Ocean world near Saturn top contender for life beyond Earth

A tiny, ice-encrusted ocean world orbiting Saturn is now a hotter-than-ever candidate for potential life.

NASA's Cassini spacecraft has detected hydrogen molecules in the geysers shooting off the moon Enceladus, possibly the result of deep-sea chemical reactions between water and rock that could spark microbial life, scientists announced Thursday.

NASA and others are quick to point out this latest discovery does not mean there's life on Enceladus (ehn-SEHL'-uh-duhs), but that there may be conditions favorable for life.

Tiny tubes in Canadian rock may be oldest known fossils

Tiny tubes and filaments in some Canadian rock appear to be the oldest known fossils, giving new support to some ideas about how life began, a new study says.

The features are mineralized remains of what appear to be bacteria that lived some 3.77 billion to 4.28 billion years ago, the scientists said. That would surpass the 3.7 billion years assigned to some other rock features found in Greenland, which were proposed to be fossils last August.

7 Earth-size worlds found orbiting star; could hold life

For the first time, astronomers have discovered seven Earth-size planets orbiting a single nearby star — and these new worlds could hold life.

This cluster of planets is less than 40 light-years away in the constellation Aquarius, according to NASA and the Belgian-led research team who announced the discovery Wednesday.

Life on Mars? NASA says planet appears to have flowing water

Mars appears to have flowing rivulets of water, at least in the summer, scientists reported Monday in a finding that boosts the odds of life on the red planet.

"Mars is not the dry, arid planet that we thought of in the past," said Jim Green, director of planetary science for NASA.