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Near Shoemaker Earth Asteroid Rendezvous PDF

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Preview Near Shoemaker Earth Asteroid Rendezvous

NEAR Information http://nssdc.gsfc.nasa.gov/planetary/near.html NEAR Shoemaker Near Earth Asteroid Rendezvous See the NEAR Eros Descent Images 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 1 of 4 3/20/2006 8:01 PM NEAR Information http://nssdc.gsfc.nasa.gov/planetary/near.html 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. Preliminary (unvalidated) NEAR data sets can be found at the PDS Small Bodies Node Archive. Detailed NEAR Spacecraft and Mission Information Multispectral Imager (MSI) Near-Infrared Spectrograph (NIS) X-ray / Gamma-ray Spectrometer (XRS-GRS) Magnetometer (MAG) Laser Rangefinder (NLR) Radio Science (RS) and Gravimetry NEAR Eros Descent Images Images of Eros from orbit Images of Eros from the approach Science results from Eros Images of Mathilde Movie of the Mathilde Flyby On Friday, 27 June 1997 at 8:56 AM EDT NEAR flew within 1200 km of the C-class main-belt asteroid 253 Mathilde. The fly-by took place at 9.93 km/sec and included high-resolution (180 m/pixel) and color (seven filter) imaging. The images will be used to study the size, shape, surface features, colors and to search for any small moons of Mathilde. Results from the Flyby of 253 Mathilde Size estimated to be about 66 x 48 x 46 km Volume estimated at 78,000 cubic km (within ~15%) 17 Mass estimated at 10 kg (within ~3%) 3 Density estimated at 1.34 gram/cm Five craters found over 20 km across Largest crater 30 km wide, 6 km deep 2 of 4 3/20/2006 8:01 PM NEAR Information http://nssdc.gsfc.nasa.gov/planetary/near.html No satellites found Images taken during the Earth flyby Press Release on Earth Swingby - 23 January 1998 8 February 1999 NASA Press Release on the first Eros flyby. Images of Eros from the first flyby - 23 December 1998 Press release on the NEAR Eros rendezvous - 8 February 2000 Information on the NEAR Mathilde Flyby Information on the NEAR Eros Flyby Information on the NEAR Mission Trajectory Summary Information on NEAR Instruments Information on Comet Hyakutake NASA's Discovery Program Pre-encounter background on 253 Mathilde Pre-encounter background on 433 Eros NEAR project home page - Applied Physics Lab, JHU NEAR Mathilde encounter - Applied Physics Lab, JHU NEAR MSI-NIS instrument information - Cornell University NEAR XGRS instrument information - NASA/Goddard NEAR Orbital Elements - Cornell University NEAR Press Kit (ftp directory) - NASA Headquarters Low-cost innovation in spaceflight - The NEAR Shoemaker mission (3.3 Mb PDF) Images Images of Eros Images from the Earth Flyby Images from the Eros and Mathilde Flybys Movie of the Mathilde Flyby More Mathilde Images Gamma-Ray Spectrometer measurements on the surface of Eros Press Releases The End of an Asteroidal Adventure NEAR Shoemaker Phones Home for the Last Time - 28 February 2001 NEAR Shoemaker Makes Historic Touchdown on Asteroid Eros - 12 February 2001 NEAR Mission Completes Main Task, Now Will Go Where No Spacecraft Has Gone Before - 31 January 2001 Briefings and Live Feed Set for First Asteroid Touchdown - 25 January 2001 NEAR Shoemaker Observations Link Eros to Primordial Solar System - 30 May 2000 Mission was renamed NEAR Shoemaker in honor of Gene Shoemaker - 14 March 2000 NEAR poised for Valentine's Day Asteroid Encounter - 8 February 2000 3 of 4 3/20/2006 8:01 PM NEAR Information http://nssdc.gsfc.nasa.gov/planetary/near.html NEAR spacecraft reveals major features of Eros - 8 February 1999 NEAR spacecraft set for January 3 burn - 30 December 1998 Burn Abort and new Eros encounter plan - 22 December 1998 Briefing on upcoming Eros Encounter - 11 December 1998 NEAR Completes Earth Swingby - 23 January 1998 NEAR Earth Flyby and Sunglints - 15 January 1998 Gamma Ray Bursts observed by NEAR - 29 September 1997 Asteroid Mathilde reveals her dark past - 30 June 1997 NEAR observations of Comet Hyakutake planned for 24 March 1996 - March 1996 Detailed information on NEAR from the NSSDC Master Catalog Asteroid Fact Sheet NSSDC Asteroid Home Page Other NASA planetary missions NSSDC Planetary Home Page Author/Curator: Dr. David R. Williams, [email protected] NSSDC, Mail Code 690.1 NASA Goddard Space Flight Center Greenbelt, MD 20771 +1-301-286-1258 NASA Official: Ed Grayzeck, [email protected] Last Updated: 13 April 2005, DRW 4 of 4 3/20/2006 8:01 PM

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