Posted: Wed, May 15, 2002, 8:28 PM ET (0028 GMT)
An oxygen generator on the International Space Station has malfunctioned and is undergoing repairs, forcing the crew to use a backup oxygen system. Elektron, a Russian unit that generates oxygen on the station, has had problems for about a week, and the unit was taken completely offline this week to allow the three-man Expedition Four crew to attempt to repair the unit. The most likely cause for the problem is the failure of an electronics box in the unit, which could be replaced with a spare already on the station. In the meantime the crew is using a backup system of oxygen "candles" that are burned to generate oxygen. Although there are no additional candles on the ground, NASA officials say there is up to three months' worth of candles on the station, and two Progress supply missions scheduled for launch later thus year could deliver additional oxygen. Station managers are also considering additional measures to conserve oxygen on the station, such as using oxygen from the shuttle, rather than the station, to pressurize the station's airlock during spacewalks scheduled for the upcoming STS-111 mission.
