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4791 Iphidamas - Wikipedia

  • ️Tue May 22 2018

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4791 Iphidamas
Discovery [1]
Discovered byC. Shoemaker
Discovery sitePalomar Obs.
Discovery date14 August 1988
Designations
(4791) Iphidamas
Pronunciation[2]

Named after

Iphidamas [1]
(Greek mythology)
1988 PB1
Jupiter trojan [1][3]
Trojan [4] · background [5]
AdjectivesIphidamantian
Orbital characteristics [3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc29.77 yr (10,874 d)
Aphelion5.3969 AU
Perihelion4.9230 AU
5.1600 AU
Eccentricity0.0459
11.72 yr (4,281 d)
91.938°
0° 5m 2.76s / day
Inclination25.970°
261.46°
165.77°
Jupiter MOID0.1002 AU
TJupiter2.7970
Physical characteristics
49.53±0.66 km[6]
57.85±4.0 km[7]
59.96±1.79 km[8]
9.696±0.006 h[9][a]
0.055±0.004[8]
0.0579±0.009[7]
0.079±0.005[6]
C (assumed)[10]
B–V = 0.670±0.060[11]
V–R = 0.610±0.040[11]
V–I = 1.030±0.049[10]
9.90[6][7][8]
10.1[1][3][10]

4791 Iphidamas is a Jupiter trojan from the Trojan camp, approximately 58 kilometers (36 miles) in diameter. It was discovered on 14 August 1988, by American astronomer Carolyn Shoemaker at the Palomar Observatory in California.[1] The dark Jovian asteroid belongs the 100 largest Jupiter trojans and has a rotation period of 9.7 hours.[10] It was named after the Trojan warrior Iphidamas, from Greek mythology.[1]

Orbit and classification

[edit]

Iphidamas is a dark Jupiter trojan in a 1:1 orbital resonance with Jupiter. It is located in the trailering Trojan camp at the Gas Giant's L5 Lagrangian point, 60° behind its orbit (see Trojans in astronomy).[4] It is also a non-family asteroid of the Jovian background population.[5]

It orbits the Sun at a distance of 4.9–5.4 AU once every 11 years and 9 months (4,281 days; semi-major axis of 5.16 AU). Its orbit has an eccentricity of 0.05 and an inclination of 26° with respect to the ecliptic.[3] The body's observation arc begins with its official discovery observation at Palomar in August 1988.[1]

Physical characteristics

[edit]

Iphidamas is an assumed, carbonaceous C-type asteroid. It has a high V–I color index of 1.03 (see table below).[10]

In 2014 and 2015, two rotational lightcurves of Iphidamas were obtained from photometric observations by Robert Stephens at the Center for Solar System Studies in Landers, California. Analysis of the best-rated lightcurve from December 2015 showed a rotation period of 9.696±0.006 hours with a brightness amplitude of 0.31 magnitude (U=3),[9][12][a] superseding a previous period determination by Stefano Mottola at the La Silla Observatory from February 1992, which gave a similar period of 9.57 hours (U=2+).[10][13]

Diameter and albedo

[edit]

According to the surveys carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the Infrared Astronomical Satellite IRAS, and the Japanese Akari satellite, Iphidamas measures between 49.528 and 59.96 kilometers in diameter and its surface has an albedo between 0.055 and 0.079.[6][7][8] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0483 and a diameter of 57.74 kilometers based on an absolute magnitude of 10.1.[10]

This minor planet was named from Greek mythology after the Trojan warrior Iphidamas, son of Theano and Antenor, who was the counselor of King Priam. During the Trojan War, he confronted Agamemnon in battle, but his spear bent against Agamemnon's war belt, who then killed Iphidamas with his sword.[1] The official naming citation was published by the Minor Planet Center on 27 June 1991 (M.P.C. 18465).[14]

  1. ^ a b Lightcurve plot of (4791) Iphidamas from Nov 2014 and Dec 2015 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.
  1. ^ a b c d e f g h "4791 Iphidamas (1988 PB1)". Minor Planet Center. Retrieved 20 June 2018.
  2. ^ Noah Webster (1884) A Practical Dictionary of the English Language
  3. ^ a b c d "JPL Small-Body Database Browser: 4791 Iphidamas (1988 PB1)" (2018-05-22 last obs.). Jet Propulsion Laboratory. Retrieved 20 June 2018.
  4. ^ a b "List of Jupiter Trojans". Minor Planet Center. 1 June 2018. Retrieved 20 June 2018.
  5. ^ a b "Asteroid (4791) Iphidamas – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 20 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. S2CID 119101711. (online catalog)
  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. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 20 June 2018.
  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. (online, AcuA catalog p. 153)
  9. ^ 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.
  10. ^ a b c d e f g "LCDB Data for (4791) Iphidamas". Asteroid Lightcurve Database (LCDB). Retrieved 20 June 2018.
  11. ^ a b Chatelain, Joseph P.; Henry, Todd J.; French, Linda M.; Winters, Jennifer G.; Trilling, David E. (June 2016). "Photometric colors of the brightest members of the Jupiter L5 Trojan cloud". Icarus. 271: 158–169. Bibcode:2016Icar..271..158C. doi:10.1016/j.icarus.2016.01.026.
  12. ^ 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.
  13. ^ 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.
  14. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 20 June 2018.