For the first time since early 2003, the International Space Station is home to three crew members. European Space Agency astronaut Thomas Reiter joined Expedition 13 following Space Shuttle Discovery's mission earlier this month.

Reiter, who serves as the expedition flight engineer, Commander Pavel Vinogradov and Flight Engineer Jeff Williams got down to business. Their tasks this week included activating a new high-tech freezer; installing additional sound suppression devices; performing a functional check of a new oxygen generation system, which will become active next year; and preparing for the next spacewalk, set for just before 10 a.m. EDT on Aug. 3.

Discovery left behind about three tons of supplies, hardware and experiments as well as 175 gallons (660 liters) of water and 74 pounds (33 kilograms) of nitrogen, leaving the station in excellent condition to support the crew of three.

One of the most anticipated experiment racks, the Minus Eighty Laboratory Freezer for ISS, was activated. The freezer will allow biological and human research experiment samples to be stored until they are returned to Earth for evaluation.

The recent Discovery mission brought the new oxygen generation system and the freezer to the station. Status checks were performed this week on the newly installed oxygen system to prevent its internal valves from sticking over long periods of dormancy. Once it is activated, the device will augment the Russian Elektron oxygen-generation system in preparation for the further expansion of the station crew to six people.

The crew also began preparations for the next spacewalk. The spacewalk by Williams and Reiter will be conducted in U.S. spacesuits. The astronauts will deploy external experiments and prepare station truss components for future assembly work. Additional solar panels and electrical equipment will be delivered by the next two space shuttle missions, scheduled for late August and December. Spacewalk preparations included flushing cooling loops in the Quest airlock and the spacesuits and configuring airlock systems and tools. The astronauts also reviewed station robotic arm procedures.

The next station status report will be issued on Friday, July 28, or earlier if events warrant. For more about the crew's activities and station sighting opportunities, visit:

http://www.nasa.gov/station

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