| 3 July 1997
For Immediate Release
Deep Space Maneuver Retargets NEAR for Asteroid 433 Eros Encounter
The trajectory for the Near Earth Asteroid Rendezvous (NEAR) spacecraft was adjusted at 6:30 a.m. EDT, today, to target the spacecraft for an Earth swingby in 1998. An 11-minute firing of its bi-propellant engine slowed NEAR down by 269 meters per second (602 mph) to a current speed of about 18,244 meters per second (41,000 mph) and nudged the spacecraft about half a degree from its previous path. This maneuver puts NEAR on track for a close Earth flyby on Jan. 23, 1998, which will bend the spacecraft's trajectory into the orbital plane of asteroid 433 Eros.
"Everything went beautifully and we are now on target for a rendezvous with Eros in January 1999," says NEAR Mission Director Dr. Robert W. Farquhar of The Johns Hopkins University Applied Physics Laboratory (APL), Laurel, Md., where NEAR was designed and built. Spacecraft Systems Engineer Andrew G. Santo, also of the Applied Physics Laboratory, says, "The burn was performed so accurately that fuel that had been allocated for further correction can now be used during the orbital phase."
Today's maneuver was the first time the large thruster engine was fired. The next scheduled firing of the engine, Dec. 20, 1998, will mark the beginning of the Eros rendezvous sequence.
The flawless deep space maneuver continued the success story of the NEAR mission that began with its Feb. 17, 1996 launch from Cape Canaveral Air Station in Florida. On June 27, 1997, the spacecraft completed a flyby of asteroid 253 Mathilde, sending back spectacular images of a dark, battered carbon-rich rock believed to date from the beginning of the solar system. The flyby was the closest look at any asteroid to date and the first encounter with a C-type (carbon-based) asteroid. The Mathilde images were the first science return of NASA's Discovery Program. A radio science experiment measured for the first time the mass of an asteroid.
The NEAR mission, which will end Feb. 6, 2000, after a year-long study of Eros, will provide the first comprehensive study of a near-Earth asteroid. The mission has been managed by APL, where the Mission Operation and the Science Data centers are located. obtained on the Mathilde homepage at: http://sd-www.jhuapl.edu/NEAR/Mathilde. Photographs of the first Mathilde images, the NEAR spacecraft, and the NEAR launch are available upon request.