Space Station Crew Discards Unmanned Cargo Ship

Two astronautscast off a spent cargo ship from the International Space Station (ISS) earlyFriday in move that will free up a docking port outside the orbital laboratory.

ISS Expedition12 commander Bill McArthur and flight engineer Valery Tokarev undocked theRussian-built Progress19 vehicle, an unmanned supply ship that sat at the aft end of the station'sZvezda service module since its Sept. 10 arrival.

McArthurand Tokarev crammed Progress 19 with trash, unneeded equipment and clothes andsiphoned its last remaining supplies of water and oxygen before undocking it at5:06:10 EST (1006:10 GMT) Friday. After a brief engine firing to fly clear ofthe space station, the Progress 19 vehicle began its Earthward descent and isexpected to burn up in the planet's atmosphere.

Someparts of the spacecraft may survive atmospheric reentry and plummet into thePacific Ocean about 1,864 miles (3,000 kilometers) east of Wellington, NewZealand, Russian ISS mission control spokesperson Valery Lyndin told the InterfaxNews Agency.

Progress 19'sdeparture clears the way for a brief spaceflight on March 20 by the Expedition12 astronauts. McArthur and Tokarev are expected to relocatetheir Soyuz TMA-7 vehicle from its berth at the Earth-facing port on thestation's Zarya control module in anticipation of their relief crew's arrival.

In a dailyISS update, NASA spokesperson Rob Navias said the "Progress and Soyuz shell game"clears the Zarya docking port for Expedition13 commander Pavel Vinogradov, flight engineer Jeffrey Williams and MarcosPontes - Brazil's first astronaut. Pontes and the Expedition 13 crew willlaunch from Baikonur Cosmodrome in Kazakhstan on March 29 at 9:30 p.m. EST (0230March 30 GMT) and dock the station two days later.

Duringtheir short spaceflight, McArthur and Tokarev will each don their Russian-builtSokol spacesuits, climb inside their Soyuz vehicle and undock from the ISS at 1:45a.m. EST (0645 GMT). By 2:22 a.m. EST (0722 GMT), they should arrive at thestation's Zvezda berth, NASA officials said.

McArthurand Tokarev are less than six weeks away from completing their six-monthmission aboard the ISS. The two astronauts arrived aboard the station inOctober 2005 and are expected to return to Earth with Pontes in early April.

WhileProgress 19 has left the ISS, another unmanned cargo ship remains parked at thestation's Pirs docking compartment. That resupply ship, Progress20, arrived at the ISS on Dec. 23.

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