Climate modelers go back in time to simulate past Snowball Earth conditions and find that complete freeze-over is hard to achieve.
Seven thousand year-old rock paintings in the Sahara desert have, somewhat serendipitously, helped uncover evidence of ancient lake beds.
The environment can produce sudden shocks to the life of our planet through impacting space rocks, erupting volcanoes and other events.
The claim of a microbe that swaps arsenic for phosphorus may be questionable, but its implications are far-reaching.
Snowball Earths, eras in which our planet was locked in a global winter, have perplexed researchers studying how our planet unfroze itself.
The search for life on other planets focuses on water, but researchers argue that judging from our own planet a large fraction of water conditions may be inhospitable to life.
The film "Avatar" takes viewers to a fictional moon, where the alien plants glow, shoot poison leaf tips and communicate.
The possibility that life was shared between Earth and Mars could be tested with a DNA analyzer. One research team has built a prototype and plans field tests on a South American volcano.
Scientists are cooking up a replica of the surface of Saturn's moon Titan to learn more about the lakes recently discovered there.
Water vapor in planet-forming disks may block ultraviolet radiation from destroying water and other important molecules for life, according to new calculations.
Sinuous channels on the Martian surface may be evidence of more recent rainfall than expected. Researchers plan to test this hypothesis by studying sinuous streams on Earth.
A proposed space mission that aims to measure dark energy could also detect planets that current surveys are unable to find.