Messenger Begins Orbit Around Mercury

This bit of space news crossed my desk today...

MESSENGER Begins Historic Orbit around Mercury 

At 9:10 p.m. EDT, engineers in the MESSENGER Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., received the anticipated radiometric signals confirming nominal burn shutdown and successful insertion of the MESSENGER probe into orbit around the planet Mercury. 

 The spacecraft rotated back to the Earth by 9:45 p.m. EDT, and started
transmitting data.  Upon review of these data, the engineering and
operations teams confirmed that the burn executed nominally with all
subsystems reporting a clean burn and no logged errors.

 

MESSENGER?s main thruster fired for approximately 15 minutes at 8:45
p.m.,
slowing the spacecraft by 1,929 miles per hour (862 meters per second)
and
easing it into the planned eccentric orbit about Mercury. The rendezvous
took place about 96 million miles (155 million kilometers) from Earth.

 

?Achieving Mercury orbit was by far the biggest milestone since
MESSENGER
was launched more than six and a half years ago,? says MESSENGER Project
Manager Peter Bedini, of APL. ?This accomplishment is the fruit of a
tremendous amount of labor on the part of the navigation,
guidance-and-control, and mission operations teams, who shepherded the
spacecraft through its 4.9-billion-mile [7.9-billion-kilometer]
journey.?

 

For the next several weeks, APL engineers will be focused on ensuring
that
MESSENGER?s systems are all working well in Mercury?s harsh thermal
environment. Starting on March 23, the instruments will be turned on and
checked out, and on April 4 the primary science phase of the mission
will
begin.

 

?Despite its proximity to Earth, the planet Mercury has for decades been
comparatively unexplored,? adds MESSENGER Principal Investigator Sean
Solomon, of the Carnegie Institution of Washington. ?For the first time
in
history, a scientific observatory is in orbit about our solar system?s
innermost planet.  Mercury?s secrets, and the implications they hold for
the
formation and evolution of Earth-like planets, are about to be
revealed.?

 

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MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging)
is
a NASA-sponsored scientific investigation of the planet Mercury and the
first space mission designed to orbit the planet closest to the Sun. The
MESSENGER spacecraft launched on August 3, 2004, and after flybys of
Earth,
Venus, and Mercury will start a yearlong study of its target planet in
March
2011. Dr. Sean C. Solomon, of the Carnegie Institution of Washington,
leads
the mission as Principal Investigator. The Johns Hopkins University
Applied
Physics Laboratory built and operates the MESSENGER spacecraft and
manages
this Discovery-class mission for NASA.