MESSENGER Status Report

July 21, 2004

MESSENGER, riding atop its spacecraft transporter, departed the Astrotech Space Operations facilities in Titusville, Florida, at 12:27 a.m. today. It arrived at Pad 17-B on Cape Canaveral Air Force Station at 4:30 a.m. and was hoisted atop the Boeing Delta II rocket at 6:20 a.m. The Flight Program Verification, an integrated test of the spacecraft/launch vehicle combination and the last major test before launch, is scheduled to occur on July 24.

The spacecraft was mated to the Delta third stage, or upper stage, on July 12 at Astrotech.

Meanwhile, the stacking of the Boeing Delta II launch vehicle on Pad 17-B began on June 30 with the hoisting of the first stage atop the launcher. Attachment of the nine strap-on solid rocket boosters in sets of three was completed July 6. The second stage was hoisted into position atop the first stage on July 8.

The first "power on" testing was completed on July 12. A vehicle control check was performed on July 14. This test procedure qualifies the first and second stage steering systems. A Simulated Flight (SimFlight) or flight test of the launch vehicle electrical and mechanical systems was completed on July 15. The first stage leak check, or LOX leak check, occurred on July 16 with the loading aboard of liquid oxygen. This test also exercises the first stage propulsion team using a procedure similar to that which will be during the countdown on launch day. On Monday, July 19, the first stage fuel system was then qualified by loading RP-1, a highly refined kerosene fuel.

There are no technical issues or concerns with MESSENGER or the Boeing Delta II at this time. MESSENGER's launch period opens at 2:16:11 a.m. (EDT) on August 2, with daily 12-second launch opportunities available through August 14.

(From a Kennedy Space Center news release)