Karthik Easvur in Hyderabad, India caught it on November 22, 2017.

ISS will likely pass over your location every so often. Click here to learn how you can see ISS, as it soars overhead in your sky.

This month marks 17 years of humans living and working continuously aboard ISS. The current crew – Expedition 53 – began in September 2017 and ends next month. It consists of six crew members, whose official portrait is below.

Visit the Expedition 53 mission page

Here’s who’s aboard ISS now. This official crew portrait of Expedition 53 was taken June 20, 2017 at Johnson Space Center in Houston, Texas. Seated in the front (from left) are Flight Engineer Alexander Misurkin of Roscosmos and Commander Randy Bresnik of NASA. Standing in the back (from left) are NASA astronauts Joe Acaba and Mark Vande Hei, Sergey Ryazanskiy of Roscosmos and Paolo Nespoli of the European Space Agency. Image via NASA Johnson on Flickr.

NASA astronaut and ISS flight engineer Randy Bresnik takes photos of Earth from the Cupola window. Image via NASA.

Bottom line: Waving to the International Space Station on November 22, 2017 from Hyderabad, India.



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News digest – NHS announcements, the Budget, experimental treatments and… alcoholic jelly?

  • A series of NHS announcements hit the news this week, starting off with new commitments to diagnosing cancer earlier. Our blog post and The Telegraph cover the new plans, which include a renewed pledge for a new bowel screening test and extended pilots of car park CT scans for those at high risk of lung cancer.
  • Next up was the eagerly-anticipated Budget, in which the Chancellor promised the NHS £350 million for the coming winter, followed by injection of £1.6 billion next year. But as the BBC and Guardian reported, experts have warned that this commitment falls far short of what’s needed for the country’s healthcare demands.
  • Elsewhere in the Budget, Chancellor Philip Hammond showcased the UK’s commitment to keeping at the forefront of research, announcing a significant boost to research investment over the next four years. BBC News has more on this one.
  • The Daily Mail and Express reported on an experimental immunotherapy that’s reportedly being developed in mice at King’s College London. The news wasn’t tied to any published research, but said the approach would involve giving patients a particular type of immune cell sourced from blood banks and boosted in the lab. It’s a long way from the talk of cures that featured in many headlines.
  • An experimental treatment for patients with head and neck cancers will soon be tested in patients in a trial coordinated by our Clinical Trials Unit in Birmingham. Lab studies have shown the drug can boost the effectiveness of certain chemotherapy drugs and radiotherapy, so the study is seeing how it works in combination with these treatments. Our press release has more.
  • Post-traumatic stress disorder (PTSD) could be common among cancer patients, research from Malaysia suggests. According to the work, 1 in 5 patients could experience the condition, and around a third still had PTSD four years after diagnosis. BBC News covered the study.
  • Public awareness of the link between obesity and cancer is worryingly low in the UK, according to our recently published research picked up by PharmaTimes. Being overweight or obese increases the risk of 13 types of cancer, but this study found that only 1 in 4 people who completed a survey identified this as a risk factor.
  • More on the subject, unpublished Swedish research covered by the BBC and Mail Online found that breast tumours picked up during or between mammograms in overweight or obese women tend to be large. But as we told the BBC, it’s not clear whether women with a high BMI could benefit from more frequent breast screening in the UK.
  • Smoking causes at least 14 types of cancer, but it’s still unclear whether smoking also causes breast cancer. A new study found that the risk of this disease is 14% higher in women who have ever smoked, with the risk increasing the longer you smoke for. But this relationship wasn’t found in those who’d never drunk alcohol, so it’s difficult to untangle the potential overlap between these two factors. Forbes has the details.
  • A report from Macmillan Cancer Support found that people in the poorest areas of London aren’t getting the same standard of cancer care as the rest of England. The results, covered by BBC News, also showed black, Asian and ethnic minority patients had worse care than white people in London.
  • The decision on whether the NHS should fund an effective hormone therapy as an upfront treatment for some men with prostate cancer won’t happen until autumn next year, the Telegraph reports. This news follows on from an earlier declaration this week by the European Medicines Agency that the drug is safe.
  • Bacteria found in certain bowel cancers can also be found inside a small number of tumours that have spread to another part of the body, says new research. We covered the study, which also showed the bacteria helped bowel cancer cells grow in mice.

And finally

  • Not quite vodka jelly, but scientists are working on mixing alcohol (ethanol, to be precise) into a jelly-like substance as a potential treatment for cancer, reports the Mail Online. Scientists have already used ethanol as a treatment for some cancers, which involves injecting the alcohol into tumours to kill the cancer cells. But the researchers hope that by making it more gelatinous, the treatment could become more effective by preventing it from leaking out from the tumour. But it’s early stage research that hasn’t left the lab, so we don’t yet know if it’ll be safe or effective in people.

Justine 



from Cancer Research UK – Science blog http://ift.tt/2Aw7BkI
  • A series of NHS announcements hit the news this week, starting off with new commitments to diagnosing cancer earlier. Our blog post and The Telegraph cover the new plans, which include a renewed pledge for a new bowel screening test and extended pilots of car park CT scans for those at high risk of lung cancer.
  • Next up was the eagerly-anticipated Budget, in which the Chancellor promised the NHS £350 million for the coming winter, followed by injection of £1.6 billion next year. But as the BBC and Guardian reported, experts have warned that this commitment falls far short of what’s needed for the country’s healthcare demands.
  • Elsewhere in the Budget, Chancellor Philip Hammond showcased the UK’s commitment to keeping at the forefront of research, announcing a significant boost to research investment over the next four years. BBC News has more on this one.
  • The Daily Mail and Express reported on an experimental immunotherapy that’s reportedly being developed in mice at King’s College London. The news wasn’t tied to any published research, but said the approach would involve giving patients a particular type of immune cell sourced from blood banks and boosted in the lab. It’s a long way from the talk of cures that featured in many headlines.
  • An experimental treatment for patients with head and neck cancers will soon be tested in patients in a trial coordinated by our Clinical Trials Unit in Birmingham. Lab studies have shown the drug can boost the effectiveness of certain chemotherapy drugs and radiotherapy, so the study is seeing how it works in combination with these treatments. Our press release has more.
  • Post-traumatic stress disorder (PTSD) could be common among cancer patients, research from Malaysia suggests. According to the work, 1 in 5 patients could experience the condition, and around a third still had PTSD four years after diagnosis. BBC News covered the study.
  • Public awareness of the link between obesity and cancer is worryingly low in the UK, according to our recently published research picked up by PharmaTimes. Being overweight or obese increases the risk of 13 types of cancer, but this study found that only 1 in 4 people who completed a survey identified this as a risk factor.
  • More on the subject, unpublished Swedish research covered by the BBC and Mail Online found that breast tumours picked up during or between mammograms in overweight or obese women tend to be large. But as we told the BBC, it’s not clear whether women with a high BMI could benefit from more frequent breast screening in the UK.
  • Smoking causes at least 14 types of cancer, but it’s still unclear whether smoking also causes breast cancer. A new study found that the risk of this disease is 14% higher in women who have ever smoked, with the risk increasing the longer you smoke for. But this relationship wasn’t found in those who’d never drunk alcohol, so it’s difficult to untangle the potential overlap between these two factors. Forbes has the details.
  • A report from Macmillan Cancer Support found that people in the poorest areas of London aren’t getting the same standard of cancer care as the rest of England. The results, covered by BBC News, also showed black, Asian and ethnic minority patients had worse care than white people in London.
  • The decision on whether the NHS should fund an effective hormone therapy as an upfront treatment for some men with prostate cancer won’t happen until autumn next year, the Telegraph reports. This news follows on from an earlier declaration this week by the European Medicines Agency that the drug is safe.
  • Bacteria found in certain bowel cancers can also be found inside a small number of tumours that have spread to another part of the body, says new research. We covered the study, which also showed the bacteria helped bowel cancer cells grow in mice.

And finally

  • Not quite vodka jelly, but scientists are working on mixing alcohol (ethanol, to be precise) into a jelly-like substance as a potential treatment for cancer, reports the Mail Online. Scientists have already used ethanol as a treatment for some cancers, which involves injecting the alcohol into tumours to kill the cancer cells. But the researchers hope that by making it more gelatinous, the treatment could become more effective by preventing it from leaking out from the tumour. But it’s early stage research that hasn’t left the lab, so we don’t yet know if it’ll be safe or effective in people.

Justine 



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Orion the Hunter now easy to view

Tonight, watch for Orion the Hunter – perhaps the easiest-to-identify of all constellations – rising at mid-evening. It’s around late November and early December that people begin to notice Orion in the evening sky, and to comment on it. Orion will climb over your eastern horizon by around 9 p.m. tonight. You can find this constellation and watch it for months to come.

The most noticeable part of Orion is the pattern called Orion’s Belt: three medium-bright stars in a short, straight row. As seen from mid-northern latitudes, Orion appears to be lying on his side – with his Belt stars pointing upward – when he first ascends into our eastern sky in mid-evening at this time of year. Orion’s two brightest stars — Betelgeuse and Rigel — shine on opposite sides of the Belt.

Stars trails of constellation Orion via EarthSky Facebook friend Jean Baptiste Feldman. Can you pick out the three stars in Orion’s Belt? Notice also the different colors of the stars in Orion.

As night passes, and Earth spins beneath the sky, Orion will climb higher in our sky. When this constellation is highest in the south, it is a huge, noticeable star pattern. But Orion doesn’t reach its highest point until an hour or two after midnight (that’s local time, for all times zones around the world) at this time of year.

Like all the stars, Orion’s stars rise some four minutes earlier with each passing day, or about two hours earlier with each passing month. If you see Orion shining in the east at 9:00 p.m. tonight, look for Orion to be in the same place in the sky at about 7:00 p.m. a month from now. Or if Orion is due south at 1:30 a.m. tomorrow, look for Orion to be due south at 11:30 p.m. in late December.

Almost gone! EarthSky lunar calendars make great gifts. Order now.

Mirror view of Orion the Hunter from Johannes Hevelius' Uranographia (1690)

This shift in Orion’s location is due to Earth’s movement in orbit around the sun. As we move around the sun, our perspective on the stars surrounding us shifts. At the same hour daily, all the stars in the eastern half of sky climb up a bit higher, whereas all the stars in the western half of sky sink a bit closer to the western horizon.

Are you familiar with the W- or M-shaped constellation Cassiopeia the Queen? Or Polaris, the North Star? As Orion rises in the east this evening, look for Cassiopeia to soar to her highest point for the night, above Polaris in the northern sky.

Karthik Easvur caught the constellation Orion on November 26, 2016, from his balcony in Hyderabad, India. The round translucent object in the photo, by the way, is a lens flare - an internal reflection from Karthik's camera - like caused by the same artificial light that's illuminating the palm tree on the right.

Karthik Easvur caught the constellation Orion on November 26, 2016, from his balcony in Hyderabad, India. The round translucent object in the photo, by the way, is a lens flare – an internal reflection from Karthik’s camera – likely caused by the same artificial light that’s illuminating the palm tree on the right.

Bottom line: The famous constellation Orion the Hunter is rising at mid-evening in late November and early December.

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Tonight, watch for Orion the Hunter – perhaps the easiest-to-identify of all constellations – rising at mid-evening. It’s around late November and early December that people begin to notice Orion in the evening sky, and to comment on it. Orion will climb over your eastern horizon by around 9 p.m. tonight. You can find this constellation and watch it for months to come.

The most noticeable part of Orion is the pattern called Orion’s Belt: three medium-bright stars in a short, straight row. As seen from mid-northern latitudes, Orion appears to be lying on his side – with his Belt stars pointing upward – when he first ascends into our eastern sky in mid-evening at this time of year. Orion’s two brightest stars — Betelgeuse and Rigel — shine on opposite sides of the Belt.

Stars trails of constellation Orion via EarthSky Facebook friend Jean Baptiste Feldman. Can you pick out the three stars in Orion’s Belt? Notice also the different colors of the stars in Orion.

As night passes, and Earth spins beneath the sky, Orion will climb higher in our sky. When this constellation is highest in the south, it is a huge, noticeable star pattern. But Orion doesn’t reach its highest point until an hour or two after midnight (that’s local time, for all times zones around the world) at this time of year.

Like all the stars, Orion’s stars rise some four minutes earlier with each passing day, or about two hours earlier with each passing month. If you see Orion shining in the east at 9:00 p.m. tonight, look for Orion to be in the same place in the sky at about 7:00 p.m. a month from now. Or if Orion is due south at 1:30 a.m. tomorrow, look for Orion to be due south at 11:30 p.m. in late December.

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Mirror view of Orion the Hunter from Johannes Hevelius' Uranographia (1690)

This shift in Orion’s location is due to Earth’s movement in orbit around the sun. As we move around the sun, our perspective on the stars surrounding us shifts. At the same hour daily, all the stars in the eastern half of sky climb up a bit higher, whereas all the stars in the western half of sky sink a bit closer to the western horizon.

Are you familiar with the W- or M-shaped constellation Cassiopeia the Queen? Or Polaris, the North Star? As Orion rises in the east this evening, look for Cassiopeia to soar to her highest point for the night, above Polaris in the northern sky.

Karthik Easvur caught the constellation Orion on November 26, 2016, from his balcony in Hyderabad, India. The round translucent object in the photo, by the way, is a lens flare - an internal reflection from Karthik's camera - like caused by the same artificial light that's illuminating the palm tree on the right.

Karthik Easvur caught the constellation Orion on November 26, 2016, from his balcony in Hyderabad, India. The round translucent object in the photo, by the way, is a lens flare – an internal reflection from Karthik’s camera – likely caused by the same artificial light that’s illuminating the palm tree on the right.

Bottom line: The famous constellation Orion the Hunter is rising at mid-evening in late November and early December.

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Our nights are brighter, and brighter

Astrophotographer Amit Kamble in New Zealand calls this image Save Me From Light. Read more about this image.

Of course, our night skies are more washed with artificial light than those of our ancestors, but apparently – despite the efforts of groups such as the International Dark-Sky Association (IDA) – Earth’s night skies are still getting brighter. A landmark study released November 22, 2017 found both light pollution – and energy consumption by lighting – steadily increasing. The study is based on five years of satellite images. The data show gains of two percent per year in the amount of the Earth’s surface that is artificially lit at night and in the quantity of light emitted. The study noted a correlation between some nations’ economic development and their brighter night skies. And it noted zero decline in rates of light pollution in already-developed nations, where a switch to energy-saving LEDs was thought by some to be helping to save the night.

Christopher Kyba of the GFZ German Research Center for Geosciences in Potsdam, Germany led the international team of scientists that conducted the study. It was published November 22 in the peer-reviewed journal Science Advances.

The team analyzed five years of images from the Suomi NPP satellite and said the saw increases in light pollution almost everywhere they looked. Some of the largest gains were in regions that had been previously unlit. Kyba noted in a statement at IDA’s website:

Light is growing most rapidly in places that didn’t have a lot of light to start with. That means that the fastest rates of increase are occurring in places that so far hadn’t been very strongly affected by light pollution.

View larger. | World maps showing the rates of change of the lit area of the world (l) and the measured brightness (r) of each country during 2012-2016. Warmer colors in each map correspond to higher rates of change. Image via Kyba et al. / Science Advances/ IDA.

The study is among the first to examine the effects, as seen from space, of the ongoing worldwide transition to LED lighting. LED lighting requires less electricity to yield the same quantity of light as older lighting technologies. Proponents of LED lighting have argued that the high energy efficiency of LEDs would contribute to slowing overall global energy demand, given that outdoor lighting accounts for a significant fraction of the nighttime energy budget of the typical world city. The team tested this idea:

… comparing changes in nighttime lighting seen from Earth orbit to changes in countries’ gross domestic product, or GDP – a measure of their overall economic output – during the same time period. They concluded that financial savings from the improved energy efficiency of outdoor lighting appear to be invested into the deployment of more lights. As a consequence, the expected large reductions in global energy consumption for outdoor lighting have not been realized.

Kyba said he expects the upward global trend in the use of outdoor lighting to continue, and, he believes, it will bring many negative environmental consequences:

There is a potential for the solid-state lighting revolution to save energy and reduce light pollution, but only if we don’t spend the savings on new light.

Outdoor lighting in Doha, Qatar, between 2012 (cyan) and 2016 (red) as seen from the Suomi satellite. Areas newly lit since 2012 appear in bright red. Image via Kyba et al. / Science Advances/ IDA.

IDA has campaigned for the last 30 years to bring attention to the known and suspected hazards associated with the use of artificial light at night. IDA Executive Director J. Scott Feierabend pointed out repercussions including harm to wildlife, threats to human wellbeing, and potentially compromised public safety. IDA drew public attention to concerns associated with the strong blue light emissions of LED lighting as early as 2010. Feierabend explained:

Today’s announcement validates the message IDA has communicated for years. We hope that the results further sound the alarm about the many unintended consequences of the unchecked use of artificial light at night.

Read more from the International Dark-Sky Association

Infographic showing the number of countries experiencing various rates of change of night lights during 2012-2016. Image via Kyba et al. / Science Advances/ IDA.

Bottom line: An international team of scientists conducted a landmark study showing that Earth’s night skies are brightening at a rate of 2 percent each year.

Source: Artificially lit surface of Earth at night increasing in radiance and extent



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Astrophotographer Amit Kamble in New Zealand calls this image Save Me From Light. Read more about this image.

Of course, our night skies are more washed with artificial light than those of our ancestors, but apparently – despite the efforts of groups such as the International Dark-Sky Association (IDA) – Earth’s night skies are still getting brighter. A landmark study released November 22, 2017 found both light pollution – and energy consumption by lighting – steadily increasing. The study is based on five years of satellite images. The data show gains of two percent per year in the amount of the Earth’s surface that is artificially lit at night and in the quantity of light emitted. The study noted a correlation between some nations’ economic development and their brighter night skies. And it noted zero decline in rates of light pollution in already-developed nations, where a switch to energy-saving LEDs was thought by some to be helping to save the night.

Christopher Kyba of the GFZ German Research Center for Geosciences in Potsdam, Germany led the international team of scientists that conducted the study. It was published November 22 in the peer-reviewed journal Science Advances.

The team analyzed five years of images from the Suomi NPP satellite and said the saw increases in light pollution almost everywhere they looked. Some of the largest gains were in regions that had been previously unlit. Kyba noted in a statement at IDA’s website:

Light is growing most rapidly in places that didn’t have a lot of light to start with. That means that the fastest rates of increase are occurring in places that so far hadn’t been very strongly affected by light pollution.

View larger. | World maps showing the rates of change of the lit area of the world (l) and the measured brightness (r) of each country during 2012-2016. Warmer colors in each map correspond to higher rates of change. Image via Kyba et al. / Science Advances/ IDA.

The study is among the first to examine the effects, as seen from space, of the ongoing worldwide transition to LED lighting. LED lighting requires less electricity to yield the same quantity of light as older lighting technologies. Proponents of LED lighting have argued that the high energy efficiency of LEDs would contribute to slowing overall global energy demand, given that outdoor lighting accounts for a significant fraction of the nighttime energy budget of the typical world city. The team tested this idea:

… comparing changes in nighttime lighting seen from Earth orbit to changes in countries’ gross domestic product, or GDP – a measure of their overall economic output – during the same time period. They concluded that financial savings from the improved energy efficiency of outdoor lighting appear to be invested into the deployment of more lights. As a consequence, the expected large reductions in global energy consumption for outdoor lighting have not been realized.

Kyba said he expects the upward global trend in the use of outdoor lighting to continue, and, he believes, it will bring many negative environmental consequences:

There is a potential for the solid-state lighting revolution to save energy and reduce light pollution, but only if we don’t spend the savings on new light.

Outdoor lighting in Doha, Qatar, between 2012 (cyan) and 2016 (red) as seen from the Suomi satellite. Areas newly lit since 2012 appear in bright red. Image via Kyba et al. / Science Advances/ IDA.

IDA has campaigned for the last 30 years to bring attention to the known and suspected hazards associated with the use of artificial light at night. IDA Executive Director J. Scott Feierabend pointed out repercussions including harm to wildlife, threats to human wellbeing, and potentially compromised public safety. IDA drew public attention to concerns associated with the strong blue light emissions of LED lighting as early as 2010. Feierabend explained:

Today’s announcement validates the message IDA has communicated for years. We hope that the results further sound the alarm about the many unintended consequences of the unchecked use of artificial light at night.

Read more from the International Dark-Sky Association

Infographic showing the number of countries experiencing various rates of change of night lights during 2012-2016. Image via Kyba et al. / Science Advances/ IDA.

Bottom line: An international team of scientists conducted a landmark study showing that Earth’s night skies are brightening at a rate of 2 percent each year.

Source: Artificially lit surface of Earth at night increasing in radiance and extent



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