Indian American astronaut Sunita Williams is preparing to return home on Thursday, a bit nervous about mother Earth's pull after a 194-day record space odyssey without a tug of gravity.
Weather permitting, US space shuttle Atlantis with Williams and six fellow astronauts on board is scheduled to touchdown at the Kennedy Space Centre, Florida at 1.55 pm (11.25 pm IST) on Thursday, US space agency NASA said.
But cloudy skies and thunderstorms could keep Atlantis in orbit for a 14th day. Low-lying clouds and possible thunderstorms could delay the shuttle's landing until Friday or later.
The shuttle has enough fuel and supplies to stay in space through Sunday, NASA said.
The shuttle blasted off on June 8 to fetch Williams and install new solar power panels aboard the International Space Station.
Atlantis crew have set up a reclined chair for Williams, who has not felt the tug of gravity for more than six months. She is reported to have admitted that despite her disciplined and rigorous exercise routine, she was a little nervous about re-adapting to Earth's gravity.
"I've never done this before," said Williams who not only set an endurance record for the longest space flight by a woman during her very first space journey, but with four excursions spread over 29 hours and 17 minutes set a new record for most space walks by a woman.
As the flight crew worked on preparing Atlantis for landing, Sunita Williams and three other astronauts stowed equipment and packed loose items in the shuttle's mid-deck.
Shuttle commander Frederick Sturckow, pilot Lee Archambault and flight engineer Steven Swanson test-fired Atlantis' steering jets and checked landing systems in preparation for touchdown.
Williams has been replaced at the station by American astronaut Clayton Anderson, who is scheduled to stay aboard the outpost until October.