7119 Hiera

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7119 Hiera
Discovery [1]
Discovered by C. Shoemaker
E. Shoemaker
Discovery site Palomar Obs.
Discovery date 11 January 1989
Designations
MPC designation (7119) Hiera
Pronunciation /ˈhərə/ HYE-ər-ə
Named after
Hiera (Greek mythology)[2]
1989 AV2
Jupiter trojan[3][4]
(Greek camp)[5]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 29.53 yr (10,786 days)
Aphelion 5.6780 AU
Perihelion 4.6287 AU
5.1534 AU
Eccentricity 0.1018
11.70 yr (4,273 days)
209.38°
0° 5m 3.12s / day
Inclination 19.314°
285.52°
120.98°
Jupiter MOID 0.1935 AU
Jupiter Tisserand parameter 2.8780
Physical characteristics
Dimensions 59.15±0.37 km[6]
59.150±0.375[7]
76.40±7.0 km (IRAS:2)[1]
76.45 km (derived)[4]
77.29±4.66 km[8]
400 h[9]
0.036±0.005[8]
0.0364±0.008 (IRAS:2)[1]
0.0398 (derived)[4]
0.067±0.010[6][7]
C[4]
9.7[1][4][6] · 9.80[8] · 9.82±0.37[10]

7119 Hiera (/ˈhərə/ HYE-ər-ə), provisional designation 1989 AV2, is a carbonaceous Jupiter trojan and potentially slow rotator from the Greek camp, approximately 76 kilometers in diameter.

It was discovered on 11 January 1989, by American astronomer couple Carolyn and Eugene Shoemaker at Palomar Observatory in California, United States.[3] The Jovian asteroid was named for Hiera from Greek mythology.[2]

Orbit and classification[edit]

Hiera resides in the leading Greek camp at Jupiter's L4 Lagrangian point, 60° ahead of the gas giant's orbit (see Trojans in astronomy). It orbits the Sun in the outer main-belt at a distance of 4.6–5.7 AU once every 11 years and 8 months (4,273 days). Its orbit has an eccentricity of 0.10 and an inclination of 19° with respect to the ecliptic.[1] A first precovery was taken at the discovering observatory in 1987, extending the body's observation arc by 14 months prior to its official discovery observation at Palomar.[3]

Physical characteristics[edit]

Suspected slow rotator[edit]

In June 2009, Hiera was observed by Italian astronomer Stefano Mottola at the Spanish Calar Alto Observatory during 5 consecutive nights. Although a lightcurve could not be obtained and a systematic instrumental error could not be ruled out, the body displayed a slowly, ever decreasing brightness of 0.1 in magnitude, which would translate into a rotation period of at least 400 hours (U=1).[9] This would make Hiera a slow rotator.

Diameter and albedo[edit]

According to the space-based 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, Hiera measures between 56 and 77 kilometers in diameter and its surface has an albedo between 0.036 and 0.072.[1][7][6][8] The Collaborative Asteroid Lightcurve Link agrees with the results obtained by IRAS, and derives an albedo for carbonaceous asteroids of 0.0389 with a diameter of 76.5 kilometers with an absolute magnitude of 9.7.[4]

Naming[edit]

This minor planet was named after Hiera from Greek mythology, a female general in the Trojan war. However, her name was removed from Homer's Iliad, as to not diminish the greatness of Helen of Troy, the daughter of Zeus and cause for the Trojan war (also see 101 Helena). The official naming citation was published by the Minor Planet Center on 4 May 1999 (M.P.C. 34625).[11] Although the asteroid resides in the Greek camp, the citation describes Hiera as a general of the Mysians, who fought on the Trojan, not the Greek side in the Trojan War.

References[edit]

  1. ^ a b c d e f g "JPL Small-Body Database Browser: 7119 Hiera (1989 AV2)" (2017-06-03 last obs.). Jet Propulsion Laboratory. Retrieved 21 June 2017. 
  2. ^ a b Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (7119) Hiera. Springer Berlin Heidelberg. p. 577. ISBN 978-3-540-00238-3. Retrieved 10 July 2016. 
  3. ^ a b c "7119 Hiera (1989 AV2)". Minor Planet Center. Retrieved 10 July 2016. 
  4. ^ a b c d e f "LCDB Data for (7119) Hiera". Asteroid Lightcurve Database (LCDB). Retrieved 4 August 2016. 
  5. ^ "List of Jupiter Trojans". Minor Planet Center. 20 June 2016. Retrieved 4 August 2016. 
  6. ^ 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". The Astrophysical Journal. 741 (2): 25. Bibcode:2011ApJ...741...90M. arXiv:1109.6407Freely accessible. doi:10.1088/0004-637X/741/2/90. Retrieved 10 July 2016. 
  7. ^ a b c 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. Bibcode:2012ApJ...759...49G. arXiv:1209.1549Freely accessible. doi:10.1088/0004-637X/759/1/49. Retrieved 5 December 2016. 
  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. Retrieved 10 July 2016. 
  9. ^ 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 10 July 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. Bibcode:2015Icar..261...34V. arXiv:1506.00762Freely accessible. doi:10.1016/j.icarus.2015.08.007. Retrieved 10 July 2016. 
  11. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 10 July 2016. 

External links[edit]