NASA's space shuttle Atlantis is loaded and ready for takeoff from the Kennedy Space Center in Florida this afternoon. They're scheduled to deliver equipment, including two gyroscopes, to the International Space Station . NASA is focused on building up a reserve of spare parts on the space station in anticipation of the retirement of the space shuttle fleet. "You'll see this theme in some of the flights that are going to come after ours as well," said Brian Smith, the lead space station flight director for the mission, in a statement. "This flight is all about spares. The six-man crew is set to launch at 2:28 p.m. EST today. Basically, we're getting them up there while we still can." The equipment is considered highly critical to the operation of the space station, according to NASA. At this point, there are only six flights left for the space shuttles before they're scheduled to be retired.
Since this is the first mission to deliver what scientists hope will turn into a trove of spare parts, they're taking up the most important pieces. The equipment that needs to go up is being delivered in order of highest priority. The astronauts are expected to make three space walks during the 11-day mission. The equipment being delivered includes two pump modules, two gyroscopes, two nitrogen tank assemblies, an ammonia tank assembly and a high-pressure gas tank. The astronauts will work with the robotic arms onboard the shuttle and the space station to move two platforms loaded with spare parts out of the shuttle's cargo bay to where they'll be attached on either side of the station's truss or backbone. Parts going up for the robotic systems onboard the station include a latching end effector for the station's robotic arm and a trailing umbilical system reel assembly for the railroad cart that allows the arm to move along the station's truss system.
As of 10:30 a.m., a NASA inspection team was studying the exterior of Atlantis , its solid rocket boosters and the external tank for ice or other debris. NASA reports there are 27,250 pounds worth of parts being delivered in this mission. Space agency crews also have loaded the shuttle's external tank with about 535,000 gallons of liquid hydrogen and liquid oxygen, which will power the shuttle's three main engines during launch. NASA forecasts a 70% chance of weather good enough for a launch this afternoon.