A discarded chunk of a Russian rocket is forcing six International Space Station astronauts to seek shelter in escape capsules.
NASA says the space junk will barely be close enough to be a threat, but if it hits the station it could be dangerous, so the astronauts - two Americans, three Russians and a Dutchman - are waking early to climb into two Soyuz vehicles, ready to rocket back to earth just in case.
The debris is supposed to come closest at 2.38am EDT (5.38pm AEDT today).
The space junk wasn't noticed until yesterday, too late to move the International Space Station out of the way.