The launch of the space shuttle Discovery encountered another delay due to a fuel leak, space agency NASA reported. Space shuttle managers scrubbed Discovery's launch attempt due to a hydrogen leak at the Ground Umbilical Carrier Plate, or GUCP.
NASA officials said the next launch opportunity will come no earlier than Monday. The planned launch on Wednesday had already been delayed due to electrical issues stemming from a main engine computer controller.
The space agency reported that during the process of filling the external tank, the hydrogen leak was detected at the GUCP, an attachment point between the external tank and a 17-inch pipe that carries gaseous hydrogen safely away from Discovery to the flare stack, where it is burned off.
Discovery heads to the International Space Station (ISS) on its final mission, where it will be taking with it two key components-the Italian-built Permanent Multipurpose Module (PMM) and Express Logistics Carrier 4 (ELC4)-that will provide spare parts and storage capacity to the orbiting complex. Discovery also will deliver Robonaut 2, which will become the first humanoid robot in space.
Discovery will spend two days heading toward its rendezvous with the ISS. On the second day of the flight, the crew will perform the standard scan of the shuttle's thermal protection system using the orbiter boom sensor system attached to the end of Discovery's robotic arm. On the third day of the flight, Discovery will approach and dock with the space station. After the hatches are opened between the two spacecraft, both crews will begin working on transferring items between the two vehicles.
Flight day four will be focused on more transfer work, a NASA mission document outlines, while the main activity on the fifth day will be the spacewalk. The crew will install a power extension cable that could be used between the Unity and Tranquility ISS modules in the event Tranquility ever loses power. The NASA mission outline explained it needs to be installed before the PMM is secured in place because of access to the work area.
After STS-133, space shuttle Endeavour has one more flight on the manifest. The space agency noted Atlantis has the possibility of another flight, and it has to be ready for one regardless, as it would be the rescue vehicle if Endeavour were to need it. According to NASA files, Discovery has flown more missions than any other shuttle-more than any other spacecraft, in fact.
Discovery was NASA's third space shuttle orbiter to join the fleet at Kennedy Space Center in Florida. Construction of the shuttle began in August 1979 and was completed four years later. It is currently the oldest orbiter in service. The name comes from two Earth-bound exploring vessels, one used by Henry Hudson in the early 1600s to search for a northwest passage from the Atlantic to the Pacific, and the other one of two ships used by British explorer James Cook in the 1770s. Endeavour, the namesake of NASA's newest shuttle, was Cook's second ship.