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Mission Timeline
The NEAR mission is the first to orbit a small body, and much remains unknown. Because the mission is exploring new frontiers, NEAR operations must remain fluid to respond to evolving scientific findings. Therefore, dates, altitudes and event sequences listed here may change as the mission unfolds. Check the news and science sections of the NEAR Web site (http://near.jhuapl.edu) for the most up-to-date information.
- Feb. 17, 1996
NEAR successfully launches from Cape Canaveral on a Delta-2 rocket. Feb. 18, 1997 NEAR establishes record for the greatest distance from the sun for a solar-powered spacecraft (203 million miles/327 million kilometers). June 27, 1997 In a flyby of asteroid Mathilde, NEAR comes within 753 miles (1,212 kilometers) of the asteroid. Jan. 23, 1998 An Earth swingby puts NEAR on course toward asteroid 433 Eros. At its closest point to Earth, the spacecraft passes about 335 miles (540 kilometers) above Ahvaz in southwestern Iran. April 1, 1998 NEAR sets the record as the most distant manmade object detected by optical means when an amateur astronomer in New South Wales, Australia, spots the spacecraft at a distance of 20.91 million miles (33.65 million kilometers) from Earth. The previous record was the 1992 sighting of the Galileo spacecraft at a distance of 5 million miles (8.06 million kilometers) from Earth. Dec. 20, 1998 NEAR's initial Eros rendezvous maneuver aborts moments after thruster firing starts. Contact with Mission Operations is regained after 27 hours of silence, revealing a healthy spacecraft that lost 64 pounds (29 kilograms) of propellant during its attempt to recover communications. Dec. 23, 1998 NEAR comes within 2,378 miles (3,827 kilometers) of Eros at 2,158 miles per hour (965 meters per second). Jan. 3, 1999 Large bipropellant thruster burn executed to close the gap between NEAR's orbital speed and that of Eros. Jan. 20, 1999 Hydrazine thruster burn completed to fine-tune the spacecraft's trajectory and speed. Aug. 12, 1999 Last major trajectory correction completed with 2-minute burn of the hydrazine engine, slowing the spacecraft to 188 mph relative to Eros. Feb. 3 and 8, 2000 Two-part rendezvous maneuver precisely targets NEAR for initial approach to Eros. Feb. 13, 2000 Zero-phase measurements occur using the Near-Infrared Spectrometer as the spacecraft flies between Eros' northern hemisphere and the sun. (You are looking at zero-phase when the sun is directly overhead and casting no shadows.) Feb. 14, 2000 NEAR enters an orbit 207 miles (333 kilometers) from the center of Eros, and the yearlong encounter begins. Feb. 14 to April 30, 2000 High-orbit phase. NEAR orbits Eros at distances decreasing from 311 to 31 miles (500 to 50 kilometers) from the center of the asteroid. March 10, 2000 NEAR spacecraft descends to 125-mile (200-kilometer) orbit. March 14, 2000 NASA renames the spacecraft NEAR Shoemaker to honor the late Dr. Eugene M. Shoemaker, a geologist who influenced decades of research on the role of asteroids and comets in shaping the planets. April 11, 2000 NEAR Shoemaker reaches orbit of 62 miles (100 kilometers). April 30, 2000 NEAR Shoemaker arrives at a polar orbit of 31 miles (50 kilometers) from Eros, its prime scientific vantage point. April 30 - Aug. 27, 2000 Low-orbit phase. NEAR Shoemaker travels in nearly circular orbits ranging from 31 miles (50 kilometers) to 21 miles (35 kilometers) from Eros. Among key scientific activities, the X-Ray/Gamma-Ray Spectrometer measures the asteroid's element abundances, which will help determine the relationship between meteorites and asteroids. June 25, 2000 For the first time since NEAR Shoemaker arrived at Eros, the sun illuminates all of Eros (excluding deep polar craters). Sunlight shines directly over Eros' equator as the sub-solar point moves south. Aug. 27 - Dec. 27, 2000 NEAR Shoemaker travels in orbits of 31 to 125 miles (50 to 200 kilometers) from Eros. During this period, the retrograde orbit shifts from nearly polar to nearly equatorial, where the spacecraft travels opposite the direction of Eros' spin. Oct. 25-26, 2000 NEAR Shoemaker makes a low-altitude pass over a section of Eros, coming within 4 miles (about 6 kilometers) of the asteroid's surface. Dec. 27, 2000 Low-altitude operations resume as the spacecraft passes within 21 miles (35 kilometers) or closer during each orbit. February 2001 Mission ends.
