168 Sibylla

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168 Sibylla
Discovery[1]
Discovered by J. C. Watson
Discovery site Ann Arbor
Discovery date September 28, 1876 (1876-09-28)
Orbital characteristics[2][3]
Aphelion 3.601 AU
Perihelion 3.154 AU
3.377 AU
Eccentricity 0.066
6.21 years
16.19 km/s
261.860°
Inclination 4.63°
206.469°
168.166
Physical characteristics
Dimensions 149.06 ± 4.29[4] km
Mass (3.92 ± 1.80) × 1018[4] kg
Mean density
2.26 ± 1.05[4] g/cm3
23.82[5] hours
Albedo 0.054
Spectral type
C
7.94

168 Sibylla is a large main-belt asteroid, discovered by Canadian-American astronomer J. C. Watson on September 28, 1876. Based upon its spectrum this object is classified as a C-type asteroid, which indicates it is very dark and composed of primitive carbonaceous materials. 168 Sibylla is a Cybele asteroid, orbiting beyond most of the main-belt asteroids.

Photometric observations of this asteroid made at the Torino Observatory in Italy during 1990–1991 were used to determine a synodic rotation period of 23.82 ± 0.004 hours.[5]

References[edit]

  1. ^ "Discovery Circumstances: Numbered Minor Planets (1)-(5000)". Retrieved August 14, 2012. 
  2. ^ Yeomans, Donald K., "168 Sibylla", JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), retrieved 2013-03-25. 
  3. ^ "The Asteroid Orbital Elements Database". Retrieved August 14, 2012. 
  4. ^ a b c Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73: 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009.  See Table 1.
  5. ^ a b di Martino, M. et al. (February 1994), "Lightcurves and rotational periods of nine main belt asteroids", Icarus 107 (2): 269–275, Bibcode:1994Icar..107..269D, doi:10.1006/icar.1994.1022.