Approximately 2.8 Myr before the present our planet was subjected to the debris of a
supernova explosion. The terrestrial proxy for this event was the discovery of live atoms of^
60Fe in a deep-sea ferromanganese crust. The signature for this supernova event should
also reside in magnetite (Fe 3 O 4) magnetofossils produced by magnetotactic bacteria
extant at the time of the Earth-supernova interaction, provided the bacteria preferentially
uptake iron from fine-grained iron oxides and ferric hydroxides. Using empirically derived�…