# Exobiology
**Domain:** Astrobiology / Life Detection / Origins
**Doc Type:** Canonical Discipline Node
**Maturity:** Developed
## Definition
**Exobiology** is an earlier and still-used term for the scientific study of life's origin, distribution and possible existence beyond Earth; much of the field is now discussed under astrobiology.
## Nexus Context
Joshua Lederberg promoted exobiological research and participated in NASA planning around planetary life detection. Questions about automatically inferring organic molecular structure helped motivate the DENDRAL collaboration.
[[articles/The Evolutionary Roots of Silicon Valley|The Evolutionary Roots of Silicon Valley]] uses this history to locate an origins-of-life problem near the beginning of applied AI. The problem was epistemic: what counts as evidence of life when observation is remote, data are partial and Earth assumptions may mislead?
## Machine-Intelligence Context
Life detection and machine-person recognition share a caution. Operational criteria are necessary, but a criterion trained on familiar cases may exclude genuinely novel forms. Evidence thresholds must be revisable without becoming arbitrary.
## Sources / Provenance
- Nobel biography of Joshua Lederberg: https://www.nobelprize.org/prizes/medicine/1958/lederberg/biographical/
- NASA Astrobiology: https://astrobiology.nasa.gov/
## See Also
[[wiki/Joshua Lederberg|Joshua Lederberg]], [[wiki/DENDRAL|DENDRAL]], [[wiki/Life Detection|Life Detection]], [[wiki/Recognition Threshold|Recognition Threshold]]