SPACECRAFT AND EXPENDABLE VEHICLES STATUS REPORT<br />September 17, 2003<br /><br />George H. Diller<br />Kennedy Space Center<br />321/867-2468<br /> <br />MISSION: Gravity Probe B (GP-B)<br />LAUNCH VEHICLE: Delta II<br />LAUNCH PAD: SLC-2, Vandenberg Air Force Base<br />LAUNCH DATE: December 6, 2003<br />LAUNCH TIME: 5:52:02 p.m. PST <br /><br />Gravity Probe B is at NASA spacecraft processing hangar 1610 on North<br />Vandenberg Air Force Base. The pumping down of the dewar which is filled<br />with cryogenic liquid helium continues. This brings the environment within<br />the dewar to a near vacuum. It will then be refilled to the level necessary<br />to achieve and maintain superfluid conditions. <br /><br />The first stage of the Boeing Delta II was erected on Space Launch Complex 2<br />on Monday, Sept. 15, as scheduled. Mating of the second stage atop the<br />first stage is planned for tomorrow, Sept. 18. Attachment of the nine<br />strap-on solid rocket boosters in sets of three is scheduled for Oct. 6-8. <br /> <br />Gravity Probe B will be transported from the spacecraft hangar to Space<br />Launch Complex 2 on Nov. 18 and hoisted atop the second stage. The Delta II<br />fairing will be installed around the spacecraft on Nov. 24 as part of final<br />preparations for launch. Gravity Probe B arrived at Vandenberg Air Force<br />Base on July 11 from the Lockheed Martin plant in Sunnyvale, Calif. <br /><br />Gravity Probe B is a relativity experiment developed by NASA's Marshall<br />Space Flight Center, Stanford University and Lockheed Martin. The<br />spacecraft will test two extraordinary predictions of Albert Einstein's<br />general theory of relativity that he advanced in 1916. Gravity Probe B<br />consists of four sophisticated gyroscopes to be launched into a<br />400-mile-high orbit for a mission lasting 18 months.