Odds are 50/50 that the dinosaur that left this mark was a Tyrannosaurus rex, says the scientist who announced the find. Whatever it was, it was big.

The first set of highly detailed color images from a Mars Reconnaissance Orbiter camera will help scientists chose a landing site for a new rover due to be launched in 2009.

The first ever high-resolution images of Iapetus have helped crack the mystery of its rare color scheme.

Moon shuttles, rocket racers, and Mars bases are just some of the space highlights historians will commemorate 50 years from now, experts say.

Typhoon lashes Vietnam, Russia remembers Sputnik, volcano blows in Yemen, and more.

In a dramatic impact never before seen by scientists, a solar hurricane detached the Encke comet's plasma tail.

Thousands of sparkling young stars are enveloped by the giant nebula NGC 3603, located in the Milky Way about 20,000 light-years away from our solar system.

See the tragic results of a freak accident on an Kenyan river, and learn more about the animals' epic annual migration.

Oktoberfest starts flowing, protesters march in Myanmar, Mars rover reaches a crater landmark, and more.

Put down those knives—this transparent amphibian allows for observation of its innards without the need for dissection.

Video: Transparent Frog

Early Polynesians traveled thousands of miles - from Hawaii to Tahiti - for trade and exploration, suggests a new study of woodworking tools.

A striking seaweed, ribbon-like metal, and twisted geometry are just some of the winners of the 2007 International Science and Engineering Visualization Challenge.

A white-lipped snake and a fungus-like orchid are among the 11 new species found by WWF surveys in a remote tropical forest in central Vietnam.

A new rush to harvest iron, coal, and other minerals in Australia's Pilbara region is creating fortunes. But the unprecedented boom is also making life difficult for tourists, locals, and native groups.

Astronomers working with the SOHO probe have found their first regularly returning comet, a small tail-less body that flies by the sun every four years.