The European Space Agency (ESA) is planning research into the possibility of inducing a hibernation-like state in humans.

It would help astronauts cope with the psychological demands of decades-long journeys and less space and food would be needed on such missions, so spacecraft would be lighter and easier to launch.

One route of inquiry centers on DADLE, a substance with opium-like properties. An injection of DADLE is known to trigger hibernation in ground squirrels during the summer season. It also seems to send cultures of human cells to sleep.

ESA wants to send a human mission to Mars in 2030.