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Hundreds of millions of South Asians at risk from glacier melt

A roadside market along the way from Kabul to Mazer-i-Sharif, Afghanistan. Hundreds of millions of people in countries near the Hindu Kush mountain range are at risk from glacial melt. Photo credit: Susan Novak/Flickr

A roadside market along the way from Kabul to Mazer-i-Sharif, Afghanistan. Hundreds of millions of people in countries near the Hindu Kush mountain range are at risk from glacial melt. Photo credit: Susan Novak/Flickr

Few regions on Earth depend as heavily on glaciers for food, energy and water as South Asia’s Hindu Kush Himalayan ecosystem. But now hundreds of millions in South Asia are at risk from glacier melt. A new research paper in the journal Environmental Science and Policy highlights some of the challenges downstream communities face when glacier water from upstream communities becomes scarce.

First-ever image of 5th order rainbow!

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Enhanced image of 5th order rainbow. Photo by Harald Edens.

The familiar primary and secondary rainbows have been known since there were eyes. The long sought 3rd and 4th order rainbows were finally imaged in 2011. Now we have the 5th order!

Comet Siding Spring’s near-miss of Mars was October 19

Comet Siding Spring closest to Mars on October 19, 2914.  Image via Virtual Telescope Project.  Read more about this image.

Comet Siding Spring closest to Mars on October 19, 2914. Image via Virtual Telescope Project.

The close pass of Comet Siding Spring to Mars was exciting! Closest approach was October 19. Watch for more photos from the event – both from earthly observers and from the spacecraft orbiting Mars and on Mars’ surface – here at EarthSky.org.

Why do trees shed their leaves in the fall?

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Autumn leaves. Image Credit: Tracy Ducasse.

Something to think about while raking …

Double Cluster in Perseus: Two star clusters

The Double Cluster is also known as h and Chi Persei. It resides in the northern part of the constellation Perseus, quite close to the constellation Cassiopeia the Queen. If you have a dark sky and find Cassiopeia – which is easy, because the constellation has a distinctive M or W shape – be sure to look for Perseus, too. Then just scan with your binoculars between them. The Double Cluster – a breathtaking pair of clusters, each containing supergiant suns – will be there. Follow the links inside to learn more.

Found Cassiopeia? Now look for Perseus

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If you’re in the Northern Hemisphere, try looking northeast this evening for two prominent constellations, Cassiopeia and Perseus. The easier to see will be Cassiopeia, which has a distinctive M or W shape. Cassiopeia represents a queen in ancient mythology, and is one of the most famous constellations in the sky. You’ll see it in the northeast this evening, and higher up in the evening sky in late fall and winter.

Milky Way’s dark matter half what we thought?

Artist's concept of the halo of dark matter surrounding our Milky Way galaxy.

Artist’s concept of the halo of dark matter surrounding our Milky Way galaxy. Image via ProfMattStrassler.com

Australian astronomers have now chimed in on the subject of why our Milky Way galaxy has fewer orbiting satellites than a prevailing theory of the universe – cold dark matter theory – says it should. They say the reason is that, according to their measurements, there’s only half the amount of dark matter in the Milky Way as previously thought, only 800 billion times the mass of our sun. Their ideas are the latest in a series of widely varying researches, all attempting to explain the “missing” Milky Way satellites.

Lifeform of the week: Owls

Snowy Owl on a snowy day. Image Credit: David Hemmings.

Snowy Owl on a snowy day. Image Credit: David Hemmings.

In fact and in fiction, owls have always turned heads.

MESSENGER spacecraft sees lunar eclipse from Mercury

Earth and Moon from Mercury orbit, with Moon entering eclipse.  Imaged on Wednesday, October 8, 2014 by MESSENGER, a spacecraft in orbit around Mercury.

Earth and Moon from Mercury’s orbit, with moon entering eclipse. Imaged on Wednesday, October 8, 2014 by MESSENGER, a spacecraft in orbit around Mercury. Image via NASA / JHU / APL. MESSENGER

The MESSENGER spacecraft – which has been orbiting the sun’s innermost planet Mercury since 2011 – made this movie of the the Hunter’s Moon passing into the Earth’s shadow on October 8, 2014. The movie consists of 31 MDIS NAC (Mercury Dual Imaging System Narrow Angle Camera) frames taken two minutes apart from 09:18 UTC to 10:18 UTC on October 8. MESSENGER made the movie from a distance of 107 million kilometers / 66 million miles.

Typhoon Vongfong approaching Okinawa

Reid Wiseman took this picture on top of the ISS showing the true power of Super Typhoon Vongfong. Image Credit: Reid Wiseman/Twitter

Reid Wiseman took this picture from top of the International Space Station, showing the true power of Super Typhoon Vongfong. Image via Reid Wiseman (@astro_reid) on Twitter

Earlier this week, Typhoon Vongfong became the strongest storm to form across the globe for 2014. The typhoon became a super typhoon with sustained winds of 180 miles per hour (mph) or 290 kilometers per hour (kph). Vongfong will gradually weaken over the next several days. Unfortunately, it will travel near Okinawa and push over mainland Japan this weekend (October 10-13, 2014) as it pushes off to the northeast. Vongfong will bring with it strong winds, heavy rain and storm surge across the area.