2895 Memnon

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2895 Memnon
Discovery [1]
Discovered byN. G. Thomas
Discovery siteAnderson Mesa Stn.
Discovery date10 January 1981
Designations
(2895) Memnon
Pronunciation/ˈmɛmnɒn/ MEM-non
Named after
Memnon
(Greek mythology)[2]
1981 AE1 · 1981 CL
Jupiter trojan [3]
(Trojan camp)[4]
Orbital characteristics [1]
Epoch 16 February 2017 (JD 2457800.5)
Uncertainty parameter 0
Observation arc38.91 yr (14,213 days)
Aphelion5.5010 AU
Perihelion4.9777 AU
5.2393 AU
Eccentricity0.0499
11.99 yr (4,380 days)
87.441°
0° 4m 55.92s / day
Inclination27.213°
133.98°
277.13°
Jupiter MOID0.1255 AU
TJupiter2.7760
Physical characteristics
Dimensions55.67 km (calculated)[5]
56.706±0.200 km[6][7]
7 h[8]
7.5 h[9]
7.502±0.010 h[10]
7.509±0.006 h[11]
7.55±0.01 h[12]
0.057 (assumed)[5]
0.060±0.016[6][7]
C [5]
9.9[7][6] · 10.0[1][5] · 10.09±0.22[13]

2895 Memnon, provisional designation 1981 AE1, is a carbonaceous Jupiter trojan from the Trojan camp, approximately 56 kilometers in diameter. It was discovered on 10 January 1981, by American astronomer Norman G. Thomas at Lowell's Anderson Mesa Station near Flagstaff, Arizona, United States.[3]

Memnon is a C-type asteroid and resides in the Trojan camp of Jupiter's L5 Lagrangian point, which lies 60° behind the gas giant's orbit (see Trojans in astronomy).[4] It orbits the Sun at a distance of 5.0–5.5 AU once every 11 years and 12 months (4,380 days). Its orbit has an eccentricity of 0.05 and an inclination of 27° with respect to the ecliptic.[1] Due to a precovery taken at the Australian Siding Spring Observatory in 1977, Memnon's observation arc begins 4 years prior to its official discovery observation.[3]

The first rotational light-curve of Memnon was obtained by Richard P. Binzel in the early 1980s. It gave a rotation period of 7.5 hours with a brightness variation of 0.24 magnitude (U=2).[9] In November 1990, Italian ESO astronomer Stefano Mottola obtained a period of 7.502 hours with an amplitude of 0.22 magnitude (U=3-).[10] In January 2015 and 2016, photometric observations by amateur astronomer Robert D. Stephens gave a period of 7.55 and 7.509 hours, with a brightness variation of 0.33 and 0.08, respectively (U=2/n.a.).[11][12]

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Memnon measures 56.70 kilometers in diameter, and its surface has an albedo of 0.060,[6][7] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 55.67 kilometers, using an absolute magnitude of 10.0.[5]

This Trojan asteroid was named for Memnon from Greek mythology. He was the king of Ethiopia and nephew of king Priam of Troy. He supported the Trojan side in the Trojan War with 10,000 men and was killed in combat by Achilles.[2] Naming citation was published on 20 December 1983 (M.P.C. 8405).[14]

References

  1. ^ a b c d "JPL Small-Body Database Browser: 2895 Memnon (1981 AE1)" (2016-11-05 last obs.). Jet Propulsion Laboratory. Retrieved 27 December 2016.
  2. ^ a b Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (2895) Memnon. Springer Berlin Heidelberg. p. 238. ISBN 978-3-540-00238-3. Retrieved 27 December 2016.
  3. ^ a b c "2895 Memnon (1981 AE1)". Minor Planet Center. Retrieved 27 December 2016.
  4. ^ a b "List of Jupiter Trojans". Minor Planet Center. 20 June 2016. Retrieved 27 December 2016.
  5. ^ a b c d e "LCDB Data for (2895) Memnon". Asteroid Lightcurve Database (LCDB). Retrieved 27 December 2016.
  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 27 December 2016.
  7. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results" (PDF). The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 27 December 2016.
  8. ^ Behrend, Raoul. "Asteroids and comets rotation curves – (2895) Memnon". Geneva Observatory. Retrieved 27 December 2016.
  9. ^ a b Binzel, Richard P.; Sauter, Linda M. (February 1992). "Trojan, Hilda, and Cybele asteroids - New lightcurve observations and analysis". Icarus: 222–238. Bibcode:1992Icar...95..222B. doi:10.1016/0019-1035(92)90039-A. ISSN 0019-1035. Retrieved 27 December 2016.
  10. ^ a b 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 27 December 2016.
  11. ^ a b Stephens, Robert D.; Coley, Daniel R.; French, Linda M. (July 2016). "A Report from the L5 Trojan Camp - Lightcurves of Jovian Trojan Asteroids from the Center for Solar System Studies". The Minor Planet Bulletin. 43 (3): 265–270. Bibcode:2016MPBu...43..265S. ISSN 1052-8091. Retrieved 27 December 2016.
  12. ^ a b Stephens, Robert D.; Coley, Daniel R.; French, Linda M. (July 2015). "Dispatches from the Trojan Camp - Jovian Trojan L5 Asteroids Observed from CS3: 2014 October - 2015 January". The Minor Planet Bulletin. 42 (3): 216–224. Bibcode:2015MPBu...42R.216S. ISSN 1052-8091. Retrieved 27 December 2016.
  13. ^ 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 27 December 2016.
  14. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 27 December 2016.

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=2895_Memnon&oldid=780291941"