STS-119 Mission Preps Move Forward

At NASA's Kennedy Space Center in Florida, technicians installed space shuttle Discovery's gaseous hydrogen, or GH2, flow control valves Saturday. GH2 leak checks will be performed today. The GH2 valves are used to synchronize the gas pressure between the external fuel tank and the engines, creating an even flow. Final installation of the ordnance that will separate the shuttle from the mobile launcher platform at the time of liftoff is scheduled to take place late tonight. More

(Source: Space Daily - Feb 5)