Asteroids - Classification and History

• Naming of Asteroids: An asteroid is named as follows:
1. First, an asteroid is given a provisional name indicating the year and month of its discovery. This name consists of the year, followed by a letter indicating the half month (e.g. A - January (1st half), B - January (2nd half)), followed by another letter indicating the sequence within the half month. So, 1997 BC would be the third asteroid discovered in the second half of January 1997.
2. When an asteroid's orbit is understood well enough that its poistion can be predicted, it is given a permanent number and name. Numbers are assigned sequentially. The name is arbitrarilly chosen by the discoverer. So, "243 Ida" is the 243rd asteroid to be numbered.

Summary of Major Asteroids

Num	Name	Radius (km)	Distance* (10^6km)	Albedo	Discoverer	Date
1	Ceres	457	413.9	0.10	G. Piazzi	1801
511	Davida	168	475.4	0.05	R. Dugan	1903
15	Eunomia	136	395.5	0.19	De Gasparis	1851
52	Europa	156	463.3	0.06	Goldschmidt	1858
10	Hygiea	215	470.3	0.08	De Gasparis	1849
704	Interamnia	167	458.1	0.06	V. Cerulli	1910
2	Pallas	261	414.5	0.14	H. Olbers	1802
16	Psyche	132	437.1	0.10	De Gasparis	1852
87	Sylvia	136	521.5	0.04	N. Pogson	1866
4	Vesta	262.5	353.4	0.38	H. Olbers	1807
951	Gaspra	17x10	205.0	0.20	Neujmin	1916
243	Ida	58x23	270.0	?	J. Palisa	29 Sep 1884

* Mean distance from the Sun.

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