741–760 of 804 results

Solar System

Getting To Know Mercury

Planetary scientists have gathered in Houston, Texas, to get the latest news on what NASA's Messenger spacecraft learned when it zipped past the innermost planet two months ago.

Space Missions

Ring Around a Saturn Moon?

During a close flyby of Saturn's largest icy moon in late 2005, several instruments aboard Cassini sensed (but didn't actually "see") what appears to be a trio of thin rings and a dust disk surrounding Rhea.

Space Missions

Four Martian Landslides Caught in the Act

A scarp along the edge of the Martian north polar cap is more active than anyone expected.

Space Missions

Ulysses Says Goodbye

After spending more than 17 years in space, a durable solar sentinel has lost its radio voice and its fuel lines will soon freeze solid.

Space Missions

See the Doomed Spy Satellite!

Until it reenters the atmosphere — whole or in pieces — in the days ahead, you can see the decaying satellite USA 193 with your own eyes. Here's how to find it.

Space Missions

Space-Station Astronomy

Solar telescopes are set to be installed on the International Space Station today. A trio of instruments will be added to the new Columbus module.

Space Missions

NASA Wants You!

The US space agency wants to give its soon-to-be-launched gamma-ray observatory a new name, and it has opened the floor for nominations. Do you have the perfect moniker for the next Great Observatory?

Space Missions

Mercury's "Better Half"

When it swept by the innermost planet on January 14th, NASA's Messenger spacecraft showed us a side of Mercury never before seen. After two weeks of intensive study, mission scientists have shared some of the flyby's intriguing results — including views of a "spidery" crater that has them stumped.

Stardust encounters Comet Wild 2

Solar System

A Stardust-Free Comet

When NASA sent a spacecraft to grab samples of a comet and return them to Earth, scientists had high hopes that they'd finally be able to decipher how the solar system formed. Boy, were they wrong!

Space Missions

A Bird's-Eye View of the Sun

What's it like to coast high over our star? The European-built spacecraft Ulysses is doing that right now — for its third and likely final time.

Messenger's Mercury

Space Missions

Reunion with Mercury

For the first time in nearly 33 years, mission controllers have guided a spacecraft past Mercury, a fire-and-ice world that may hold many keys to the solar system's formation.

Hubble Servicing

Science and Space Policy

High Hopes for Hubble

Preparations are well under way for the August 2008 servicing mission to the Hubble Space Telescope.

Space Missions

Cassini's Popularity Contest

After a month-long contest, the Cassini Imaging Central Laboratory for Operations (CICLOPS) has announced which images of Saturn are fan favorites.

Space Missions

You Can't Go Home (or Work) Again

Visiting where I worked 20 years ago reveals a changed place.

Space Missions

Deep Impact's New Assignments

Put to sleep after its smash success in 2005, one of NASA's interplanetary craft is getting a chance to search for extrasolar Earths and to visit a second comet.

Space Missions

Lightning on Venus

The world next door seemed hellish enough with an atmosphere 90 times the sea-level pressure on Earth and surface temperature of 900°. Now, scientists say, there's lots of lightning — and what little water it has seems to be escaping to space.

Astronomy and Society

Earth at Night: Not a Pretty Sight

Rosetta's nighttime snapshots of the Eastern Hemisphere show that the fight against light pollution has a long way to go.

Space Missions

Call for Images of Venus

Venus Express project scientists are inviting amateur and professional astronomers to contribute Earth-based images of the planet made at infrared, visible, and ultraviolet wavelengths.

Space Missions

Good Morning Earth

The Kaguya spacecraft provides a nice way to start the day with a look back home.

Space Missions

Rosetta Attacks!

Briefly mistaken for an asteroid headed toward Earth, a European-built comet chaser zips by en route to its deep-space rendezvous.