Sunita Williams and the two co-astronauts on her expedition are winding down their last week aboard the International Space Station, beginning a countdown for the return to Earth of the record-setting Indian-American cosmonaut after four months in orbit.

The home-bound trio of Williams, flight engineers Aki Hoshide and Yuri Malenchenko, will undock at 2226 GMT Sunday (0356 IST Monday) and land in Kazakhstan at 0153 GMT Monday (0723 IST).

Mission managers have completed their Soyuz TMA-05M landing readiness review and there will be a ceremonial change of command from Williams to flight engineer Kevin Ford on Saturday, reports said.

After Expedition 33 undocks, Ford will become Expedition 34 commander staying behind with Flight Engineers Oleg Novitskiy and Evgeny Tarelkin.

They will be waiting for a new trio of flight engineers — Chris Hadfield, Tom Marshburn and Roman Romanenko — who are conducting Soyuz simulations in Star City, Russia and preparing for their December 19 launch to the orbital laboratory.

Williams, who set a record for the longest stay for a woman astronaut, spent most of her afternoon preparing hardware to upgrade the wireless access points for the station’s local area network. While preparing for her departure earlier in the day, she also had a radio talk with science students from Gujarat.

Hoshide spent most of the day yesterday prepacking gear and preparing for his Sunday departure. He also spent some time talking with university students who visited Tsukuba Space Center in Japan.

Tarelkin and Novitskiy worked on cargo stowage and transfers from the two docked Progress resupply ships. The duo also worked throughout the Russian segment conducting ongoing science and routine maintenance.

Malenchenko worked on stowing gear inside the Soyuz TMA-05M spacecraft he will ride home on Sunday. He also joined his fellow cosmonauts for an interview on a popular Russian television show.

Ford, while in the midst of crew handover activities, spent some time on Crew Medical Officer computer-based training. He also spent a few hours on Wednesday working on ultrasound background noise equipment.

The equipment may help differentiate pressure leak sounds from the background noise of the station’s environment.

Meanwhile, a communications outage at the Russian Mission Control Center in Moscow temporarily interrupted telemetry between Russian flight controllers and Russian segment systems on the International Space Station yesterday.

The outage is not expected to have any impact on the scheduled landing of the Soyuz TMA-05M spacecraft bringing home the three cosmonauts after four months in orbit.

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