By Phil Hylands
Astronautson the International Space Station spotted a leak of ammonia from the station’scooling system. The crew first saw the leak, in the vicinity of the P6 trusssection, around 1530 GMT on 9 May. The leak was in the same area as anotherleak that astronauts attempted to fix during an EVA on 1 November last year.
The leakwas from the cooling loop on the 2B power channel and due to the rate of theleakage the equipment that was powered from that channel were moved to the 2Apower channel on 10 May and the 2B power channel was shut down to preserve whatwas left of the ammonia coolant.
On 11 MayNASA Astronauts Chris Cassidy and Tom Marshburn started a five and a half hourEVA at 1244 GMT in an attempt to trace the source of the ammonia coolant leakon the P6 Truss. Even though they could find no trace of the leak they replacedthe pump controller box on the P6 Truss. Tests immediately after the pumpcontroller box was replaced showed no signs of leaking but the equipment willbe regularly checked in the future.