In 2007, samples of bacteria and a rock-dwelling lichen were attached to the heat shield of a re-entry capsule. As the capsule scorched through the Earth’s atmosphere, the samples were exposed to temperatures of over 2,000 degrees Centigrade for thirty seconds. In the process, the rocks partially melted and crystallised into new forms. When the remains were examined, there was no sign of any living cell whatsoever.36
