If life as we know it exists on the red planet, it would have to be deeper under the surface than current probes are able to detect, a European team concludes.

A resurgence of bugs in streams contaminated by a sulfur mine shows that cleanup efforts are restoring water quality and creating a healthy ecosystem.

Mars may still house large reservoirs of the water and carbon dioxide that once formed the planets ancient atmosphere, new research suggests.

An unusual chromosome previously known only in West Africans has been discovered in white people from northern England, researchers report.

Rain forest groups trained to use GPS devices are creating maps to help win territorial disputes and protect their forests from mining and logging.

Egg-producing male fish are unusual but no longer uncommon in parts of the Washington, D.C.-area river. A new government report may help answer why.

Scientists in Brazil may have finally solved the centuries-old mystery of what causes the phenomenon known as ball lightning.

An exotic form of diamond found only in Brazil and the Central African Republic may have brought to Earth by an asteroid, new research suggests.

Jittery fliers can take heart. NASA is developing two new technologies to help pilots steer clear of erratic, gusty winds.

This week: skiers gear up for championship, holy men gather in India, citrus freezes in California, a leopard attacks city dwellers, and more.

This week: "weirdest" species get conservation attention, humans and Neandertals may have interbred, manatees "super" senses, new Jamestown findings, more.

Comet McNaught—the brightest comet in 40 years—could be the last thing sky-watchers see if they aren't careful, astronomers warn.

The agony of a ghost limb can be all too real for amputees. But recent experiments suggest that an unreal treatment may hold the key to a cure.

A quintet of NASA probes will study what triggers the strong magnetic storms that make the northern lights dance and will help improve space weather predictions.

This week: new stem cell source found, 2007 may be hottest year on record, Louisiana slipping into Gulf, fish smell their way home, new bat discovered, and more.