The nine astronauts and cosmonauts also will conduct a press briefing from the U.S. Laboratory Destiny at 1:30 p.m. Sunday. The news conference will air live on NASA Television.
Later today, one of the radiators on the newly installed S1 Truss will be remotely deployed to verify the connections established on the first spacewalk last Thursday. Its extended length will be 75 feet with each of the eight panels being 11 feet wide. The cooling system will not formally be activated until next year.
One major task inside the station today is the replacement of the exercise treadmill's vibration dampening system. The treadmill is located in the Russian Zvezda module – the station's living quarters – and is designed to significantly reduce or eliminate vibration during workouts that otherwise could negatively affect sensitive experiments being conducted on board. The unit is one of the major exercise devices aboard the station, and important in maintaining fitness during long-duration spaceflight.
Transfer work continues through much of the day while oxygen is transferred from Atlantis to high-pressure storage tanks on the outside of the Quest Airlock.
In preparation for Monday's spacewalk, the suits will be recharged with water, and tools will be configured. Prior to going to bed, all nine crewmembers will review spacewalk and airlock procedures.
The day began with a wakeup call at 4:07 a.m. for Mission Specialist Fyodor Yurchikhin. The "Aviation March," composed by Isaac Dunaevsky, is the hymn of the Moscow Aviation Institute, Yurchikhin's alma mater.