(316179) 2010 EN65 is a trans-Neptunian object orbiting the Sun. However, with a semi-major axis of 30.8 AU, the object is actually a jumping Neptune trojan, co-orbital with Neptune, as the giant planet has a similar semi-major axis of 30.1 AU. The body is jumping from the Lagrangian point L4 into L5 via L3.[4] As of 2016, it is 54 AU from Neptune. By 2070, it will be 69 AU from Neptune.[7]

(316179) 2010 EN65
2010 EN65 is jumping from L4 to L5 via L3.
Discovery[1][2]
Discovered byD. L. Rabinowitz
S. W. Tourtellotte
Discovery siteLa Silla Obs.
Discovery date7 March 2010
Designations
(316179) 2010 EN65
TNO[3] · Neptune trojan[4]
distant[2]
Orbital characteristics[3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 2
Observation arc25.45 yr (9,296 days)
Aphelion40.367 AU
Perihelion21.148 AU
30.758 AU
Eccentricity0.3124
170.58 yr (62,306 days)
48.107°
0° 0m 20.88s / day
Inclination19.209°
234.47°
225.77°
Physical characteristics
176 km (est. at 0.08)[5][6]
7.17[3]

Discovery

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2010 EN65 was discovered on 7 March 2010, by David L. Rabinowitz and Suzanne W. Tourtellotte using the 1.3-meter Small and Medium Research Telescope System (SMARTS) at Cerro Tololo Observatory in Chile.[1]

Orbit

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2010 EN65 follows a rather eccentric orbit (0.31) with a semi-major axis of 30.72 AU and an inclination of 19.3º.[3] Its orbit is well determined with images dating back to 1989.

 
Animation of 2010 EN65 relative to Sun and Neptune 1600-2398
  2010 EN65 ·   Neptune ·   Sun

Physical properties

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2010 EN65 is a quite large minor body with an absolute magnitude of 7.17 and an estimated diameter of 176 kilometers (109 miles) based on an assumed albedo of 0.08.[5][6]

Jumping trojan

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2010 EN65 is another co-orbital of Neptune, the second brightest after the quasi-satellite (309239) 2007 RW10. 2010 EN65 is currently transitioning from librating around Lagrangian point L4 to librating around L5.[4] This unusual trojan-like behavior is termed "jumping trojan".[8]

Numbering and naming

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This minor planet was numbered by the Minor Planet Center on 7 February 2012 (M.P.C. 78220).[9] As of 2021, it has not been named.[2] If named, it will follow the naming scheme already established with 385571 Otrera and 385695 Clete, which is to name these objects after figures related to the Amazons, an all-female warrior tribe that fought in the Trojan War on the side of the Trojans against the Greek.[10]

References

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  1. ^ a b Lowe, A.; Helin, E. F.; Pravdo, S.; Lawrence, K.; Hicks, M.; Thicksten, R.; Rabinowitz, D.; Tourtellotte, S.; Marsden, B. G. (7 May 2010). "2010 EN65". Minor Planet Electronic Circular. 2010-J33.
  2. ^ a b c "316179 (2010 EN65)". Minor Planet Center. Retrieved 25 February 2018.
  3. ^ a b c d "JPL Small-Body Database Browser: 316179 (2010 EN65)" (2015-04-18 last obs.). Jet Propulsion Laboratory. Retrieved 25 February 2018.
  4. ^ a b c de la Fuente Marcos, C.; de la Fuente Marcos, R. (November 2012). "Four temporary Neptune co-orbitals: (148975) 2001 XA255, (310071) 2010 KR59, (316179) 2010 EN65, and 2012 GX17". Astronomy and Astrophysics. 547: 7. arXiv:1210.3466. Bibcode:2012A&A...547L...2D. doi:10.1051/0004-6361/201220377. S2CID 118622987. Retrieved 7 September 2016. (rotating frame)
  5. ^ a b Johnston, Wm. Robert (18 August 2020). "List of Known Trans-Neptunian Objects". Johnston's Archive. Retrieved 23 July 2021.
  6. ^ a b "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 23 July 2021.
  7. ^ 2010 EN65 at JPL Horizons Change "Observer Location" to @Neptune
  8. ^ Tsiganis, K.; Dvorak, R.; Pilat-Lohinger, E. (February 2000). "Thersites: a 'jumping' Trojan?". Astronomy and Astrophysics. 354: 1091–1100. Bibcode:2000A&A...354.1091T.
  9. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 23 July 2021.
  10. ^ Ticha, J.; et al. (10 April 2018). "DIVISION F / Working Group for Small Body Nomenclature Working Group for Small Body Nomenclature. THE TRIENNIAL REPORT (2015 Sept 1 - 2018 Feb 15)" (PDF). IAU. Retrieved 25 August 2018.
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