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New 3D map of the cosmic web

3D map of the cosmic web at a distance of 10.8 billion light years from Earth. The map was generated from imprints of hydrogen gas observed in the spectrum of 24 background galaxies, which are located behind the volume being mapped. The coloring represents the density of hydrogen gas tracing the cosmic web, with brighter colors representing higher density.  Image credit: Casey Stark (UC Berkeley) and Khee-Gan Lee (MPIA)

3D map of the cosmic web at a distance of 10.8 billion light years from Earth. The map was generated from imprints of hydrogen gas observed in the spectrum of 24 background galaxies, which are located behind the volume being mapped. The coloring represents the density of hydrogen gas tracing the cosmic web, with brighter colors representing higher density. Image credit: Casey Stark (UC Berkeley) and Khee-Gan Lee (MPIA)

A team led by astronomers has created the first three-dimensional map of a section of the universe 10.8 billion light years away, when the universe was only a quarter of its current age. This map, built from data collected from the W. M. Keck Observatory, is millions of light-years across and provides a tantalizing glimpse of large structures in the ‘cosmic web’ – the backbone of cosmic structure.

Keep watching for Orionid meteors on October 21-22

Here is a beautiful aurora, with an Orionid meteor falling above it.  Photo taken in 2013 by Tommy Eliassen Photography in Norway.

Aurora, with an Orionid meteor falling above it. Photo by Tommy Eliassen Photography in Norway.

Video: Solar eclipse on October 23

Weather permitting, almost everyone in North America will be able to see the partial solar eclipse this Thursday. Here’s more info, including when to see the eclipse where you live

Best photos: Comet Siding Spring sweeps past Mars

Comet Siding Springs sweeps past Mars on October 19, 2014, via Rolando Ligustri.

Comet Siding Springs sweeps past Mars on October 19, 2014, via Rolando Ligustri. Used with permission.

Hurtling through space at about 35 miles (56 kilometers) per second, Comet Siding Spring (C/2013 A1) swept closest to Mars on October 19, 2014. It swept extremely close to the planet, closer than any known comet in recorded history. We’re just beginning to see the photos from this event. See the best ones here …

How often might Hawaii get a monster tsunami?

Hawaii’s evacuation maps are based in part on the 1946 tsunami, the most destructive tsunami in Hawaii’s recent history. But new research shows that mammoth tsunamis, many times the size of the 1946 event, have struck the island in the past, and may again in the future.  Image via USGS

Hawaiian residents flee the waves, in what was Hawaii most destructive tsunami in recent history, in 1946. Hawaii’s evacuation maps were based in part on the 1946 tsunami, but have been revised thanks to a new study. Image via USGS

The most destructive tsunami in Hawaii’s recent history took place in 1946. Scientists now have evidence, however, suggesting that at least one colossal tsunami, some three times larger than the 1946 tsunami and larger than any in Hawaii’s known history, struck the islands in the past. These scientists say a similar mammoth tsunami could strike again …

New seafloor map reveals thousands of seamounts

Satellite model of the North Atlantic Ocean. Image Credit: David Sandwell, Scripps Institution of Oceanography, UC San Diego.

Satellite model of the North Atlantic Ocean. Image Credit: David Sandwell, Scripps Institution of Oceanography, UC San Diego.

Vast unexplored areas of the ocean have now been mapped with new satellite data and scientists have discovered thousands of previously uncharted seamounts in addition to an extinct spreading ridge in the Gulf of Mexico.

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!

Orionid meteor shower on night of October 20-21

Halley's Comet at its 1910 visit.  The famous astronomer Edward Emerson Barnard at Yerkes Observatory in Wisconsin took this photo.  Via Wikimedia Commons.

Halley’s Comet at its 1910 visit. The famous astronomer Edward Emerson Barnard at Yerkes Observatory in Wisconsin took this photo. Via Wikimedia Commons.

Tonight … October 20, 2014 … is the best time for watching the annual Orionid meteor shower. And an awesome shower it is! For one thing, it stems from debris from the most famous of all comets, Comet Halley. In fact, the object in the picture at top isn’t a meteor. It’s Comet Halley itself. Debris in the orbit of this comet – the Orionid meteor stream – is now encountering Earth’s atmosphere. The meteors will become visible in their greatest numbers tonight, and especially in the dark hours before dawn tomorrow morning (October 21). At the peak, from a dark site, you might expect to see about 25 meteors per hour.

Everything you need to know: Orionid meteor shower

The Orionids radiate from a point near the upraised Club of the constellation Orion the Hunter.  The bright star near the radiant point is Betelgeuse.

The Orionids radiate from a point near the upraised Club of the constellation Orion the Hunter. The bright star near the radiant point is Betelgeuse.

Details on 2014’s Orionid meteor shower. It’ll peak on the morning of October 21. If you’re hankering to watch some meteors, try this shower! 2014 is a good year for them.