Near Earth Asteroid Rendezvous

Communications with the NEAR spacecraft on the surface of Eros have ended, the last reception of signal was at 7:00 p.m. EST on 28 February. See the NASA press release for more details. A graph of the measurements of the gamma-ray spectrometer on the surface of Eros is available.

NEAR Shoemaker touched down on the surface of Eros at 3:01:52 p.m. EST (20:01:52 UT) Monday, 12 February and contact has been maintained. The spacecraft apparently came to rest with the camera and gamma-ray spectrometer pointing towards the ground and the solar panels and low gain antenna pointing generally towards the Earth and Sun. Ample power is available and data can be transmitted at about 10 bits/sec.

The spacecraft impacted at a velocity of about 1.5 to 1.8 meters/second (3.4 to 4.0 mph). The spacecraft obtained 69 high-resolution images before touchdown, the final image showing an area 6 meters across. NEAR was not designed as a lander, but survived the low-velocity, low-gravity impact, a signal continued after the "landing" using the omni-directional low-gain antenna as a beacon. The NEAR team will not be attempting to lift off from the asteroid again. For more, see the NASA Press Release

For details of the plans for the landing, see the 31 January NASA Press Release

Launch Date: 17 February 1996 - 20:43 UT (3:43 PM EST)
Launch Vehicle: Delta II
Planned on-orbit mass: 805 kg (includes 318 kg propellant)
Power System: Solar panels of 1800 W

The Near Earth Asteroid Rendezvous (NEAR) mission is the first of NASA's Discovery missions and the first mission ever to go into orbit around an asteroid. The spacecraft is equipped with an X-ray/gamma ray spectrometer, a near-infrared imaging spectrograph, a multispectral camera fitted with a CCD imaging detector, a laser altimeter, and a magnetometer. A radio science experiment will also be performed using the NEAR tracking system to estimate the gravity field of the asteroid. The ultimate goal of the mission was to rendezvous with and achieve orbit around the near Earth asteroid 433 Eros in January, 1999, and study the asteroid for approximately one year. A problem caused an abort of the first encounter burn and the mission had to be rescoped for a 23 December 1998 flyby of Eros and a later encounter and orbit on 14 February 2000. Eros is an S-class asteroid about 13 x 13 x 33 km in size. Studies will be made of the asteroid's size, shape, mass, magnetic field, composition, and surface and internal structure. Periapsis of the orbit will be as low as 24 km above the surface of the asteroid. Prior to its encounter with Eros NEAR flew within 1200 km of the C-class asteroid 253 Mathilde on 27 June 1997. It then flew by the Earth on 23 January 1998. The spacecraft has the shape of an octagonal prism, approximately 1.7 m on a side, with four solar panels and a fixed 1.5 m X-band high-gain radio antenna.

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