The next scheduled commander of the international space station has been bumped from his flight because of an undisclosed medical issue, NASA announced Monday.
Astronaut William McArthur will not replace Michael Foale as the station’s skipper this spring because of a temporary medical problem that disqualifies him for a six-month mission, NASA said. Officials refused to elaborate, citing medical privacy.
McArthur will be replaced by his backup, Leroy Chiao, who was a crewmate of McArthur's on a shuttle flight to the space station in 2000. Chiao has been training alongside McArthur for months.
Chiao will join Russian cosmonaut Valery Tokarev on the Expedition 9 mission. In April, Chiao, Tokarev and Dutch astronaut Andre Kuipers are to travel to the station in a Russian Soyuz craft launched from Kazakhstan's Baikonur Cosmodrome. A week later, Kuipers will return to Earth with Foale and his Expedition 8 crewmate, Russia's Alexander Kaleri, in the Soyuz currently docked to the station.
"This is a temporary medical issue for Bill," Astronaut Office Chief Kent Rominger said in NASA's announcement of the change. "Because we are very cautious in our approach to crew health, we train backups for this kind of situation. We plan to assign Bill to another flight in the near future."
McArthur was quoted as saying he was disappointed that he wouldn't fly this spring, "but I understand the necessity of the medical criteria that are in place for long-duration space flight."
"I know that Leroy will ensure all of the Expedition 9 objectives are met, and I look forward to flying soon on another space station mission," he said.
The space station is limited to two long-term residents until NASA’s shuttles are flying again. The fleet was grounded following the Columbia tragedy nearly a year ago.
In 2002, another astronaut had to be pulled from a space station mission because of concern over the amount of radiation he would receive on such a long flight. His backup filled in.