Asteroid Fact Sheet
Information on Selected Asteroids
The image above is a false color view of the asteroid 951 Gaspra taken by the
Galileo spacecraft. Below is a table of information on selected asteroids,
and at the bottom of the page are comments on the asteroids. All of the
values for mass and many of the diameter values are only rough estimates.
Asteroid Diameter ~Mass Rotation Orbital Spectral Semimajor Orbital Orbital Number
Number and Name (km) 1015 kg Period Period Class Axis Eccentricity Inclination and Name
--------------- -------- ------- -------- ------- -------- --------- ------------ ----------- --------
1 Ceres 960 x 932 870,000 9.075 hrs 4.60 yrs C 2.767 AU 0.0789 10.58 deg 1 Ceres
2 Pallas 570 x 525 x 482 318,000 7.811 hrs 4.61 yrs U 2.774 AU 0.2299 34.84 deg 2 Pallas
3 Juno 240 20,000 7.210 hrs 4.36 yrs S 2.669 AU 0.2579 12.97 deg 3 Juno
4 Vesta 530 300,000 5.342 hrs 3.63 yrs U 2.362 AU 0.0895 7.14 deg 4 Vesta
45 Eugenia 226 6,100 5.699 hrs 4.49 yrs FC 2.721 AU 0.0831 6.61 deg 45 Eugenia
140 Siwa 103 1,500 18.5 hrs 4.51 yrs C 2.734 AU 0.2157 3.19 deg 140 Siwa
216 Kleopatra 217 x 94 5.385 hrs 4.67 yrs M 2.793 AU 0.2535 13.14 deg 216 Kleopatra
243 Ida 58 x 23 100 4.633 hrs 4.84 yrs S 2.861 AU 0.0451 1.14 deg 243 Ida
253 Mathilde 66 x 48 x 46 103.3 417.7 hrs 4.31 yrs C 2.646 AU 0.2660 6.71 deg 253 Mathilde
433 Eros 33 x 13 x 13 6.69 5.270 hrs 1.76 yrs S 1.458 AU 0.2229 10.83 deg 433 Eros
951 Gaspra 19 x 12 x 11 10 7.042 hrs 3.29 yrs S 2.209 AU 0.1738 4.10 deg 951 Gaspra
1566 Icarus 1.4 0.001 2.273 hrs 1.12 yrs U 1.078 AU 0.8269 22.86 deg 1566 Icarus
1620 Geographos 2.0 0.004 5.222 hrs 1.39 yrs S 1.245 AU 0.3356 13.34 deg 1620 Geographos
1862 Apollo 1.6 0.002 3.063 hrs 1.81 yrs S 1.471 AU 0.5600 6.36 deg 1862 Apollo
2060 Chiron 180 4,000 5.9 hrs 50.7 yrs B 13.633 AU 0.3801 6.94 deg 2060 Chiron
2530 Shipka 5.25 yrs 3.019 AU 0.1237 10.10 deg 2530 Shipka
2703 Rodari 3.25 yrs 2.194 AU 0.0572 6.04 deg 2703 Rodari
3352 McAuliffe 2 - 5 2.57 yrs 1.879 AU 0.3686 4.77 deg 3352 McAuliffe
3840 Mimistrobell 3.38 yrs 2.249 AU 0.0831 3.92 deg 3840 Mimistrobell
4179 Toutatis 4.6 x 2.4 x 1.9 0.05 130. hrs 3.98 yrs S 2.512 AU 0.6339 0.47 deg 4179 Toutatis
4769 Castalia 1.8 x 0.8 0.0005 1.10 yrs 1.063 AU 0.4831 8.89 deg 4769 Castalia
4979 Otawara 5.5 0.2 3.19 yrs 2.168 AU 0.1449 0.91 deg 4979 Otawara
5535 AnneFrank 4.0 3.29 yrs 2.212 AU 0.0643 4.25 deg 5535 AnneFrank
9969 Braille 2.2 x 1.0 3.58 yrs 2.341 AU 0.4336 29.0 deg 9969 Braille
25143 Itokawa ~1 1.52 yrs 1.324 AU 0.2789 1.71 deg 1998 SF36
1 Ceres - The largest and first discovered asteroid, by G. Piazzi on January 1, 1801. Ceres
comprises over one-third the 2.3 x 1021 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.
45 Eugenia - Believed to have a small satellite S/1998 (45) 1 in
near circular 4.7 day orbit as reported in
IAU Circular #7129
140 Siwa - Originally scheduled for July 2008 flyby by the
Rosetta
spacecraft on its way to Comet P/Wirtanen. The mission has been rerouted.
216 Kleopatra - Imaged by Arecibo radar, shown to have
unusual "dog-bone" shape.
243 Ida - Imaged by
Galileo
on 28 August 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 being studied from orbit by the
NEAR
mission, which flew by Eros in February 1999 and went into orbit
in February 2000.
951 Gaspra - Imaged by
Galileo
on 29 Oct 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. 14 February 1996 perihelion was the subject
of the
Chiron Perihelion Campaign.
2530 Shipka - Originally scheduled for October, 2008 flyby by the
Rosetta
spacecraft on its way to Comet P/Wirtanen. The mission has been rerouted.
2703 Rodari - Originally scheduled for May, 2008 flyby by the
Rosetta
spacecraft on its way to Comet P/Wirtanen. The mission has been rerouted.
3352 McAuliffe - Amor (Mars-crossing) asteroid originally scheduled for 1999 flyby by the
New Millenium Deep Space 1
spacecraft.
3840 Mimistrobell - Originally 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. Close approach to Earth of this object
(about 1.5 million km) will occur on 29 September 2004.
4660 Nereus - Near-Earth asteroid, target of
NEAP
(Near Earth Asteroid Prospector) rendezvous.
4769 Castalia - Double-lobed near-Earth asteroid, each lobe about .75 km diameter.
Imaged by Arecibo radar.
4979 Otawara - Originally scheduled for July 2006 flyby by the
Rosetta
spacecraft on its way to Comet P/Wirtanen. The mission has been rerouted.
5535 AnneFrank - Target of November 2002 flyby by the
Stardust
spacecraft on its way to Comet P/Wild 2.
9969 Braille - Near-Earth asteroid target of 28 July 1999 flyby by the
Deep Space 1
spacecraft.
25143 Itokawa - (1998 SF36) Near-Earth asteroid target of 2005 orbit and 2007 sample return by the
Muses-C
spacecraft.
New masses calculated for 3 largest asteroids
- U.S. Naval Observatory press release, 7 January 1998
Notes on the Fact Sheets
Asteroid Home Page
Near Earth Object Fact Sheet
Directory to other Planetary Fact Sheets
Author/Curator:
Dr. David R. Williams, dwilliam@nssdc.gsfc.nasa.gov
NSSDC, Mail Code 633
NASA Goddard Space Flight Center
Greenbelt, MD 20771
+1-301-286-1258
NASA Official: Ed Grayzeck, edwin.j.grayzeck@nasa.gov
Last Updated: 01 September 2004, DRW