The Murchison meteorite has been sitting in collections since 1969, when it broke apart over the Australian state of Victoria and scattered in pieces across paddocks and roadsides. Researchers have picked at it for decades. It is one of the most studied rocks not from this planet, stuffed with organic molecules, and a standing puzzle: which of those molecules came from space, and which it picked up here. A team preparing an instrument bound for Mars went looking for an New! Sign up for our...