Overview
- Deinococcus radiodurans endured simulated impact shocks of 1–3 gigapascals, with near-total survival at about 1.4 GPa and roughly 60% at 2.4 GPa in PNAS Nexus experiments.
- Researchers used a gas gun to fire a projectile at microbes sandwiched between metal plates at up to 300 miles per hour, and the steel setup failed before the bacteria were eliminated.
- Gene expression analyses indicated stress responses and prioritized cellular repair in survivors, even as higher pressures produced some membrane ruptures and internal damage.
- The results strengthen the plausibility of lithopanspermia but do not prove interplanetary transfer of life, and the authors stress the limits of a single-species, lab-based test.
- Space policy experts and the team note the need to reassess contamination controls, particularly for Mars’s moon Phobos where ejecta may arrive after experiencing lower peak pressures, and follow-up tests will probe other organisms and repeated-impact effects.