Not many people can say they have a doctorate in interplanetary navigation, but Tim Crain can.
While working on his PhD in Austin, Texas, in the 1990s he hoped one day to work on missions to Mars and in 2000 he landed his dream job with Nasa, at the Johnson Space Center in Houston.
“In 2000, the idea was, we would finish the space station in just a matter of years, and then the next big human spaceflight project would be to move on to Mars,” he says.
But things didn’t quite work out that way and shortly after he joined Nasa the agency’s priorities changed.
“Things took a turn, we lost [the Space Shuttle] Columbia, had the global war on terrorism, so, Mars fell off the table,” he explains.
He shifted to another Nasa programme called Constellation, an ambitious plan to return to the Moon and eventually Mars, but by 2010 it too had