A Scottish science student who hopes to be the first human on Mars has been selected from hundreds of candidates across the world to start training for a mission to the Red Planet. Emily MacDonald, 24, will join a team of six researchers living in a replica space probe placed in the Canadian Arctic to simulate the extreme Martian weather conditions. She will spend three weeks conducting tests in the cramped 27ft diameter pod, known as a human habitation module, with outside temperatures reaching -30C. Miss MacDonald, from Troon, Ayrshire, who is studying for a PhD in astrophysics at Exeter College, Oxford, was selected from more than 400 applicants to take part in the experiment. After completing her spell at the Mars Arctic Research Station on Devon Island, in July, she plans to spend time in a second replica Mars station in the Utah desert.