117P/Helin–Roman–Alu, also known as Helin-Roman-Alu 1, is a periodic comet in the Solar System. It is a Quasi-Hilda comet.[4]
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Discovery | |
---|---|
Discovered by | Eleanor F. Helin Brian P. Roman Jeff Alu |
Discovery date | October 2, 1989 |
Designations | |
1987 XXXVII | |
Orbital characteristics | |
Epoch | March 6, 2006 |
Aphelion | 5.123 AU |
Perihelion | 3.037 AU |
Semi-major axis | 4.08 AU |
Eccentricity | 0.2556 |
Orbital period | 8.24 a |
Inclination | 8.7080° |
Last perihelion | 2022-Jul-07[1] March 27, 2014[2] December 19, 2005 |
Next perihelion | 2030-Nov-26[3] |
References
edit- ^ "117P/Helin-Roman-Alu Orbit". Minor Planet Center. Retrieved 2014-06-17.
- ^ Syuichi Nakano (2011-04-06). "117P/Helin-Roman-Alu 1 (NK 2051)". OAA Computing and Minor Planet Sections. Retrieved 2012-02-20.
- ^ "Horizons Batch for 117P/Helin-Roman-Alu 1 (90001003) on 2030-Nov-26" (Perihelion occurs when rdot flips from negative to positive). JPL Horizons. Retrieved 2023-07-06. (JPL#K222/63 Soln.date: 2023-Jul-06)
- ^ Toth, I. (March 2006). "The quasi-Hilda subgroup of ecliptic comets - an update". Astronomy and Astrophysics. 448 (3): 1191–1196. Bibcode:2006A&A...448.1191T. doi:10.1051/0004-6361:20053492.
External links
edit- Orbital simulation from JPL (Java) / Horizons Ephemeris
- 117P/Helin-Roman-Alu 1 – Seiichi Yoshida @ aerith.net
- Elements and Ephemeris for 117P/Helin-Roman-Alu – Minor Planet Center
- 117P at Kronk's Cometography
- Images of 117P by Roger Groom