It sounds like a sci-fi movie, or the weirdest series of Big Brother ever. Eight volunteers wearing snazzy red jumpsuits seal themselves into a hi-tech glasshouse that’s meant to perfectly replicate Earth’s ecosystems. They end up starving, gasping for air and at each other’s throats – while the world’s media looks on.
But the Biosphere 2 experiment really did happen. Running from 1991 to 1993, it is remembered as a failure, if it is remembered at all – a hubristic, pseudo-scientific experiment that was never going to accomplish its mission. However, as the new documentary Spaceship Earth shows, the escapade is a cautionary tale, now that the outside world – Biosphere 1, if you prefer – is