129 Antigone

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129 Antigone
129Antigone (Lightcurve Inversion).png
A three-dimensional model of 129 Antigone based on its light curve.
Discovery
Discovered by Christian Heinrich Friedrich Peters
Discovery date February 5, 1873
Designations
Named after
Antigone
Minor planet category Main belt
Orbital characteristics[1]
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 520.360 Gm (3.478 AU)
Perihelion 337.731 Gm (2.258 AU)
429.045 Gm (2.868 AU)
Eccentricity 0.213
1774.045 d (4.86 a)
17.39 km/s
110.610°
Inclination 12.218°
136.437°
108.207°
Physical characteristics
Dimensions 119.44 ± 3.91[2] km
Mass (2.65 ± 0.89) × 1018[2] kg
Mean density
2.96 ± 1.04[2] g/cm3
0.0349 m/s²
0.0661 km/s
4.9572[3] h
Temperature ~164 K
Spectral type
M
9.71 (brightest?)
7.07

129 Antigone is a large main-belt asteroid. Radar observations indicate that it is composed of almost pure nickel-iron. It and other similar asteroids probably originate from the core of a shattered Vesta-like planetesimal which had a differentiated interior. It was discovered by German-American astronomer C. H. F. Peters on February 5, 1873, and named after Antigone, the Theban princess in Greek mythology.

In 1979 a possible satellite of Antigone was suggested based on lightcurve data.[4] A model constructed from these shows Antigone itself to be quite regularly shaped. In 1990, the asteroid was observed from the Collurania-Teramo Observatory, allowing a composite light curve to be produced that showed a rotation period of 4.9572 ± 0.0001 hours and a brightness variation of 0.34 ± 0.01 in magnitude. The ratio of the lengths of the major to minor axes for this asteroid were found to be 1.45 ±0.02.[3]

10µ radiometric data collected from Kitt Peak in 1975 gave a diameter estimate of 114 km.[5] Since 1985, a total of three stellar occultations by Antigone have been observed. A favorable occultation of a star on April 11, 1985 was observed from sites near Pueblo, Colorado, allowing a diameter estimate of 113.0 ± 4.2 km to be calculated.[6]

References[edit]

  1. ^ Yeomans, Donald K., 129 Antigone, JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), retrieved 2013-03-29. 
  2. ^ 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.
  3. ^ a b Dotto, E. et al. (June 1992), M-type asteroids - Rotational properties of 16 objects, Astronomy and Astrophysics Supplement Series 95 (2): 195–211, Bibcode:1992A&AS...95..195D. 
  4. ^ Johnston, Wm. Robert (February 17, 2013), Other Reports of Asteroid/TNO Companions, Juhnson's Archive, retrieved 2013-03-29. 
  5. ^ Morrison, D.; Chapman, C. R. (March 1976), Radiometric diameters for an additional 22 asteroids, Astrophysical Journal 204: 934–939, Bibcode:2008mgm..conf.2594S, doi:10.1142/9789812834300_0469. 
  6. ^ Wasserman, L. H. et al. (June 1986), The Occultation of AG + 20° 1138 by 129 Antigone on 11 April 1985, Bulletin of the American Astronomical Society 18: 797, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. 

External links[edit]