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References
- 1 2 3 4 5 6 7 "(343158) Marsyas". Minor Planet Center. Retrieved 18 May 2021.
- 1 2 3 "MPEC 2009-J04 : 2009 HC82". IAU Minor Planet Center. 1 May 2009. Retrieved 18 May 2021.
- 1 2 3 "WGSBN Bulletin Archive". Working Group for Small Bodies Nomenclature. 14 May 2021. Retrieved 16 May 2021. (Bulletin #1)
- 1 2 3 4 5 "JPL Small-Body Database Browser: 343158 Marsyas" (2021-05-18 last obs.). Jet Propulsion Laboratory . Retrieved 18 May 2021.
- 1 2 3 "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 26 January 2018.
- ↑ "Date/Time Removed". NASA/JPL Near-Earth Object Program Office. Archived from the original on 2 June 2002. Retrieved 19 March 2012.
- ↑ "NEO Close-Approaches (Between 1900 and 2200)". NASA/JPL Near-Earth Object Program. Archived from the original on 13 December 2012. Retrieved 22 June 2012. (sorted by descending relative velocity, dist<0.5AU = "215,221 close-Earth approaches")
- 1 2 3 "JPL Close-Approach Data: (2009 HC82)" (last observation: 2010-04-04). Retrieved 9 February 2011.
- ↑ "JPL Close-Approach Data: 1P/Halley" (last observation: 1994-01-11). Retrieved 9 February 2011.
- ↑ "JPL Close-Approach Data: 55P/Tempel-Tuttle" (last observation: 1998-07-05). Retrieved 9 February 2011.
- ↑ Akimasa Nakamura and bas (2 May 2009). "List of Damocloids (Oort cloud asteroids)". Lowell Observatory. Retrieved 9 February 2011.
- 1 2 Greenstreet, Sarah; Ngo, Henry; Gladman, Brett (January 2012). "The orbital distribution of Near-Earth Objects inside Earth's orbit" (PDF). Icarus. 217 (1): 355–366. Bibcode:2012Icar..217..355G. doi:10.1016/j.icarus.2011.11.010. hdl:2429/37251.
There are two known retrograde NEAs: 2007 VA85 (a = 4.226 AU, e = 0.736, i = 131.769°) and 2009 HC82 (a = 2.528 AU, e = 0.807, i = 154.519°).
- 1 2 Greenstreet, Sarah; Gladman, Brett; Ngo, Henry; Granvik, Mikael; Larson, Steve (April 2012). "Production of near-Earth asteroids on retrograde orbits" (PDF). The Astrophysical Journal Letters. 749 (2): L39–L43. Bibcode:2012ApJ...749L..39G. doi:10.1088/2041-8205/749/2/L39. S2CID 121886308.
2009 HC82, on the other hand, is on an orbit very near the 3:1 resonance (where it most likely flipped) for the entirety of both independent 1 Myr integrations of the best-fit orbit. This behavior is exactly like the typical steady-state retrograde NEA evolution we discovered.
