156P/Russell–LINEAR

156P/Russell–LINEAR
	Comet 156P/Russell–LINEAR on 9 December 2020 by NEOWISE
Discovery
Discovered by	Kenneth S. Russell
Discovery date	September 1986
Designations
Alternative designations	P/1986 R1, 1993 WU, 2000 QD181, 2000 XV43
Orbital characteristics
Epoch	20 March 2020
Aphelion	5.591 AU
Perihelion	1.333 AU
Semi-major axis	3.462 AU
Eccentricity	0.615
Orbital period	6.44 years
Inclination	15.264°
Longitude of; ascending node	35.397°
Argument of; periapsis	0.38°
Last perihelion	18 November 2020
Next perihelion	2027-Apr-30
Earth MOID	0.339 AU
Jupiter MOID	0.100 AU
Comet total; magnitude (M1)	12.7

156P/Russell–LINEAR is a Jupiter family periodic comet with an orbital period of 6.4 years. It was discovered by Kenneth S. Russell in September 1986.^[5]

Observational history

The comet was found by Australian astronomer Kenneth S. Russell in September 1986 on a plate exposed on 3 September 1986 using the U.K. Schmidt Telescope of Siding Spring Observatory, Australia.^[5] The comet had an apparent magnitude of 17. Follow up observations on 25 September failed to recover the comet.^[1] The comet was spotted again in a plate exposed using the 0.46-m Schmidt telescope of Palomar Observatory by Carolyn S. Shoemaker on 19 November 1993. The comet had asteroidal appearance and was given the provisional designation 1993 WU.^[1]

The comet was observed again during the 2000 perihelion. The comet was noted as an asteroidal object by Lincoln Near-Earth Asteroid Research on 31 August and 5 November and was given the provisional designation 2000 QD₁₈₁, and was observed again in November 2000-January 2001 and named 2000XV₄₃. Timothy B. Spahr noted that these objects were the same as the 1986 comet.^[1] It was then given the number 156.^[6]

The comet had passed 0.70 AU from Jupiter in November 1970 and its perihelion distance decreased from 1.73 AU to 1.56 AU. The comet approached again to Jupiter in March 2018 at a distance of 0.36 AU and its perihelion distance decreased to 1.33 AU, while the orbital period decreased from 6.85 years to 6.44 years.^[5]^[4]

During the 2020 perihelion, the comet approached to 0.48 AU from Earth on 24 October 2020.^[5] It brightened to an apparent magnitude of 9.7 in mid November 2020.^[7] The cyanide and diatomic carbon production rate was estimated to be (2.85±0.51)×10²⁴ mol/s and (3.44±0.62)×10²⁴ mol/s respectively on 14 October 2020, when the comet was located at an heliocentrical distance of 1.40 AU.^[8] The production rates are comparable to that of other Jupiter-family comets. Two strong jets were observed during perihelion and persisted until December, indicating increased activity after perihelion.^[9]

The nucleus radius is estimated to be less than 2.0 ± 0.2 km.^[10]

References

^ ^a ^b ^c ^d Green, Daniel (19 April 2003). "P/2000 QD_181 = 1986 R1 = 1993 WU". International Astronomical Union Circular (8118): 1.
^ "156P/Russell-LINEAR Orbit". Minor Planet Center.
^ "Horizons Batch for 156P/Russell-LINEAR (90001084) on 2027-Apr-30" (Perihelion occurs when rdot flips from negative to positive). JPL Horizons. Retrieved 2023-07-06. (JPL#48/Soln.date: 2023-May-03)
^ ^a ^b ^c "Small-Body Database Lookup: 156P/Russell-LINEAR". ssd.jpl.nasa.gov. Retrieved 26 March 2023.
^ ^a ^b ^c ^d Kronk, Gary. "C&MS: 156P/Russell-LINEAR". cometography.com. Retrieved 20 May 2023.
^ Green, D. W. E (1 May 2003). "Comet 156P/Russell-LINEAR". International Astronomical Union Circular (8128): 3. ISSN 0081-0304.
^ Yoshida, Seiichi. "Weekly Information about Bright Comets (2020 Nov. 28: North)". www.aerith.net. Retrieved 20 May 2023.
^ "ATel #14101: TRAPPIST comet production rates: 88/Howell, C/2020 M3 (ATLAS), C/2020 S3 (Erasmus), 156P/Russell-LINEAR". The Astronomer's Telegram. 16 October 2020. Retrieved 20 May 2023.
^ Aravind, K.; Halder, Prithish; Ganesh, Shashikiran; Sahu, Devendra; Serra-Ricart, Miquel; Chambó, José J.; Angchuk, Dorje; Sivarani, Thirupathi (September 2022). "Optical observations and dust modelling of comet 156P/Russell-LINEAR". Icarus. 383: 115042. arXiv:2204.09727. doi:10.1016/j.icarus.2022.115042.
^ Gillan, A. Fraser; Fitzsimmons, Alan; Denneau, Larry; Siverd, Robert J.; Smith, Ken W.; Tonry, John L.; Young, David R. (1 January 2024). "Dust Production Rates in Jupiter-family Comets: A Two Year Study with ATLAS Photometry". The Planetary Science Journal. 5 (1): 25. arXiv:2312.06817. doi:10.3847/PSJ/ad1394.