Start the countdown clock at one year:
the effort to assemble and test the MErcury Surface, Space ENvironment,
GEochemistry, and Ranging (MESSENGER) spacecraft, set to embark
next March on an historic voyage to the innermost planet, is well
On Feb. 3, MESSENGER's integrated propulsion
system and structure arrived at The Johns Hopkins University Applied
Physics Laboratory (APL) in Laurel, Md., which is building the remainder
of the spacecraft and manages the Discovery-class mission for NASA.
Having already completed the first round of vibration tests and
a thermal "bake out" to clean the structure, the MESSENGER
team will start installing electronic components on the craft in
frame for MESSENGER's signature sunshade - which will protect the
craft and its instruments from the intense heat at Mercury - is
due to arrive this week from GenCorp Aerojet. Layers of ceramic
fabric will be added to the frame at APL over the next two months.
MESSENGER's seven scientific
instruments - being provided by APL, NASA's Goddard Space Flight
Center in Greenbelt, Md., the University of Colorado, Boulder, and
the University of Michigan, Ann Arbor - are expected to arrive later
this spring. Integration and testing will continue at APL through
early September, and then MESSENGER heads to Goddard Space Flight
Center for additional prelaunch space-environment tests.
In early January, MESSENGER is scheduled to
leave Goddard for Kennedy Space Center, Fla., in final preparation
for its March 2004 launch aboard a Boeing Delta II rocket.
After launch and a 5-year journey through the
inner solar system, MESSENGER will orbit Mercury for one Earth year,
providing the first images of the entire planet and collecting information
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 mysterious 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 that begins in April 2009. MESSENGER
will also fly by Venus in 2004 and 2006.
Click here for more
information on MESSENGER's scientific mission.