Disciplines

The study of how life began — the chemistry that turned simple molecules into self-replicating systems on the early Earth, and whether the same steps could happen elsewhere. A question that frames the entire search for life beyond Earth.

What makes a world able to host life — liquid water, an energy source, the chemical building blocks, and a stable enough environment for long enough. Habitability is judged by these factors, not by any detection of life.

The search for signs of life — atmospheric gases, surface features, and chemical patterns that life could produce — and the rigorous work of telling a true biosignature from a false positive made by non-living processes.

The search for signs of technology — radio and optical signals, and other technosignatures — carried out by the SETI Institute and programs like Breakthrough Listen. A search for intelligence, distinct from the search for microbial life.

The icy moons with liquid-water oceans beneath their shells — Europa, Enceladus, and Titan — now the most promising places to search for life in the Solar System, targets of the Europa Clipper and Dragonfly missions.

The discipline of preventing contamination — protecting other worlds from Earth microbes carried by spacecraft (forward contamination), and protecting Earth from any material returned from them (backward contamination), so the search for life is not fooled and no harm is done.