Milky Way’s dark matter half what we thought?

Australian astronomers say our Milky Way galaxy has only half the dark matter we thought it did. If so, it explains the shortage of Milky Way satellites.

Active moon volcanos in geologically recent times

Last volcanic activity on moon thought to be a billion years ago. Now small lava flows on moon’s dark plains suggest activity as recently as 50 million years ago.

MESSENGER spacecraft sees lunar eclipse from Mercury

The MESSENGER spacecraft, now orbiting Mercury, caught the images to make this movie of last Wednesday's lunar eclipse. See Earth and moon from Mercury!

Mapping the weather on an extreme exoplanet

Scientists using the Hubble Space Telescope have completed the first map of temperature and water vapor on a "hot Jupiter," an exoplanet called WASP 43b.

First named feature on a comet!

Scientists have named one of the largest boulders on Rosetta’s comet after an Egyptian pyramid.

Join EarthSky’s Deborah Byrd at online viewing of total lunar eclipse

Slooh.com invites stargazers worldwide for an online viewing of the total eclipse of the moon on October 8. Deborah Byrd will be on hand as a special guest.

Is the October 8, 2014 full moon a supermoon?

There's disagreement on whether the October 8, 2014 full moon should be called a supermoon. If it is one, it's a super Hunter's Blood Moon ... in eclipse.

Mega flares from a mini star

You've heard of X flares from our sun? This mini star's biggest flare - seen in April, 2014 - was 10,000 times bigger than the biggest known solar X flare.

What is the moon’s Ocean of Storms?

Oceanus Procellarum - the lunar Ocean of Storms - is a vast volcanic plain, thought to have been created in an ancient asteroid impact. More recently, scientists came to believe it formed via processes within the moon itself.

U.S. and India to collaborate on Earth and Mars missions

Both NASA and the Indian Space Research Organization placed spacecraft in orbit around Mars last month. They'll join forces on an Earth-orbiting mission set for 2020.

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