Depending upon favourable weather conditions, Indian-American astronaut Sunita Williams will return to Earth aboard the Atlantis shuttle and join her friends and family on June 19, after her six months stay in space, the longest period spent by a woman there.

This was revealed by NASA sources following certification of Flight Readiness by its senior managers on May 30 and 31 at the Kennedy Space Centre in Florida, where Atlantis got a green signal for launch on June 8.

Everyone on Earth, especially Williams' parents, Deepak Pandya, a renowned neuro-anatomist and mother Bonnie Pandya, are eagerly awaiting her return.

"Although we have been in touch via polycom, video-conferencing device, and have seen her during this period, but it will be a joy to see her after so many months," Deepak Pandya told PTI.

Williams will be in rehab for at least 45 days, depending on her overall health condition, after which both her parents will join her in Houston, where she has been living since 1998 after being selected as astronaut by NASA.

Meanwhile, the countdown for the space shuttle Atlantis' STS-117 mission will start at 9 pm EDT on June 5, at the T-43 hour point. The countdown includes 27 hours, 32 minutes of built-in hold time leading to a preferred launch time at approximately 7:38 pm EDT on June 8. The launch window extends an additional five minutes.

During the 11-day mission, Atlantis' crew will resume construction of the International Space Station, working with the station crew to install the girder-like S3/S4 truss segment, unfold a new set of solar arrays and retract one array on the starboard side of the station.

This mission is the 118th space shuttle flight -- the 28^th flight for Atlantis and the 21st US flight to the International Space Station. STS-117 is scheduled to land at NASA's Kennedy Space Centre, Fla., on June 19. Atlantis' last mission was STS-115 in September 2006.

For the upcoming STS-117 mission, Atlantis rolled out to Launch Pad 39-A from Kennedy's Vehicle Assembly Building on May 15.

Atlantis originally was targeted for launch in March, but a hailstorm damaged foam insulation on the shuttle's external fuel tank and forced managers to roll the spacecraft back into the Vehicle Assembly Building to make repairs.

With the refurbishment of Pad 39-A, this launch will be the first from the pad in four years.

STS-117 Commander Rick Sturckow, Pilot Lee Archambault, and mission specialists Jim Reilly, Patrick Forrester, Steven Swanson, John 'Danny' Olivas and Clayton Anderson are scheduled to arrive at the Kennedy Space Centre on June 4.

Anderson will replace Williams, the Expedition 15 Flight Engineer, on the International Space Station.