253 Mathilde

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Template:Minor Planet 253 Mathilde is a Main belt asteroid that was visited by the NEAR Shoemaker spacecraft on its way to asteroid 433 Eros. It is a primitive C-type asteroid, the first such asteroid to be visited by a spacecraft. It is also currently the largest asteroid to be visited by a spacecraft.

Image:253 Mathilde small.jpg

Mathilde is very dark, blacker than coal, and is thought to share the same composition as carbonaceous chondrite meteorites. The density measured by NEAR Shoemaker, 1,300 kg/m³ was less than half that of a typical carbonaceous chondrite; this may indicate that the asteroid is very loosely packed rubble pile. (Yeomans, et al, 1997) The same is true of several C-type asteroid studied through ground-based telescopes equipped with Adaptive Optics system (45 Eugenia, 90 Antiope, 87 Sylvia, 121 Hermione)

The asteroid is marked by a number of extremely large, extremely clear craters; several are wider than the asteroid's average radius. No differences in brightness or colour were visible so the asteroid's interior must be very homogeneous.

Mathilde's orbit is eccentric, taking it to the outer reaches of the Main belt. It also has one of the slowest rotation periods of the known asteroids. Because of that NEAR Shoemaker was not able to photograph all of the asteroid's surface.

It was discovered by Johann Palisa on November 12, 1885 in Vienna.

Mathilde is believed to be named after the wife of astronomer Moritz Loewy.

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