Space Station Astronauts Prepare for Crew Change

Twoastronauts aboard the International Space Station (ISS) are spending their lastweeks in orbit as they await the upcoming launch of their relief crew and onepaying space tourist.

ISSExpedition 11 commander Sergei Krikalev and flight engineer John Phillips areset to return to Earth on Oct. 10 after handing control over to theirreplacements - Expedition 12'sBill McArthur and Valery Tokarev. The landing will end a six-month mission thatsaw one spacewalk, a new spaceflight record and the first NASA shuttle flight to the ISS sinceNovember 2002.

"This crewhas done very well," said James Locke, NASA's lead flight surgeon forExpedition 11, during a press briefing at NASA's Johnson Space Center (JSC) inHouston, Texas. "In some cases, [ISS astronauts] are actually in better shape thanwhen they left, and I suspect that's the case here."

In orbit, astronautssometimes have more time to exercise, which prevents excessive bone and muscleloss in microgravity, than during flight training, Locke said.

Meanwhile,a fresh SoyuzTMA-7 spacecraft is just over one day away from launching the Expedition 12crew into space with U.S. scientist GregoryOlsen, a fare-paying participant who is paying about $20 million for theorbital ride. The space-bound trio will launch on Sept. 30 at 11:54 p.m. EDT(0354 Oct. 1) GMT.

A jobwell done

NASA ISSofficials said that Krikalev and Phillips have had a great mission despite someuncertaintyearly in the flight as to when Discovery would arrive at the station.

Slatedto arrive in mid-May - about one month after Krikalev and Phillips arrivedat the space station - Discovery dockedat the ISS in late July, delivering six tons of vital spare parts, supplies andscience equipment to the orbital platform.

Discovery'sISS flight marked NASA's first shuttle flight since the 2003 loss of Columbia, which disintegratedduring reentry on Feb. 1, 2003, killing its crew. Wing damage from externaltank foam debris at launch was cited as the accident's cause.

Krikalevand Phillips also anticipated a secondshuttle flight to the ISS during their mission - STS-121 aboard Atlantis -which was slated to deliver more supplies and European Space Agency astronaut Thomas Reiterto the ISS. Reiter's arrival would have brought the ISS back up to athree-person crew complement, but was delayeddue launch debrisconcerns raised during Discovery's liftoff. He is slated to fly aboardDiscovery - now flying STS-121 - sometime in 2006.

But despitethe delays, Krikalev and Phillips managed to complete all of their plannedscience tasks, including the completion of a long-running ultrasoundexperiment that tested astronauts' abilities to scan crewmates with guidancefrom ground-based scientists, NASA officials said. The experiment will aid remote medicine practiceshere on Earth, they added.

"John performedthe first-ever voice-only scan, where the ground couldn't see what he wasseeing," explained ISS program scientist Don Thomas during the briefing. "Itwas an extremely difficult thing to do."

Krikalevand Phillips also conducted one spacewalkto retrieve experiments on the station's exterior and outfit the laboratorywith antennas to be used by an unmanned European cargo ship expected next year.

Krikalevcontinues to set a new record for total time spent in space during hiscosmonaut career after breaking the record on Aug. 16. To date, he hasspent 791 total days and counting in Earth orbit.

Reliefcrew awaits launch

While theExpedition 11 crew prepares for landing, the Expedition 12 crew and Olsen arecounting down toward launch.

McArthur, aNASA astronaut, will command Expedition 12 with cosmonaut Valery Tokarev of theRussian Federal Space Agency serving as flight engineer. With the delayedlaunch of STS-121 and Reiter - who would have stayed on for Expedition 12 - McArthurand Tokarev are one astronaut short, forcing increment planners to shuffle thecrew's task plans for the mission.

"The majorchallenges we're facing now is crew time," Expedition 12 increment manager PeteHasbrook. "We've got a lot do with fewer crew...we're going to revise ourpriorities."

McArthurand Tokarev are scheduled to perform at least one spacewalk in November clad inU.S. spacesuits, and another in December using Russian Orlan spacesuits,mission managers said. A third spacewalk in February 2006 may also be performeddepending on time, they added.

Meanwhile,the two astronauts have 13 primary science programs for their flight, thoughsome studies - such as the Foot experiment to compare differences in the body'suse of its lower extremities in orbit and on Earth - depends on when thehardware arrives at the ISS. Some science hardware was slated to arrive withSTS-121, mission managers said.

NASA'sshuttle flight delays also complicated plans for McArthur's return to Earth.

Theastronaut initially planned toreturn to Earth aboard a NASA space shuttle in May 2006, after 213 days inorbit, about one month after Tokarev left the ISS aboard their Soyuz TMA-7spacecraft. With the launch date of NASA next shuttle far from certain, U.S.and Russian ISS officials agreed to return McArthur via Soyuz with Tokarev.

"Thecurrent plan shows him coming home on the [Soyuz] in the spring," Hasbrooksaid.

Under abilateral agreement with Russia, Soyuz TMA-7 is the last Soyuz with a seatfor a NASA astronaut available at no charge, though the space agency would havebeen unable to procure more flights due to the Iran Nonproliferation Act of2000. The act bars the U.S. purchase of Russian human spaceflight hardware solong as Russia continues to aid Iran's pursuit of nuclear and advanced weaponstechnology.

Last week, theU.S. Senate approveda bill that would clear NASA to purchase additional Soyuz flights in thefuture.

Spacetourist set to fly

Riding upto the ISS with the Expedition 12 crew Friday is an eager Gregory Olsen, a U.S.scientist and entrepreneur who is paying $20 million to visit the space station.

Olsen'strip, brokered with the Russian Federal Space Agency by the space tourism firm Space Adventures, will make him thethird fare-paying visitor to the ISS after the 2002 flight of MarkShuttleworth and 2001 launch of DennisTito. Space Adventures also brokered the flights of Shuttleworth and Titoas well.

"He's freeto go anywhere on the space station that he'd like," said Kirk Shireman, NASA'sISS operations and integration manager, of Olsen. "He's been trained on thebasic U.S. systems so he'll know what to do in an emergency if he's in the U.S.segment."

Shiremanadded that Olsen will also have access to the station's telephone and e-mailservices as well.

Olsen,founder of the Princeton, New Jersey-based Sensors Unlimited, Inc., will spendabout one week aboard the ISS before returning to Earth with the Expedition 11crew. He will perform a trio of experimentsfor the European Space Agency (ESA) and observe the Earth, NASA officials said.

Expedition12 lead flight director Sally Davis said Olsen is trained and ready for hisflight.

"He'slooking very much forward to being onboard station," Davis said, adding thatOlsen is well-versed in alarm and egress procedures. "In a phrase, I'd say hegets it."

• Gregory Olsen: Third Space Tourist Aims for Orbit
• Complete Coverage: ISS Expedition 11
• Complete Coverage: ISS Expedition 12