Life beyond Earth
Explore ocean worlds, planetary habitability and the scientific search for life. Conditions that might support life and evidence of life are separate questions.
Explore the records
7 entriesBiosignatures
Potential indicators of biological processes require environmental context and careful testing of nonbiological explanations.
Cassini mission
The spacecraft investigation of Saturn that transformed research on Enceladus and other icy worlds.
Enceladus
An ocean beneath the ice. Cassini revealed a world with liquid water, organic chemistry and energy sources — compelling conditions for research into habitability.
Europa
Jupiter’s icy moon is a major target in the search for environments that could support life. Evidence for an ocean does not establish that it is inhabited.
The habitable zone
A useful astronomical starting point: orbital distances at which surface liquid water might be possible under suitable conditions.
Mars
Mars is a target of planetary exploration and research into past environments; claims about life require their own evidence and source attribution. The retained NASA overview covers possible water-related settings, biosignature searches, climate, geology, and human-exploration conditions, but it does not document confirmed Martian life, a confirmed biosignature, a completed sample return, or human-mission capability.
TRAPPIST-1
The supplied 2017 record describes TRAPPIST-1 as a transiting planetary system around an ultracool dwarf. It reports at least seven planets similar to Earth in radius and mass transiting the host, an 18.77 d period for the outermost planet TRAPPIST-1h, and a linked three-body resonant chain. The supplied material does not establish life or habitability.