OPPONENTS of the idea that life originated on Mars, and came to Earth on meteorites, have always been able to point to the huge impacts needed to eject rocks from the Martian surface. Surely, they argue, this would have killed any life they carried. Not so, says a study of the forces involved.
Rocks can be ejected when a giant meteorite impact sends an intense pressure wave across the surface of a planet. To see if microbes could withstand these pressures, Dieter Stoffler at the Fraunhofer Institute for High-Speed Dynamics in Freiburg, Germany, and his team put thin layers of…
