Professor Davies, an astrobiologist and professor of natural philosophy at Macquarie University in Sydney, expects that earth’s first Martian explorers may be similar to Australia’s first colonists. “I see no particular reason that the astronauts who go to Mars should come back again,” Professor Davies said. “I’m in favour of a one-way mission to Mars – it would dramatically cut the costs. “You might think that’s terrible – you’re sending them to their deaths, but that’s not what I had in mind. “I have in mind resupplying them every two years as a sort of cycle of the Martian orbit. “We could send on the food parcels from home and other things that are required to keep a tiny colony, maybe four or six people, going perhaps for many years.”