The Sun rising on asteroid Mathilde Click on image for artist's depiction of NEAR satellite and the asteroid Mathilde (96K GIF) Courtesy of NASA

Mathilde is a big asteroid. It is about 600 football fields across! This makes it the biggest asteroid a spacecraft has visited.

The NEAR spacecraft found five big craters on the surface of Mathilde. But it did not find water on the surface.

The Sun rising on asteroid Mathilde Click on image for artist's depiction of NEAR satellite and the asteroid Mathilde (96K GIF) Courtesy of NASA

Mathilde is a large asteroid. Its diameter was estimated to be 60 km. That is about 600 football fields across! This makes it the most massive asteroid yet to be visited by a spacecraft.

Mathilde is also unique because it has an extremely long period of rotation. In fact, scientists have said that it hardly moves! It takes 17.5 days for Mathilde to rotate just once on its own axis.

The NEAR spacecraft has found five craters over 20 km across (or 200 football fields across) on the surface of Mathilde. No evidence of water has been found.

The Sun rising on asteroid Mathilde Click on image for artist's depiction of NEAR satellite and the asteroid Mathilde (96K GIF) Courtesy of NASA

Mathilde is a large asteroid. Its diameter was estimated to be 60 km and its mass was estimated to be 1x10¹⁷ kg. This makes it the most massive asteroid yet to be visited by a spacecraft.

Mathilde is also unique because it has an extremely long period of rotation. In fact, scientists have said that it hardly moves! It takes 17.5 days for Mathilde to rotate just once on its own axis.

This asteroid is located in the Main Asteroid Belt. It is assumed that asteroids in the Main Asteroid Belt date from the beginning of the solar system. Mathilde's dark surface (reflectivity is less than 4%) is believed to consist of carbon-rich materials that have not been altered by planet-building processes. Understanding asteroids such as Mathilde will point towards the solar system's origin.

The NEAR spacecraft has found five craters over 20 km across on the surface of Mathilde. No satellites (moons) have been found yet. And no evidence of water has been detected.