A spacecraft made of folded paper may sound far-fetched, but Japanese scientists believe it could be possible for a paper plane launched from space to reach Earth intact.
Researchers at the University of Tokyo have tested small, origami planes made of special paper for 30 seconds in 250-degree Celsius heat and wind at seven times the speed of sound.
The planes survived the wind tunnel test intact.
The theory is that paper craft, being much lighter than space shuttles, may escape the worst of the friction and heat that much heavier space shuttles face on re-entry to the atmosphere.
'Paper planes are extremely light so they slow down when the air is thin and can gradually descend,' said Shinji Suzuki, a professor of aerospace engineering.
Mr Shinji said the technology might one day be used for unmanned spacecraft.
The team has asked a Japanese astronaut to release the 20cm long planes, made from paper chemically treated to resist heat and water, from the International Space Station to see if they make it back to Earth.
It will take several months for the craft to reach Earth and there is no way to predict their landing spot if they make it.
'It's going to be the space version of a message in a bottle. It will be great if someone picks one up,' he said.
'We are thinking of writing messages on the planes saying 'if found, please contact us' in a couple of languages.'
