[meteorite-list] NASA's Mars Orbiter Makes Successful Course Correction

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue Aug 30 11:07:05 2005
Message-ID: <200508301505.j7UF5oJ01914_at_zagami.jpl.nasa.gov>

Dolores Beasley
Headquarters, Washington August 30, 2005
(Phone: 202/358-1753)

Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone: 818/354-6278)

RELEASE: 05-236

NASA'S MARS ORBITER MAKES SUCCESSFUL COURSE CORRECTION

NASA's Mars Reconnaissance Orbiter (MRO) successfully tested its
main engines by making a successful trajectory adjustment for
reaching the red planet on March 10, 2006.

The spacecraft fired all six main thrusters for 15 seconds on
Saturday. The engine burn followed a 30-second burn of six smaller
thrusters, which settled propellant in the craft's fuel tank for
smoother flow. The spacecraft's orientation was adjusted prior to
the burns to point the engines in the proper direction for the
maneuver. The MRO returned to the regular cruise-phase attitude
after the trajectory adjustment.

"This maneuver accomplished two goals at once," said Mars
Reconnaissance Orbiter Deputy Mission Manager Dan Johnston of
NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif. "It
adjusted our trajectory toward our Mars target point, and it gave
us a valuable checkout of the orbit-insertion engines." The
target point is 395 kilometers (245 miles) above the surface of
Mars.

Initial analysis of navigational data indicates this first flight
path correction successfully changed the spacecraft's velocity by
the intended 7.8 meters per second (17.4 mph). MRO's velocity
relative to the sun is 32,856 meters per second (73,497 mph).

The six main engines won't be used again until the craft arrives
at Mars. The next burn will last about 25 minutes. It will slow
the MRO enough for the planet's gravity to capture the spacecraft
into orbit. Each main engine produces approximately 38 pounds of
thrust. The three remaining opportunities scheduled for
fine-tuning the trajectory before March will use smaller engines.
Each smaller engine produces approximately five pounds of thrust.

"We intentionally designed the initial trajectory after launch
with a bias in it, so this first correction maneuver would be
large enough to let us use the main engines," Johnston said.

The next milestone for the MRO mission is today. MRO will turn on
its instruments to check their condition. The spacecraft was
launched Aug. 12, and it is in excellent health. MRO has traveled
approximately 6 million kilometers (3.7 million miles) since launch.
It has 95.9 million kilometers (59.6 million miles) still to fly
before reaching Mars.

The MRO mission will examine Mars in unprecedented detail from low
orbit. Mission science objectives include studying water
distribution, including ice, vapor or liquid; geologic features
and minerals. It will also support future missions to Mars by
examining potential landing sites and by providing a relay for
communications back to Earth.

The mission is managed by JPL, a division of the California
Institute of Technology, Pasadena, for the NASA Science Mission
Directorate. Lockheed Martin Space Systems, Denver, is the prime
contractor for the project and built the spacecraft.

For information about the MRO on the Web, visit:

http://www.nasa.gov/mro

For information about NASA and agency programs on the Web, visit:

http://www.nasa.gov/home/index.html

-end-
Received on Tue 30 Aug 2005 11:05:49 AM PDT