5474 Gingasen, provisional designation 1988 XE1, is a Vestian asteroid and suspected binary system[4] from the inner regions of the asteroid belt, approximately 6 kilometers in diameter.

5474 Gingasen
Discovery [1]
Discovered byT. Fujii
K. Watanabe
Discovery siteKitami Obs.
Discovery date3 December 1988
MPC designation(5474) Gingasen
Named after
(railroad track, Japan)[2]
1988 XE1 · 1955 YK
1971 BO2
main-belt · Vestian[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc45.58 yr (16,649 days)
Aphelion2.5439 AU
Perihelion2.2232 AU
2.3836 AU
3.68 yr (1,344 days)
0° 16m 4.08s / day
Known satellites1 (suspected)[4][5]
(orbital period of 3.1095 h)
Physical characteristics
Dimensions5.05±0.48 km[6]
6.68 km (derived)[3]
2.91 h (superseded)[7]
3.6242±0.0003 h[4][a]
3.6272±0.0015 h[8]
3.628±0.005 h[9]
0.20 (assumed)[3]
12.70±0.2 (R)[4] · 12.79±0.10 (R)[a] · 12.886±0.002 (R)[8] · 12.90[6] · 13.1[1] · 13.14±0.35[10] · 13.28±0.112[3][11]

It was discovered on 3 December 1988, by Japanese amateur astronomers Tetsuya Fujii and Kazuro Watanabe at Kitami Observatory, Japan.[12] It is named for the "Gingasen" railroad track in Japan.[2]


Classification and orbitEdit

Gingasen is a stony S-type asteroid and member of the Vesta family. It orbits the Sun in the inner main-belt at a distance of 2.2–2.5 AU once every 3 years and 8 months (1,344 days). Its orbit has an eccentricity of 0.07 and an inclination of 6° with respect to the ecliptic.[1] First identified as 1955 YK at Alma-Ata (Tian Shan Observatory) in Kazakhstan, Gingasen's first used observation was taken in 1971, when it was identified as 1971 BO2 at Cerro El Roble Station in Chile, extending the body's observation arc by 17 years prior to its official discovery observation.[12]

Physical characteristicsEdit

Diameter and albedoEdit

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Gingasen measures 5.05 kilometers in diameter, and its surface has a high albedo of 0.480,[6] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and derives a diameter of 6.68 kilometers with an absolute magnitude of 13.28.[3]

Rotation periodEdit

Four rotational lightcurves of Gingasen were obtained by Petr Pravec, David Higgins and Pedro Sada in 2008, as well as from the Palomar Transient Factory in 2010. The lightcurves gave a well-defined rotation period of 3.624 to 3.628 hours with a brightness variation of 0.11–0.18 in magnitude (U=3/3/3-/2),[4][8][9][a] superseding a previous result by Laurent Bernasconi (U=1-).[7]

Suspected binaryEdit

During the photometric observations in 2008, the astronomers came across strong evidence that Gingasen is likely an asynchronous binary asteroid with an asteroid moon orbiting it every 3.1095 hours. However, no mutual occultation/eclipse events were observed.[4][5]


This minor planet was named after a railroad track in Hokkaido. Gingasen means "Milky Way". This 150-km public railroad connects the island's eastern cities. Each station along the line is named for a constellation.[12] The approved naming citation was published by the Minor Planet Center on 4 April 1996 (M.P.C. 26930).[13]


  1. ^ a b c Pravec (2008) web: rotation period 3.6242±0.0003 hours with a brightness amplitude of 0.18 magnitude and a quality code of 3. Summary figures for (5474) Gingasen at Collaborative Asteroid Lightcurve Link (CALL)


  1. ^ a b c d "JPL Small-Body Database Browser: 5474 Gingasen (1988 XE1)" (2016-08-27 last obs.). Jet Propulsion Laboratory. Retrieved 4 July 2017.
  2. ^ a b Schmadel, Lutz D. (2007). "(5474) Gingasen". Dictionary of Minor Planet Names – (5474) Gingasen. Springer Berlin Heidelberg. p. 468. doi:10.1007/978-3-540-29925-7_5242. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f "LCDB Data for (5474) Gingasen". Asteroid Lightcurve Database (LCDB). Retrieved 13 December 2016.
  4. ^ a b c d e f Higgins, David; Pravec, Petr; Kusnirak, Peter; Hornoch, Kamil; Pray, Donald P.; Vilagi, Jozef; et al. (October 2008). "Asteroid Lightcurve Analysis of Suspected Binary Asteroids". The Minor Planet Bulletin. 35 (4): 173–175. Bibcode:2008MPBu...35..173H. ISSN 1052-8091. Retrieved 13 December 2016.
  5. ^ a b Johnston, Robert. "(5474) Gingasen". johnstonsarchive.net. Retrieved 28 May 2015.
  6. ^ 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 13 December 2016.
  7. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (5474) Gingasen". Geneva Observatory. Retrieved 13 December 2016.
  8. ^ a b c 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 13 December 2016.
  9. ^ a b Sada, Pedro V. (October 2008). "CCD Photometry of Three Short-period Asteroids from the Universidad de Monterry Observatory". The Minor Planet Bulletin. 35 (4): 161–162. Bibcode:2008MPBu...35..161S. ISSN 1052-8091. Retrieved 13 December 2016.
  10. ^ 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 13 December 2016.
  11. ^ Pravec, Petr; Harris, Alan W.; Kusnirák, Peter; Galád, Adrián; Hornoch, Kamil (September 2012). "Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations". Icarus. 221 (1): 365–387. Bibcode:2012Icar..221..365P. doi:10.1016/j.icarus.2012.07.026. Retrieved 13 December 2016.
  12. ^ a b c "5474 Gingasen (1988 XE1)". Minor Planet Center. Retrieved 13 December 2016.
  13. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 13 December 2016.

External linksEdit