MESSENGER Shipped to Goddard for Prelaunch Tests

http://www.jhuapl.edu/newscenter/pre...003/031219.htm

December 19, 2003
For Immediate Release

Media Contact:
Michael Buckley
JHU Applied Physics Laboratory
Phone: (240) 228-7536 or (443) 778-7536
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MESSENGER Shipped to Goddard for Prelaunch Tests
NASA's First Mercury Orbiter Mission Marks a Milestone to May 2004 Launch

Less than six months from its scheduled launch to Mercury, MESSENGER
is set for the next round of tests to prepare it for the first
orbital study of the innermost planet.

MESSENGER was shipped today from the Johns Hopkins University
Applied Physics Laboratory (APL) in Laurel, Md. - where it was
designed and built - to the environmental testing facilities at
NASA's Goddard Space Flight Center in Greenbelt, Md. The 20-mile
delivery capped nearly four years of detailed design, assembly and
testing on one of the most complex spacecraft APL has ever built.
With features ranging from a lightweight composite structure and
miniaturized instruments to a heat-radiation system and protective
ceramic-fabric sunshade, MESSENGER is well equipped for a 5-year
cruise through the inner solar system and a yearlong study of
Mercury starting in July 2009.

"We're sending a spacecraft to orbit a planet where the sun is 11
times brighter than what we see on Earth and temperatures can climb
past 800 degrees Fahrenheit," says MESSENGER Project Manager David
G. Grant, of APL. "This is an incredible engineering and scientific
challenge that no one has ever tried before, and the team is doing
all it can on the ground to make sure MESSENGER succeeds at Mercury."

This week engineers finished the first of MESSENGER's "shake and
bake" tests, checking the spacecraft's structural strength atop
large vibration tables at APL. Over the next 10 weeks at Goddard the
team will check MESSENGER's balance and alignment; put it before
speakers that simulate the noise-induced vibrations of launch; and
seal it in a large thermal-vacuum chamber that duplicates the
extreme heat, cold and airless conditions of space. In March,
MESSENGER will be sent to Kennedy Space Center/Cape Canaveral Air
Force Station, Fla., and prepared for its May 2004 launch aboard a
Boeing Delta II rocket.

"Each part of the spacecraft has passed individual vibration and
environmental tests, and under tougher conditions than we expect
they will see at Mercury," says James C. Leary, MESSENGER mission
systems engineer at APL. "Now we're looking at MESSENGER as a whole
system. By the time it launches MESSENGER will have been thoroughly
tested."

Carrying seven scientific instruments - including a camera, laser
altimeter, magnetometer and several spectrometers - the solar-
powered MESSENGER will image Mercury globally for the first time. It
also will gather data on the composition and structure of Mercury's
crust, its geologic history, the nature of its thin atmosphere and
active magnetosphere, and the makeup of its core and polar
materials. While cruising to Mercury the spacecraft will fly past
the planet twice - in 2007 and 2008 - snapping pictures and
gathering data critical to planning the orbit study.

Sean C. Solomon of the Carnegie Institution of Washington leads
MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and
Ranging) as principal investigator; the Applied Physics Laboratory
manages the mission for NASA's Office of Space Science and will
operate the spacecraft. GenCorp Aerojet, Sacramento, Calif., and
Composite Optics Inc., San Diego, provided MESSENGER's propulsion
system and composite structure, respectively. APL, Goddard Space
Flight Center, University of Michigan, Ann Arbor, and University of
Colorado, Boulder, built the spacecraft's scientific instruments.

More information on MESSENGER's journey and science mission is
available at

http://messenger.jhuapl.edu.