Asteroid
The dwarf planet Ceres is by far the largest asteroid, with a diameter of . The next largest are 4 Vesta and 2 Pallas, both with diameters of just over . Vesta is the only main-belt asteroid that can, on occasion, be visible to the naked eye. On some rare occasions, a near-Earth asteroid may briefly become visible without technical aid; see 99942 Apophis.
(4953) 1990 MU
(4953) 1990 MU is a large Earth-crossing asteroid (ECA) belonging to the Apollo family of asteroids which also cross the orbits of Mars and Venus. At approximately 3 km in diameter, it is one of the largest known ECAs. is the asteroid's temporary discovery name. It has now been assigned a permanent number from the Minor Planet Center (4953) indicating that its orbit has been confirmed, but has not (at least so far) been assigned a name. Only a small fraction of asteroids have been named.