1578 Kirkwood

1578 Kirkwood, provisional designation 1951 AT, is a Hilda asteroid from the outermost regions of the asteroid belt, approximately 52 kilometers in diameter. It was discovered on 10 January 1951, by astronomers of the Indiana Asteroid Program at Goethe Link Observatory in Indiana, United States.[3] The asteroid was named after American astronomer Daniel Kirkwood.[2]

1578 Kirkwood
001578-asteroid shape model (1578) Kirkwood.png
Shape model of Kirkwood from its lightcurve
Discovery [1]
Discovered byIndiana University
(Indiana Asteroid Program)
Discovery siteGoethe Link Obs.
Discovery date10 January 1951
(1578) Kirkwood
Named after
Daniel Kirkwood[2]
(American astronomer)
1951 AT · 1944 DF
1949 TF · 1952 FK
main-belt · (outer)[1]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc73.37 yr (26,797 days)
Aphelion4.8617 AU
Perihelion2.9855 AU
3.9236 AU
7.77 yr (2,839 days)
0° 7m 36.48s / day
Jupiter MOID0.4366 AU
Physical characteristics
Dimensions47.077±0.315 km[6]
51.88±1.8 km[4][7]
57.14±1.27 km[8]
12.518±0.002 h[9]
17.9±0.1 h[a]
Tholen = D[1] · D[4][10]
B–V = 0.788[1]
U–B = 0.276[1]
10.26[1][4][7][8] · 10.41±0.50[10]

Orbit and classificationEdit

Kirkwood belongs to the orbital Hilda group, which is located outermost part of the main belt.[4] Asteroids in this dynamical group have semi-major axis between 3.7 and 4.2 AU and stay in a 3:2 resonance with the gas giant Jupiter. Kirkwood, however, is a background asteroid and not a member of the (collisional) Hilda family (101).[5]

It orbits the Sun at a distance of 3.0–4.9 AU once every 7 years and 9 months (2,839 days). Its orbit has an eccentricity of 0.24 and an inclination of 1° with respect to the ecliptic.[1]

The asteroid was first observed as 1944 DF at Turku Observatory in February 1944. The body's observation arc begins with its observation as 1949 TF at Heidelberg Observatory in October 1949, fifteen months prior to its official discovery observation at Goethe Link.[3]

Physical characteristicsEdit

In the Tholen classification, Kirkwood is a dark D-type asteroid.[1] It is also characterized as a D-type by PanSTARRS photometric survey.[10]

Rotation periodEdit

In October 2012, a rotational lightcurve of Kirkwood was obtained from photometric observations at the Etscorn Campus Observatory (719) in New Mexico, United States. Lightcurve analysis gave a rotation period of 12.518 hours with a brightness variation of 0.05 magnitude (U=2). Another lightcurve gave a period of 17.9 hours and an amplitude of 0.22 magnitude (U=2).[a]

Diameter and albedoEdit

According to the surveys carried out by the Japanese Akari satellite, the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer and the Infrared Astronomical Satellite IRAS, Kirkwood measures between 47.077 and 57.14 kilometers in diameter and its surface has an albedo between 0.044 and 0.063.[6][7][8]

The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0517 and a diameter of 51.88 kilometers based on an absolute magnitude of 10.26.[4]


This minor planet was named in memory of American astronomer Daniel Kirkwood (1814–1895), long-time professor of mathematics at Indiana University. He discovered the Kirkwood gaps, which are gaps in the distribution of the mean distances of the minor planets in the asteroid belt. Kirkwood was the Indiana Asteroid Program's first numbered discovery.[2][b] The official naming citation was published by the Minor Planet Center in March 1952 (M.P.C. 738).[11] The lunar crater Kirkwood was also named in the astronomer's honor.[2]


  1. ^ a b Slyusarev (2012) web; for (1578) Kirkwood: rotation period of 17.9 hours with a brightness amplitude of 0.22 mag. Summary figures given at the LCDB
  2. ^ Although the asteroid 1575 Winifred, also discovered by the Indiana Asteroid Program, has both a lower number and an earlier discovery date (20 April 1950) than 1578 Kirkwood


  1. ^ a b c d e f g h i "JPL Small-Body Database Browser: 1578 Kirkwood (1951 AT)" (2017-07-04 last obs.). Jet Propulsion Laboratory. Retrieved 21 September 2017.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(1578) Kirkwood". Dictionary of Minor Planet Names – (1578) Kirkwood. Springer Berlin Heidelberg. p. 125. doi:10.1007/978-3-540-29925-7_1579. ISBN 978-3-540-00238-3.
  3. ^ a b c "1578 Kirkwood (1951 AT)". Minor Planet Center. Retrieved 21 September 2017.
  4. ^ a b c d e f g "LCDB Data for (1578) Kirkwood". Asteroid Lightcurve Database (LCDB). Retrieved 21 September 2017.
  5. ^ a b "Asteroid 1578 Kirkwood – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 29 October 2019.
  6. ^ a b c Grav, T.; Mainzer, A. K.; Bauer, J.; Masiero, J.; Spahr, T.; McMillan, R. S.; et al. (January 2012). "WISE/NEOWISE Observations of the Hilda Population: Preliminary Results". The Astrophysical Journal. 744 (2): 15. arXiv:1110.0283. Bibcode:2012ApJ...744..197G. doi:10.1088/0004-637X/744/2/197. Retrieved 21 September 2017.
  7. ^ a b c d Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System – IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 17 October 2019.
  8. ^ a b c d Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. Retrieved 17 October 2019. (online, AcuA catalog p. 153)
  9. ^ Klinglesmith, Daniel A., III; Hanowell, Jesse; Risley, Ethan; Turk, Janek; Vargas, Angelica; Warren, Curtis Alan (April 2013). "Asteroid Synodic Periods from Etscorn Campus Observatory". The Minor Planet Bulletin. 40 (2): 65–67. Bibcode:2013MPBu...40...65K. ISSN 1052-8091. Retrieved 21 September 2017.
  10. ^ a b c 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 21 September 2017.
  11. ^ Schmadel, Lutz D. "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.

External linksEdit