Magnetotactic Bacteria
Bacteria that biomineralize intracellular magnetite (Fe₃O₄) or greigite crystals (magnetosomes) and align passively with geomagnetic field lines. The crystals’ size, shape, and crystallographic purity are tightly biologically controlled, making them candidate biosignatures preservable in sediments long after the cells themselves are gone.
Vault appearances
- abscicon26 (May 2026): Felisa Wolfe-Simon poster proposing magnetotactic-bacteria magnets as life signs on energy-poor exoplanets — where slow biology might still produce durable mineral signatures even when atmospheric biosignatures are too faint (src-abscicon26-media-tips-1-2026-05).