12564 Ikeller

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
12564 Ikeller
Discovery [1]
Discovered by W. Bickel
Discovery site Bergisch Gladbach Obs.
Discovery date 22 September 1998
MPC designation (12564) Ikeller
Named after
Ingeborg Bickel–Keller
(discoverer's wife)[2]
1998 SO49 · 1988 RA7
1991 EG5 · 1993 SK13
main-belt · Koronis[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 27.90 yr (10,190 days)
Aphelion 2.9423 AU
Perihelion 2.7273 AU
2.8348 AU
Eccentricity 0.0379
4.77 yr (1,743 days)
0° 12m 23.4s / day
Inclination 1.6200°
Physical characteristics
Dimensions 5.17 km (calculated)[3]
5.369±0.259 km[4][5]
7.0321±0.0196 h (R)[6]
7.0423±0.0196 h (S)[6]
0.24 (assumed)[3]
13.6[1][3][4] · 13.644±0.003 (R)[6] · 14.16±0.23[7] · 14.282±0.007 (S)[6]

12564 Ikeller, provisional designation 1998 SO49, is a stony Koronian asteroid from the outer region of the asteroid belt, approximately 5 kilometers in diameter.

The asteroid was discovered by German amateur astronomer Wolf Bickel at his private Bergisch Gladbach Observatory on 22 September 1998. It was named after the discoverer's wife, Ingeborg Bickel–Keller.[2]

Orbit and classification[edit]

Ikeller is a member of the Koronis family, a group of stony asteroids in the outer main-belt named after 158 Koronis. It orbits the Sun at a distance of 2.7–2.9 AU once every 4 years and 9 months (1,743 days). Its orbit has an eccentricity of 0.04 and an inclination of 2° with respect to the ecliptic.[1]

The body's observation arc begins 10 years prior to its official discovery observation, with its identification as 1988 RA7 at ESO's La Silla Observatory in September 1988.[2]

Physical characteristics[edit]

According to the survey carried out by the NEOWISE mission of NASA's space-based Wide-field Infrared Survey Explorer, Ikeller measures 5.4 kilometers in diameter and its surface has an albedo of 0.22,[4] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for Koronian asteroids of 0.24 and thus calculates a smaller diameter of 5.2 kilometers, as the higher the albedo (reflectivity), the smaller a body's diameter at a certain absolute magnitude (brightness).[3]


In August 2012, a photometric lightcurve of Ikeller was obtained from photometric observations by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of 7.0423 hours with a brightness variation of 0.44 magnitude (U=2).[6]


This minor planet was named by the discoverer after his wife, Ingeborg Bickel–Keller (born 1941).[2] The approved naming citation was published by the Minor Planet Center on 16 January 2014 (M.P.C. 86713).[8]


  1. ^ a b c d "JPL Small-Body Database Browser: 12564 Ikeller (1998 SO49)" (2016-08-03 last obs.). Jet Propulsion Laboratory. Retrieved 24 June 2017.
  2. ^ a b c d "12564 Ikeller (1998 SO49)". Minor Planet Center. Retrieved 5 April 2016.
  3. ^ a b c d e f "LCDB Data for (12564) Ikeller". Asteroid Lightcurve Database (LCDB). Retrieved 17 May 2016.
  4. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 17 May 2016.
  5. ^ a b Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 4 December 2016.
  6. ^ a b c d e Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). "Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry". The Astronomical Journal. 150 (3): 35. arXiv:1504.04041. Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75. Retrieved 17 May 2016.
  7. ^ Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 17 May 2016.
  8. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 17 May 2016.

External links[edit]