216 Kleopatra

216 Kleopatra

Discovery
Discovered by	Johann Palisa
Discovery date	April 10, 1880
Designations
Alternative names	A905 OA, A910 RA
Minor planet category	Main belt
Orbital characteristics
Epoch 30 January, 2005 (JD 2453400.5)
Aphelion	523.049 Gm (3.496 AU)
Perihelion	312.544 Gm (2.089 AU)
Semi-major axis	417.796 Gm (2.793 AU)
Eccentricity	0.252
Orbital period	1704.704 d (4.67 a)
Average orbital speed	17.82 km/s
Mean anomaly	55.259°
Inclination	13.136°
Longitude of ascending node	215.672°
Argument of perihelion	179.099°
Physical characteristics
Dimensions	217 × 94 × 81 km
Mass	unknown
Mean density	3.5+
Rotation period	5.385 h

216 Kleopatra is a Main belt asteroid found by Johann Palisa on April 10, 1880 in Pola. It is named after Cleopatra, the Queen of Egypt.

Dog bone shaped asteroid Kleopatra

Kleopatra is an unusual object. Its odd shape was revealed by adaptive optics on the ESO 3.6m telescope at La Silla. By bouncing radar signals off the asteroid, a team of astronomers at the Arecibo radio telescope in Puerto Rico were able to develop a more detailed computer model of its shape, which confirmed the dog-bone like shape. A favored explanation is that Kleopatra is a contact binary: two similarly-sized asteroids that have hit and stuck together instead of breaking apart.

Kleopatra is a fairly big asteroid, measuring 217 × 94 × 81 km. It is believed to be a loosely packed metallic object, based on its radar albedo.

Other websites

• Bilobated shape of 216 Kleopatra
• Astronomers Catch Images of Giant Metal Dog Bone Asteroid – NASA article
• An Asteroid for the Dogs

References

• The Asteroid Orbital Elements Database
• Minor Planet Discovery Circumstances
• Asteroid Lightcurve Data File