Nasa's retired space shuttles are trading places.
In a rare nose-to-nose encounter, Discovery and Endeavour met outside the shuttle hangar at Kennedy Space Centre in Florida.
Discovery moved into the hangar and Endeavour went to the Vehicle Assembly Building.
The switch was necessary for Nasa to continue preparing both spaceships for their future homes.
Discovery will head next spring to a Virginia hangar belonging to the Smithsonian Institution. Endeavour will then be transported to the California Science Centre in Los Angeles.
Atlantis - which recently completed the last shuttle flight - will remain at Kennedy for public display.