NEAR Shoemaker
The first spacecraft to orbit an asteroid, and the first to land on one.
Key facts
- Agency
- NASA (United States)
- Type of mission
- Asteroid orbiter and landing
- Target
- Asteroids Mathilde and Eros
- Launched
- 17 February 1996
- Status
- Ended 2001
NEAR, the Near Earth Asteroid Rendezvous mission, was the first spacecraft built to go into orbit around an asteroid. It was later renamed NEAR Shoemaker in honour of the geologist Eugene Shoemaker, who did much to show that impacts shape the planets.
Mathilde
On 27 June 1997 NEAR flew past 253 Mathilde, a dark asteroid about 53 kilometres across with craters almost as wide as the asteroid itself. Mathilde turned out to be only about 1.3 times as dense as water, so it must be full of empty space. It was early evidence that many asteroids are rubble piles: loose heaps of boulders held together by their own weak gravity.
Eros
After an engine burn failed in December 1998, the team rescued the mission and put NEAR into orbit around 433 Eros on 14 February 2000. Eros is a near-Earth asteroid shaped like a peanut, about 34 kilometres long. For a year NEAR mapped it in detail, finding boulders, smooth ponds of fine dust in crater floors and a surface battered by impacts.
Its X-ray and gamma-ray instruments measured the elements on the surface. The results looked like an ordinary chondrite, the most common kind of meteorite, though with less sulphur, probably lost from the surface over time.
The landing
Although it was never designed to land, NEAR was slowly lowered onto Eros on 12 February 2001 and kept sending data from the surface for about two weeks.
Key dates
| Date | What happened |
|---|---|
| 17 February 1996 | NEAR launched on a Delta II rocket. |
| 27 June 1997 | Flew past the dark asteroid 253 Mathilde. |
| 23 December 1998 | Flew past Eros after a failed engine burn delayed its arrival. |
| 14 February 2000 | Became the first spacecraft to orbit an asteroid, 433 Eros. |
| 12 February 2001 | Became the first spacecraft to land on an asteroid. |
| 28 February 2001 | Final contact with the spacecraft on Eros. |
See where this mission fits among all the others in the mission timeline.
Did you know?
NEAR touched down on Eros at about 1.5 to 1.8 metres per second, slower than walking pace.
Eros was the first near-Earth asteroid ever discovered, in 1898.