|
----- Original Message -----
From: MESSENGER News
Sent: Friday, June 11, 2004 5:01 PM
Subject: On Again MESSENGER Mission
News
June 11,
2004
On
Again
Many members of the MESSENGER team are back in Florida, preparing the
spacecraft for the July 30 - August 13 launch opportunity.
In
this week's annotated Webcam image, MESSENGER is perched on the "elephant stand" while an overhead crane is
used to guide the nickel-hydrogen (Ni-H) flight battery into place. From this
vantage point you can see the outer row of 11 individual cells; they look like
upside down 1-liter soda bottles. The spacecraft has been
running on the spare battery since last November, except for a short period in
March when the flight battery was installed, then removed when the launch date was shifted to no earlier
than July 30. Similar to car batteries, spacecraft batteries have limited
lifetimes, so the flight battery is reserved until final launch preparations
commence.
Over the coming weeks MESSENGER's instruments will be powered up and
tested, its flight radiator and solar panels installed, insulation blankets
adjusted and full up simulations run. MESSENGER is scheduled to leave the Astrotech
processing facility for mating with its Delta
II launch vehicle on July 16.
This Week at the Cape MESSENGER is undergoing prelaunch testing at the Astrotech Space Operations facilities near Kennedy Space Center, Florida.
Autonomy testing of the spacecraft has been successfully completed. This verifies MESSENGER's ability to operate on its own when not in direct contact with Earth. Installation of thermal blankets continues. The solar arrays will be installed June 21, followed by release tests on June 23-24. Spacecraft propellant loading is scheduled for June 28-July 2. Spacecraft spin balance testing is planned for July 7 and mating to the upper stage booster will occur July 12.
The spacecraft will leave Astrotech for Cape Canaveral Air Force Station on July 16 and be mated to the Delta II rocket at Pad 17-B. Meanwhile, stacking of the launch vehicle on the pad is currently planned to begin on June 23. There are no technical issues or concerns with MESSENGER or the Delta II at this time. -- From a Kennedy Space Center news release
MESSENGER (MErcury Surface, Space ENvironment, GEochemistry,
and Ranging) is a scientific investigation of the planet Mercury, and the
first NASA mission designed to orbit the planet closest to the Sun. Dr. Sean C.
Solomon, of the Carnegie Institution of Washington, leads the
mission as principal investigator. The Johns Hopkins University Applied
Physics Laboratory in Laurel, Maryland, built and will operate the MESSENGER spacecraft
and manages the Discovery-class mission for NASA.
|
