Sunita and six other astronauts, who came on June 10 to fetch her bid farewell to her replacement Clayton Anderson and two Russian cosmonauts on the International Space Station (ISS) before the hatches between their spaceship and the station closed at 6.51 pm on Monday (4.21 am IST on Tuesday).
"I'm sad to say goodbye, but that means progress is being made and it's time for the International Space Station to grow a little more," Williams told ground control before the astronauts floated into space shuttle Atlantis that would take them home.
Undocking at 10.42 am (8.12 pm IST) on Tuesday, Atlantis is scheduled to touchdown at Kennedy Space Centre, Florida at 1.54 pm (11.24 pm IST) on Thursday, US space agency Nasa said. Sunita had set off from here on December 9 on space shuttle Discovery on what was to become the longest space journey by a woman.
Sunita, who with four excursions also holds the record for most space walks by a woman, crossed the new milestone on Saturday surpassing the 188-day, 4hour mark set by US astronaut Shannon Lucid in 1996 on a mission to the Russian Mir space station.