2153 Akiyama, provisional designation 1978 XD, is a carbonaceous Themistian asteroid from the outer region of the asteroid belt, approximately 17 kilometers in diameter.
The asteroid was discovered by staff members at the
Agassiz Station of the Harvard College Observatory on 1 December 1978, and named Japanese astronomer Kaoru Akiyama.
Orbit and classification
Akiyama is a member of the Themis family, a dynamical family of outer-belt asteroids with nearly coplanar ecliptical orbits. It orbits the Sun at a distance of 2.6–3.6 AU once every 5 years and 6 months (2,017 days). Its orbit has an eccentricity of 0.15 and an inclination of 1 ° with respect to the ecliptic. A first  precovery was taken at Palomar Observatory in 1954, extending the asteroid's observation arc by 24 years prior to its discovery.
Akiyama has been characterized as a dark C-type asteroid.
Diameter and albedo
According to the space-based surveys carried out by the Infrared Astronomical Satellite
IRAS and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Akiyama measures 16.8 and 21.2 kilometers in diameter, respectively, with a corresponding albedo of 0.11 and 0.07.  The  Collaborative Asteroid Lightcurve Link assumes an intermediary albedo of 0.08 and calculates a diameter of 15.4 kilometers with an absolute magnitude of 12.42.
lightcurves of Akiyama were obtained from photometric observations made at the U.S. Palomar Transient Factory in October 2010 and January 2012. They showed a rotation period of and 12.5325 ±0.0053 hours with a brightness variation of 0.26 and 0.27 in 12.5132 ±0.0053 magnitude, respectively ( ). U=2/2
minor planet was named in memory of Japanese astronomer Kaoru Akiyama (1901–1970), professor at Hosei University, Tokyo, and widely known for his studies on minor planets. In collaboration with astronomer Kiyotsugu Hirayama, after whom the asteroid 1999 Hirayama is named, he made the first detailed orbital analysis of the asteroid 153 Hilda, which has a 2:3 orbital resonance with Jupiter. The official naming citation was published by the  Minor Planet Center on 1 November 1979 ( ). M.P.C. 5014
^ a b c d e f g
"JPL Small-Body Database Browser: 2153 Akiyama (1978 XD)" (2017-03-29 last obs.). Jet Propulsion Laboratory . Retrieved . 11 June 2017
^ a b
Schmadel, Lutz D. (2007). "(2153) Akiyama". Dictionary of Minor Planet Names – (2153) Akiyama. Springer Berlin Heidelberg. p. 175. doi: 10.1007/978-3-540-29925-7_2154. ISBN . 978-3-540-00238-3
^ a b c d e f g
"LCDB Data for (2153) Akiyama". Asteroid Lightcurve Database (LCDB) . Retrieved . 4 May 2016
^ a b c d
Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv: . 1209.5794 Bibcode: 2012ApJ...759L...8M. doi: 10.1088/2041-8205/759/1/L8 . Retrieved . 4 May 2016
^ 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 . 4 May 2016
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 . 4 May 2016
^ a b
"2153 Akiyama (1978 XD)". Minor Planet Center . Retrieved . 4 May 2016
"MPC/MPO/MPS Archive" (PDF). Minor Planet Center (PDF). p. 78. ISSN 0736-6884 . Retrieved . 4 May 2016