For the second time in less than a month, the international space station's managers have switched the lineup for the outpost's next crew, this time citing compatibility and teamwork issues.
NASA announced Friday that astronaut Michael Fincke and cosmonaut Gennady Padalka will be launched aboard a Russian rocket to the space station in April. They have been training together for years.
Last month, NASA said Leroy Chiao would be on the next station flight, taking the place of a fellow astronaut pulled for undisclosed medical reasons, William McArthur Jr. The cosmonaut who had trained with McArthur, Valery Tokarev, was to go up with Chiao.
But on Friday, NASA acknowledged it would be better to keep the two-man teams intact and said Chiao would fly to the space station this fall with the cosmonaut with whom he has trained for years: Salizhan Sharipov.
Proposed by Russians
The Russian space program, which has decades of long-duration spaceflight experience, proposed the changes to NASA as well as representatives of the other countries taking part in the station. The decision is still subject to internal review, but NASA expects that to be completed soon.
Fincke, an Air Force lieutenant colonel, and Padalka, a colonel in the Russian Air Force, will replace the two men who have been living aboard the space station since October. They will be launched with Dutch astronaut Andre Kuipers, who will spend a week on the orbiting complex and return with the current residents.
The space station is limited to two residents until shuttle flights resume.
Mystery object sighted
Flight controllers, meanwhile, are puzzled by a small object that floated away from the space station following a thruster-firing test of a newly arrived Russian cargo ship.
On Thursday, astronaut Michael Foale reported seeing a 6- to 8-inch (15- to 20-centimeter) rectangular item pass over a solar panel of the crew living quarters and float away. He transmitted photographs of the object to Mission Control. The object has yet to be identified, but poses no safety hazard, officials said.