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
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]