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Image courtesy Tim Haynes
Science Wire | Oct 09, 2015

Why does the sun look red at sunset?

As the sun sets, it looks redder and redder as it gets closer to the horizon. Why does this happen?

UW astronomers Rory Barnes and Victoria Meadows of the Virtual Planetary Laboratory have created the “habitability index for transiting planets” to compare and rank exoplanets based on their likelihood of being habitable. Image credit: Rory Barnes
Science Wire | Oct 07, 2015

Where to look for ET life? Habitability index aids in the search

Powerful telescopes coming soon. Where shall we point them to find extraterrestrial life? Astronomers have created a way to help prioritize exoplanets.

Tonight | Oct 04, 2015

Find constellations of the Zodiac

Today’s sky chart shows the constellations of the Zodiac that are up after nightfall on these October evenings.

NASA's New Horizons captured this high-resolution enhanced color view of Charon just before the spacecraft's closest approach on July 14, 2015. The image combines blue, red and infrared images taken by the spacecraft’s Ralph/Multispectral Visual Imaging Camera (MVIC); the colors are processed to best highlight the variation of surface properties across Charon. Charon’s color palette is not as diverse as Pluto’s; most striking is the reddish north (top) polar region, informally named Mordor Macula. Charon is 754 miles (1,214 kilometers) across; this image resolves details as small as 1.8 miles (2.9 kilometers). Image credit: NASA/JHUAPL/SwRI
Science Wire | Oct 02, 2015

Best yet images of Pluto’s moon Charon

Beautiful and fascinating images from the New Horizons spacecraft reveal the large moon’s violent history.

Photo Credit: sandcastlematt
Science Wire | Oct 02, 2015

Why do tree leaves change color in fall?

In the fall, the leaves of some trees turn yellow, orange or red. The bright colors are wonderful to behold. But do they have some hidden purpose?

Image Credit: Aramgutang
Science Wire | Oct 01, 2015

What’s the birthstone for October?

October has two birthstones – opal and tourmaline.

This original painting by James Havens of Ugrunaaluk kuukpikensis, the new species of duck-billed dinosaur, illustrates a scene from ancient Alaska during the Cretaceous Period.
Science Wire | Sep 28, 2015

Newly discovered dinosaur roamed northern Alaska

Hadrosaur was a truly polar dinosaur that endured months of winter darkness and probably experienced snow.

Eclipses for Beginners
Science Wire | Sep 26, 2015

Why no eclipse every full and new moon?

There are typically 12 full moons and 12 new moons every year, but only four to seven eclipses.

Autumn dawn. Dave Sodano wrote, " Went to Steamboat Springs Colorado this weekend in search of fall colors. Found this instead. The 1st cold night of the season on a summer warm lake produced this lovely mist and deep morning colors."
Today's Image | Sep 25, 2015

Photos from friends: Signs of autumn

Happy autumn (or spring, if you’re in the Southern Hemisphere)! Enjoy the photos.

Photo credit: NASA Goddard
Science Wire | Sep 15, 2015

2015 Arctic sea ice minimum 4th lowest

The 2015 Arctic sea ice minimum summertime extent is the 4th lowest since observations from space began, according to a NASA analysis of satellite data.