5027 Androgeos, provisional designation 1988 BX1, is a large Jupiter trojan from the Greek camp, approximately 59 kilometers (37 miles) in diameter. It was discovered on 21 January 1988, by American astronomer Carolyn Shoemaker at the Palomar Observatory in California.[1] The dark D-type asteroid is one of the 70 largest Jupiter trojans and has a rotation period of 11.4 hours.[8] It was named from Greek mythology after the warrior Androgeos, who was killed by Aeneas.[1]

5027 Androgeos
Discovery [1]
Discovered byC. Shoemaker
Discovery sitePalomar Obs.
Discovery date21 January 1988
MPC designation(5027) Androgeos
Named after
(Greek mythology)
1988 BX1
Jupiter trojan[1][2]
Greek[3] · background[4]
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc30.34 yr (11,082 d)
Aphelion5.6486 AU
Perihelion4.9625 AU
5.3055 AU
12.22 yr (4,464 d)
0° 4m 50.52s / day
Jupiter MOID0.1142 AU
Physical characteristics
Mean diameter
57.86±4.3 km[5]
59.79±0.64 km[6]
11.376±0.004 h[7][a]
D (Pan-STARRS)[8][9]
D (SDSS-MOC)[10]
V–I = 0.910±0.033[8]


Orbit and classificationEdit

Androgeos is a dark Jovian asteroid orbiting in the leading Greek camp at Jupiter's L4 Lagrangian point, 60° ahead of the Gas Giant's orbit in a 1:1 resonance (see Trojans in astronomy). It is also a non-family asteroid in the Jovian background population.[4]

It orbits the Sun at a distance of 5.0–5.6 AU once every 12 years and 3 months (4,464 days; semi-major axis of 5.31 AU). Its orbit has an eccentricity of 0.06 and an inclination of 31° with respect to the ecliptic.[2] The body's observation arc begins with its official discovery observation at Palomar.[1]

Physical characteristicsEdit

Androgeos has been characterized as a dark D-type asteroid by Pan-STARRS' survey and in the SDSS-based taxonomy.[8][9][10]

Rotation periodEdit

In May 2016, a rotational lightcurve of Androgeos was obtained from photometric observations by Robert Stephens at the Center for Solar System Studies in California. Lightcurve analysis gave a rotation period of 11.376±0.004 hours with a brightness amplitude of 0.37 magnitude (U=3).[8][7][a]

This result supersedes similar period determinations with an amplitude of 0.31 and 0.64 by Stefano Mottola (1992) Stephens (2015), respectively (U=3).[8][11][12][a]

Diameter and albedoEdit

According to the survey carried out by the Infrared Astronomical Satellite IRAS and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Androgeos measures 57.86 and 59.79 kilometers in diameter and its surface has an albedo of 0.091 and 0.071, respectively.[5][6] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0767 and a diameter of 57.68 kilometers based on an absolute magnitude of 9.6.[8]


This minor planet was named by the discoverer from Greek mythology after Androgeos, the Greek warrior who was killed by Aeneas in the burning city of Troy. Aeneas and his Trojan men then took the armor of Androgeos and his killed troops to disguised themselves and escape to safety. The official naming citation was published by the Minor Planet Center on 4 June 1993 (M.P.C. 22248).[13]


  1. ^ a b c Lightcurve plots of (5027) Androgeos from Jun 2015 and May 2016 by Robert Stephens at the Center for Solar System Studies (U81). Quality code is 3/3 (lightcurve rating at CS3). Summary figures at the LCDB and CS3 website.


  1. ^ a b c d e f "5027 Androgeos (1988 BX1)". Minor Planet Center. Retrieved 15 June 2018.
  2. ^ a b c d "JPL Small-Body Database Browser: 5027 Androgeos (1988 BX1)" (2018-05-25 last obs.). Jet Propulsion Laboratory. Retrieved 15 June 2018.
  3. ^ "List of Jupiter Trojans". Minor Planet Center. 1 June 2018. Retrieved 15 June 2018.
  4. ^ a b "Asteroid (5027) Androgeos – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 15 June 2018.
  5. ^ 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 15 June 2018.
  6. ^ a b c d Grav, T.; Mainzer, A. K.; Bauer, J. M.; Masiero, J. R.; Nugent, C. R. (November 2012). "WISE/NEOWISE Observations of the Jovian Trojan Population: Taxonomy". The Astrophysical Journal. 759 (1): 10. arXiv:1209.1549. Bibcode:2012ApJ...759...49G. doi:10.1088/0004-637X/759/1/49. Retrieved 15 June 2018. (online catalog)
  7. ^ a b Stephens, Robert D.; Coley, Daniel R.; Warner, Brian D.; French, Linda, M. (October 2016). "Lightcurves of Jovian Trojan Asteroids from the Center for Solar System Studies: L4 Greek Camp and Spies". The Minor Planet Bulletin. 43 (4): 323–331. Bibcode:2016MPBu...43..323S. ISSN 1052-8091. Retrieved 15 June 2018.
  8. ^ a b c d e f g h "LCDB Data for (5027) Androgeos". Asteroid Lightcurve Database (LCDB). Retrieved 15 June 2018.
  9. ^ 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" (PDF). Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 15 June 2018.
  10. ^ a b Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids". Astronomy and Astrophysics. 510: 12. Bibcode:2010A&A...510A..43C. doi:10.1051/0004-6361/200913322. Retrieved 15 June 2018.
  11. ^ Mottola, Stefano; Di Martino, Mario; Erikson, Anders; Gonano-Beurer, Maria; Carbognani, Albino; Carsenty, Uri; et al. (May 2011). "Rotational Properties of Jupiter Trojans. I. Light Curves of 80 Objects". The Astronomical Journal. 141 (5): 32. Bibcode:2011AJ....141..170M. doi:10.1088/0004-6256/141/5/170. Retrieved 15 June 2018.
  12. ^ Stephens, Robert D.; Coley, Daniel, R.; French, Linda M. (January 2016). "Large L5 Jovian Trojan Asteroid Lightcurves from the Center for Solar System Studies". The Minor Planet Bulletin. 43 (1): 15–22. Bibcode:2016MPBu...43...15S. ISSN 1052-8091. Retrieved 15 June 2018.
  13. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 15 June 2018.

External linksEdit