It's one small sleep for mankind, at least for astronauts on the International Space Station, with the sun rising and setting every 90 minutes.
But while the view maybe spectacular many suffer from sleep deprivation, averaging just six hours at a time.
ITV News' Sejal Karia reports:
Dr. Charles Czeisler of the Harvard Medical School said: "Where people are burning the candle at both ends and not getting enough sleep, after about a week or two it can build up the same adverse effects as staying up all night for one or two consecutive nights."
Sleeping in chambers to stop themselves floating away, the astronauts currently zip themselves up in bags strapped to the wall.
Nasa says its committed to helping astronauts sleep, but if space exploration is going to continue Dr Charles Czeisler said it is something that is going to have to be worked on.
With missions extending to over a year he said: "A mission to mars would be about 18 months, so it's really important to address these issues."