[meteorite-list] Mars Rover Spirit Performs First Trajectory Maneuver

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:22:41 2004
Message-ID: <200306202302.QAA25192_at_zagami.jpl.nasa.gov>

Guy Webster (818) 354-0880
Nancy Lovato (818) 354-9382
Jet Propulsion Laboratory, Pasadena, Calif.

Donald Savage (202) 358-1547
NASA Headquarters, Washington, D.C.

News release: 2003-089

June 20, 2003

Mars Rover Spirit Mission Status

NASA's Spirit spacecraft, the first of twin Mars Exploration Rovers,
performed its first trajectory correction maneuver today.

Following commands from the Mars Exploration Rover flight team at
NASA's Jet Propulsion Laboratory, Pasadena, Calif., the spacecraft
first performed a calibration and check of its eight thrusters, then
fired the thrusters to fine-tune its flight path toward Mars.

The main burn had two components. Thrusters that accelerate the
rotating spacecraft along the direction of the rotation axis burned
steadily for about 28 minutes. Then, thrusters that accelerate the
spacecraft in a direction perpendicular to the rotation axis fired in
pulses timed to the spacecraft's rotation rate -- with 264 pulses
totaling about 22 minutes of burn time. The total maneuver increased
Spirit's speed by 14.3 meters per second (32 miles per hour).

At the end of the trajectory correction, Spirit performed an attitude
turn that adjusted its orientation in space to maintain the optimal
combination of facing its solar array toward the Sun and pointing its
low-gain antenna toward Earth. The spacecraft's next trajectory
correction maneuver is scheduled for Aug. 1 and its next attitude turn
for July 22.

All systems on the spacecraft are in good health. As of today at 6
a.m. Pacific Daylight Time, Spirit had traveled 27,390,000 kilometers
(17,020,000 miles) since launch on June 10, and was at a distance of
2,660,000 kilometers (1,653,000 miles) from Earth. It was traveling at
a speed of 32.22 kilometers per second (72,100 miles per hour)
relative to the Sun. Spirit will arrive at Mars on Jan. 4, 2004,
Universal Time (evening of Jan. 3, 2004, Eastern and Pacific times).
The rover will examine its landing area in Mars' Gusev Crater for
geological evidence about the history of water on Mars.

Spirit's twin, Opportunity, is being prepared at Cape Canaveral Air
Force Station, Florida, for a first launch opportunity at 12:27:31
a.m. June 26, Eastern Daylight Time (9:27:31 p.m. June 25, PDT).

JPL, a division of the California Institute of Technology, manages the
Mars Exploration Rover project for NASA's Office of Space Science,
Washington, D.C. Additional information about the project is
available from JPL at

http://mars.jpl.nasa.gov/mer

and from Cornell University, Ithaca, N.Y., at

http://athena.cornell.edu/ .

                                                                   
-end-
Received on Fri 20 Jun 2003 07:02:02 PM PDT