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Posts by EarthSky

cropped-universe-map
Science Wire | Oct 21, 2014

New 3D map of the cosmic web

A team of astronomers has created the first three-dimensional map of the adolescent universe, just 3 billion years after the Big Bang.

Artist's impression of the Milky Way. Its hot halo appears to be stripping away the star-forming atomic hydrogen from its companion dwarf spheroidal galaxies.  Image credit: NRAO/AUI/NSF
Science Wire | Oct 16, 2014

Milky Way strips nearby galaxies of star-forming hydrogen

Astronomers have discovered that our nearest galactic neighbors are devoid of star-forming gas, and that our Milky Way is to blame.

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Science Wire | Oct 16, 2014

What are super-Earths made of?

Astronomers struggle to learn about super-Earths – bigger than our Earth, smaller than Neptune – the most common type of planet found by the Kepler spacecraft.

The 'north pole' -- that is, the direction of magnetic north -- was reversed a million years ago. This map shows how, starting about 789,000 years ago, the north pole wandered around Antarctica for several thousand years before flipping 786,000 years ago to the orientation we know today, with the pole somewhere in the Arctic. Image courtesy of University of California - Berkeley
Science Wire | Oct 16, 2014

Earth’s last magnetic reversal took less than 100 years

A study demonstrates that Earth’s last magnetic reversal – 786,000 years ago – happened in roughly the span of a human lifetime.

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Science Wire | Oct 15, 2014

Spacecraft catches Mars atmosphere in act of escaping

Earth’s atmosphere is leaking into space, too, but only very, very slowly. Meanwhile, Mars is thought to have lost much of its atmosphere already.

auriga-chart-cp
Tonight | Oct 15, 2014

Close-up of constellation Auriga the Charioteer

Auriga the Charioteer is easy to spot on these October nights. Come to know its bright star Capella and the little asterism called The Kids.

Photo credit: Martin Heigan
Science Wire | Oct 14, 2014

Crocodiles work as a team to hunt their prey

Crocs are able to conduct highly organized game drives. They might be second only to humans in their hunting prowess, says a researcher.

Upside-down Cassiopeia on Mercator globe.
Tonight | Oct 14, 2014

Star of the week: Schedar lies at the Queen’s heart

For much of the Northern Hemisphere, on clear nights you can always see the brightest star in the constellation Cassiopeia.

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Tonight | Oct 11, 2014

Find constellations of the Zodiac in October night sky

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

Image courtesy Tim Haynes
Science Wire | Oct 10, 2014

Why does the sun look red at sunset?

As the sun sets, it looks redder and redder as it gets closer to the horizon. Sometimes you can see a gradation of color a across the sun’s surface. Why does this happen?