Asteroid Data
Information on Selected Asteroids
Asteroid Diameter Mass Rotation Orbital Spectral Semimajor Orbital Orbital
Number and Name (km) (kg) Period Period Class Axis Eccentricity Inclination
1 Ceres 974 1e21 9.078 h 4.60 y C 2.767 AU 0.079 10.6 deg
2 Pallas 538 250e18 7.811 h 4.61 y U 2.771 AU 0.235 34.8 deg
3 Juno 268 20e18 7.21 h 4.36 y S 2.670 AU 0.256 13.0 deg
4 Vesta 526 300e18 5.342 h 3.63 y U 2.362 AU 0.088 7.1 deg
243 Ida 58 x 23 100e15 4.633 h 4.84 y S 2.862 AU 0.044 2.1 deg
253 Mathilde 61 200e15 418. h 4.31 y C 2.645 AU 0.266 6.7 deg
433 Eros 41 x 15 x 14 5e15 5.270 h 1.76 y S 1.458 AU 0.223 10.8 deg
951 Gaspra 19 x 12 x 11 10e15 7.042 h 3.29 y S 2.210 AU 0.146 5.1 deg
1566 Icarus 1.4 1e12 2.273 h 1.12 y U 1.078 AU 0.827 23.0 deg
1620 Geographos 2.0 4e12 5.222 h 1.39 y S 1.244 AU 0.335 13.3 deg
1862 Apollo 1.6 2e12 3.063 h 1.81 y S 1.486 AU 0.566 6.4 deg
2060 Chiron 180 4e18 5.9 h 50.7 y B 13.699 AU 0.383 6.9 deg
2062 Aten 0.9 S 0.97 AU 0.18
2530 Shipka 5.25 y 3.020 AU 0.123 10.1 deg
3840 Mimistrobell 3.38 y 2.250 AU 0.082 3.9 deg
4179 Toutatis 4.6 x 2.4 x 1.9 50e12 irregular 1.10 y S 0.921 AU 0.634 0.5 deg
4769 Castalia 1.8 x 0.8 500e9 0.41 y 0.550 AU 0.483 8.9 deg
Notes:
1 Ceres - The largest and first discovered asteroid, by G. Piazzi on January 1, 1801.
Ceres comprises nearly half the 2.3e21 kg estimated total mass of all the asteroids.
2 Pallas - The 2nd largest asteroid and second asteroid discovered, by H. Olbers in 1802.
3 Juno - The 3rd asteroid discovered, by K. Harding in 1804.
4 Vesta - The 3rd largest asteroid, Vesta appears to have a basaltic crust overlying
an olivine mantle, indicating differentiation has occurred.
Imaged by the Hubble Space Telescope in 1995.
243 Ida - Imaged by Galileo on August 28, 1993.
These images showed a small satellite, subsequently named Dactyl, in orbit about Ida.
253 Mathilde - Target of NEAR mission flyby on 27 June 1997 en route to 433 Eros.
433 Eros - Near-Earth asteroid scheduled to be studied by the NEAR mission,
which will be put into orbit about Eros in February 1999.
951 Gaspra - Imaged by Galileo on Oct. 29, 1991.
1566 Icarus - Highly eccentric Earth-crossing orbit.
1620 Geographos - Scheduled to be visited by Clementine before a computer malfunction
cut the mission short.
1862 Apollo - Earth-crossing asteroid.
2060 Chiron - Asteroid/Comet (95P/Chiron) in chaotic eccentric orbit near Saturn and Uranus.
First perihelion since 1945 will occur on 14 February, 1996.
Chiron is showing increased activity as it approaches the Sun.
2530 Shipka - Scheduled for October, 2008, flyby by the
Rosetta spacecraft on its way to Comet P/Wirtanen
3840 Mimistrobell - Scheduled for September, 2006, flyby by the
Rosetta spacecraft on its way to Comet P/Wirtanen
4179 Toutatis - Double object, probably in contact,
one 2.5 km and one 1.5 km diameter (estimated), imaged by Arecibo and Goldstone radar.
Next close approach to Earth of this object (0.0354 AU) will be on 30 November 1996.
4769 Castalia - Double-lobed near-Earth asteroid, each lobe about .75 km diameter.
Imaged by Arecibo radar.
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