NEAR Shoemaker - Orbiter Space Flight Simulator 2010

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• published: 21 Feb 2016
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The Near Earth Asteroid Rendezvous – Shoemaker (NEAR Shoemaker), renamed after its 1996 launch in honor of planetary scientist Eugene Shoemaker, was a robotic space probe designed by the Johns Hopkins University Applied Physics Laboratory for NASA to study the near-Earth asteroid Eros. The NEAR mission was the first launch in NASA's Discovery Program. The spacecraft's mission was to rendezvous with and achieve orbit around the asteroid Eros in January, 1999, and study the asteroid for one year. However as it flew by the Earth on 23 January 1998, a problem caused an abort of the first encounter burn. The mission had to be rescoped for a later encounter, but NEAR successfully entered orbit around Eros on 14 February 2000 and ended the mission by gently landing on its surface on 12 February 2001. Launch date 20:43:27 UTC 1996-02-17 On 27 June 1997, NEAR flew by Mathilde within 1200 km at 12:56 UT at 9.93 km/s, July 3, 1997 NEAR executed the first major deep space maneuver, a two-part burn of the main 450 N thruster. This decreased the velocity by 279 m/s and lowered perihelion from 0.99 AU to 0.95 AU. The Earth gravity assist swingby occurred on January 23, 1998 at 7:23 UT. The closest approach was 540 km, altering the orbital inclination from 0.5 to 10.2 degrees, and the aphelion distance from 2.17 to 1.77 AU, nearly matching those of Eros. The first of four scheduled rendezvous burns was attempted on December 20, 1998 at 22:00 UT. The original mission plan called for the four burns to be followed by an orbit insertion burn on January 10, 1999, but the abort of the first burn and loss of communication made this impossible. A new plan was put into effect in which NEAR flew by Eros on December 23, 1998 at 18:41:23 UT at a speed of 965 m/s and a distance of 3827 km from the center of mass of Eros. A rendezvous maneuver was performed on January 3, 1999 involving a thruster burn to match NEAR's orbital speed to that of Eros. A hydrazine thruster burn took place on January 20 to fine-tune the trajectory. On August 12 a two-minute thruster burn slowed the spacecraft velocity relative to Eros to 300 km/h. Orbital insertion date 2000-02-14 at 433 Eros NEAR went into a 321 x 366 km elliptical orbit around Eros on February 14. The orbit was slowly decreased to a 35 km circular polar orbit by July 14. NEAR remained in this orbit for 10 days and then was backed out in stages to a 100 km circular orbit by September 5, 2000. Maneuvers in mid-October led to a flyby of Eros within 5.3 km of the surface at 07:00 UT on 26 October. Landed on 433 Eros 2001-02-12 At 7 pm EST on February 28, 2001 the last data signals were received from NEAR Shoemaker before it was shut down.