Microbes collected from the edge of space have been brought back to life in the lab. This enabled the high-flying organisms to be identified, almost two years after they were found in air samples collected by a weather balloon cruising at 41,000 metres (135,000 feet) over southern India. How the bugs got there is not known, but there are three possibilities: they were carried up on winds, they sneaked into the samples on Earth or they have flown through space and are aliens making their way down to our planet.