(minor planet without comet characteristics)
The term asteroid is used for minor planets
in the asteroid belt, out to Jupiter's orbit.
It is also used more generally:
often to include minor planets closer to the Sun,
such as those that are near-Earth objects,
and sometimes to include centaurs,
i.e., minor planets further out.
The first discovered asteroids were
Ceres and Pallas in 1801, with the 15th discovered
in 1851. The term asteroids means star-like:
they appeared as points though they move
like planets. Now 100,000 have been identified,
many by computer, and the estimated population is millions.
A diameter of 10 meters is often (but not always)
used as the threshold between asteroid and meteoroid.
Ceres, the largest in the asteroid belt, is near 1,000 km in diameter,
the next largest with less than 600 km.
Asteroids are generally classified by type of orbit and by spectrum.
(minor planets,solar system,object type)
Agenzia Spaziale Italiana (ASI)
binary minor planet (BMP)
Campo Imperatore Near-Earth Object Survey (CINEOS)
corotation resonance (CR)
Catalina Sky Survey (CSS)
Kuiper Belt (K Belt)
late heavy bombardment (LHB)
Minor Planet Center (MPC)
near-Earth object (NEO)
Nearby Supernova Factory (NSNF)
Palomar Transient Factory (PTF)
Wide-field Infrared Survey Explorer (WISE)
Yarkovsky-O'Keefe-Radzievskii-Paddack effect (YORP)