01
Origin of Life
Abiogenesis concerns the transition from nonliving chemistry to systems possessing characteristics associated with life. The complete historical pathway remains unresolved.
02
Habitability
Habitability depends on physical and chemical conditions capable of supporting sustained biological processes. The relevant conditions can differ substantially across environments and possible forms of life.
03
Biosignatures
A biosignature is an observation that could provide evidence for biological activity. Robust interpretation requires distinguishing biological explanations from abiotic processes that can produce similar signals.
04
Search for Extraterrestrial Intelligence
SETI searches for technological or otherwise artificial signatures that could indicate extraterrestrial intelligence. A convincing detection would require strong evidence that the signal cannot be explained naturally or by human technology.