[3] The primary scientific objective of NEAR was to return data on the bulk properties, composition, mineralogy, morphology, internal mass distribution, and magnetic field of Eros.

Secondary objectives include studies of regolith properties, interactions with the solar wind, possible current activity as indicated by dust or gas, and the asteroid spin state.

This data was used to help understand the characteristics of asteroids in general, their relationship to meteoroids and comets, and the conditions in the early Solar System.

A radio science experiment was also performed using the NEAR tracking system to estimate the gravity field of the asteroid.

NEAR was the first robotic space probe built by Johns Hopkins University's Applied Physics Laboratory (APL).

[5] The mission's primary goal was to study the near-Earth asteroid 433 Eros from orbit for approximately one year.

Some scientists claim that the mission's ultimate goal was to link Eros, an asteroidal body, to meteorites recovered on Earth.

Once this connection is established, meteorite material can be studied with large, complex, and evolving equipment, and the results can be extrapolated to bodies in space.

NEAR spent most of the cruise phase in a minimal activity "hibernation" state, which ended a few days before the flyby of the 61 km diameter asteroid 253 Mathilde.

[9] On July 3, 1997, NEAR executed the first major deep space maneuver, a two-part burn of the main 450 N thruster.

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.

This anomaly almost resulted in the loss of the spacecraft due to a lack of solar orientation and subsequent battery drain.

The camera took images of Eros, data were collected by the near IR spectrograph, and radio tracking was performed during the flyby.

A rendezvous maneuver was performed on January 3, 1999, involving a thruster burn to match NEAR's orbital speed to that of Eros.

The spacecraft then made a slow controlled descent to the surface of Eros, ending with a touchdown just to the south of the saddle-shaped feature Himeros on February 12, 2001, at approximately 20:01 UT (3:01 p.m. EST).

The decision to mount instruments on the body of the spacecraft rather than using booms resulted in the gamma-ray spectrometer needing to be shielded from noise generated by the craft.

[7] The NEAR mission was the first launch of NASA's Discovery Program, a series of small-scale spacecraft designed to proceed from development to flight in under three years for a cost of less than $150 million.

[2] The science payload includes:[17] This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration.