209 Dido

209 Dido

Discovery
Discovered by	C. H. F. Peters
Discovery date	October 22, 1879
Designations
Named after	Dido
Alternative names	A909 AB, A909 GB, A912 RB
Minor planet category	Main belt
Adjectives	Didonian
Orbital characteristics
Epoch 30 January 2005 (JD 2453400.5)
Aphelion	501.211 Gm (3.35 AU)
Perihelion	440.569 Gm (2.945 AU)
Semi-major axis	470.89 Gm (3.148 AU)
Eccentricity	0.064
Orbital period	2039.771 d (5.58 a)
Average orbital speed	16.79 km/s
Mean anomaly	287.741°
Inclination	7.181°
Longitude of ascending node	0.844°
Argument of perihelion	250.781°
Physical characteristics
Dimensions	140.35 ± 10.12[1] km
Mass	(4.59 ± 7.42) × 10^18 kg[1]
Rotation period	5.7366[2] h
Albedo	0.035
Spectral type	C
Absolute magnitude (H)	8.24

209 Dido is a very large main-belt asteroid. It is classified as a C-type asteroid and is probably composed of carbonaceous materials. Like many asteroids of its type, it has an extremely low albedo.

It was discovered by C. H. F. Peters on October 22, 1879 in Clinton, New York and was named after the mythical Carthaginian queen Dido.

Photometric observations at the Palmer Divide Observatory during 2005 showed a rotation period of 5.7366 ± 0.0005 hours with a brightness variation of 0.17 ± 0.02 in magnitude.^[2]

References

1. Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73, pp. 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
2. Warner, Brian D. (December 2005), "Asteroid lightcurve analysis at the Palmer Divide Observatory - spring 2005", The Minor Planet Bulletin 32 (4): 90–92, Bibcode:2005MPBu...32...90W.

External links

• The Asteroid Orbital Elements Database
• Minor Planet Discovery Circumstances
• Asteroid Lightcurve Data File
• 209 Dido at the JPL Small-Body Database

• Discovery · Orbit diagram · Orbital elements · Physical parameters