168 Sibylla

From Wikipedia the free encyclopedia

168 Sibylla
Orbital diagram
Discovery[1]
Discovered byJ. C. Watson
Discovery siteAnn Arbor
Discovery date28 September 1876
Designations
(168) Sibylla
Pronunciation/sɪˈbɪlə/[2]
Named after
Sibyls
A876 SA; 1911 HF;
1949 MO
main-belt
AdjectivesSibyllian /sɪˈbɪliən/
Orbital characteristics[3][4]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc136.01 yr (49676 d)
Aphelion3.6215 AU (541.77 Gm)
Perihelion3.1417 AU (469.99 Gm)
3.3816 AU (505.88 Gm)
Eccentricity0.070943
6.22 yr (2271.4 d)
16.19 km/s
171.517°
0° 9m 30.564s / day
Inclination4.6617°
205.959°
173.920°
Physical characteristics
Dimensions148.39±4.0 km[3]
149.06 ± 4.29 km[5]
Mass(3.92 ± 1.80) × 1018 kg[5]
Mean density
2.26 ± 1.05 g/cm3[5]
47.009 h (1.9587 d)
23.82 hours[6]
0.0535±0.003
C
7.94

168 Sibylla is a large main-belt asteroid, discovered by Canadian-American astronomer J. C. Watson on September 28, 1876. It was most likely named for the Sibyls, referring to the Ancient Greek female oracles.[7] 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.[6] The shape of this slowly rotating object appears to resemble an oblate spheroid.[8]

References

[edit]
  1. ^ "Discovery Circumstances: Numbered Minor Planets (1)-(5000)". Retrieved 14 August 2012.
  2. ^ "Sibylla". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  3. ^ a b Yeomans, Donald K., "168 Sibylla", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 12 May 2016.
  4. ^ "The Asteroid Orbital Elements Database". astorb. Lowell Observatory. Retrieved 14 August 2012.
  5. ^ a b c Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, 73 (1): 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009, S2CID 119226456. See Table 1.
  6. ^ 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.
  7. ^ Schmadel, Lutz (2003), Dictionary of Minor Planet Names, Physics and astronomy online library, vol. 1, Springer Science & Business Media, p. 30, ISBN 9783540002383.
  8. ^ Wang, Xiaobin; et al. (January 2016), "Studies for slowly rotating asteroids (168) Sibylla and (346) Hermentaria", Asteroids: New Observations, New Models, Proceedings of the International Astronomical Union, IAU Symposium, vol. 318, pp. 185–192, Bibcode:2016IAUS..318..185W, doi:10.1017/S1743921315008777.
[edit]