253 Mathilde
Mathilde's orbit is eccentric, taking it to the farther reaches of the Main belt. Nonetheless, the orbit lies between the orbits of Mars and Jupiter; it does not cross the planetary orbits. It also has one of the slowest rotation periods of the known asteroids — most asteroids have a rotation period in the range of 2 – 24 hours. Because of the slow rotation rate, NEAR Shoemaker was only able to take pictures of 60% of the asteroid's surface. The slow rate of rotation may been accounted for by a moon orbiting the asteroid, but a search of the NEAR images revealed none bigger than 10 km in diameter out to 20 times the radius of 253 Mathilde.