(1746) Brouwer

1746 Brouwer
001746-asteroid shape model (1746) Brouwer.png
Shape model of Brouwer from its lightcurve
Discovered byIndiana University
(Indiana Asteroid Program)
Discovery siteGoethe Link Obs.
Discovery date14 September 1963
(1746) Brouwer
Named after
Dirk Brouwer
1963 RF · 1940 WE
1947 QA
main-belt · Hilda[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc76.33 yr (27,878 days)
Aphelion4.7671 AU
Perihelion3.1284 AU
3.9478 AU
7.84 yr (2,865 days)
0° 7m 32.52s / day
Jupiter MOID0.8580 AU
Physical characteristics
Dimensions61.50±1.80 km[4]
64.25±4.9 km (IRAS:2)[3][6]
19.7255±0.0005 h[7]
19.8 h[8]
19.88±0.05 h[a]
0.0448±0.008 (IRAS:2)[3][6]
Tholen = D[1] · D[3][5]
B–V = 0.721[1]
U–B = 0.227[1]
9.78±0.30[9] · 9.95 (IRAS:2)[6] · 9.95[3][4]

1746 Brouwer (prov. designation: 1963 RF) is a Hilda asteroid from the outermost region of the asteroid belt, approximately 64 kilometers in diameter. It was discovered on 14 September 1963, by IU's Indiana Asteroid Program at Goethe Link Observatory near Brooklyn, Indiana, United States.[10] It was named after astronomer Dirk Brouwer.[2]

Classification and orbit[]

Brouwer is a member of the Hilda family, a large group that orbits in resonance with the gas giant Jupiter and are thought to originate from the Kuiper belt. Brouwer orbits the Sun at a distance of 3.1–4.8 AU once every 7 years and 10 months (2,865 days). Its orbit has an eccentricity of 0.21 and an inclination of 8° with respect to the ecliptic.[1]

It was first identified as 1940 WE at Turku Observatory in 1940, extending the body's observation arc by 23 years prior to its official discovery observation.[10]

Physical characteristics[]

In the Tholen classification, Brouwer is characterized as a dark and reddish D-type asteroid.[1]

Rotation period[]

Several rotational lightcurves of Brouwer gave a rotation period between 19.72 and 19.88 hours with a brightness variation of 0.21 and 0.35 magnitude (U=n.a/2/n.a.).[7][8][a]

Diameter and albedo[]

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Brouwer measures between 61.50 and 64.25 kilometers in diameter, and its surface has an albedo between 0.045 and 0.051.[4][5][6]

The Collaborative Asteroid Lightcurve Link agrees with IRAS, that is an albedo of 0.045 and a diameter of 64.25 kilometers with an absolute magnitude of 9.95.[3]


This minor planet was named in honor of Dutch–American astronomer Dirk Brouwer (1902–1966). Originally at Leiden University and specialized in celestial mechanics, he became director of the Yale University Observatory and was the president of IAU's commission 20, Positions & Motions of Minor Planets, Comets & Satellites, from 1948 to 1955.[2] The official naming citation was published by the Minor Planet Center on 15 July 1968 (M.P.C. 2883).[11]


  1. ^ a b Slyusarev (2012) web: rotation period 19.88±0.05 hours with a brightness amplitude of 0.21. Summary figures at Asteroid Lightcurve Database for (1746) Brouwer


  1. ^ a b c d e f g "JPL Small-Body Database Browser: 1746 Brouwer (1963 RF)" (2017-03-28 last obs.). Jet Propulsion Laboratory. Archived from the original on 5 August 2020. Retrieved 7 June 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1746) Brouwer". Dictionary of Minor Planet Names – (1746) Brouwer. Springer Berlin Heidelberg. p. 139. doi:10.1007/978-3-540-29925-7_1747. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f "LCDB Data for (1746) Brouwer". Asteroid Lightcurve Database (LCDB). Retrieved 20 December 2016.
  4. ^ 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. (online, AcuA catalog p. 153)
  5. ^ a b c d 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 20 December 2016.
  6. ^ 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.
  7. ^ a b Hanus, J.; Durech, J.; Oszkiewicz, D. A.; Behrend, R.; Carry, B.; Delbo, M.; et al. (February 2016). "New and updated convex shape models of asteroids based on optical data from a large collaboration network". Astronomy and Astrophysics. 586: 24. arXiv:1510.07422. Bibcode:2016A&A...586A.108H. doi:10.1051/0004-6361/201527441. Retrieved 20 December 2016.
  8. ^ a b Dahlgren, M.; Lahulla, J. F.; Lagerkvist, C.-I.; Lagerros, J.; Mottola, S.; Erikson, A.; et al. (June 1998). "A Study of Hilda Asteroids. V. Lightcurves of 47 Hilda Asteroids". Icarus. 133 (2): 247–285. Bibcode:1998Icar..133..247D. doi:10.1006/icar.1998.5919. Retrieved 20 December 2016.
  9. ^ 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 20 December 2016.
  10. ^ a b "1746 Brouwer (1963 RF)". Minor Planet Center. Retrieved 20 December 2016.
  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 links[]