108P/Ciffréo Explained

108P/Ciffréo
Discovery Ref:[1]
Discoverer:Jacqueline Ciffréo
Discovery Date:8 November 1985
Designations:1985p, 1985 XVI, 1992s, 1993 I
Orbit Ref:[2]
Epoch:19 May 2018
Aphelion:5.759 AU
Perihelion:1.526 AU
Semimajor:3.642 AU
Eccentricity:0.581
Period:6.95 years
Inclination:13.980°
Asc Node:52.402°
Arg Peri:356.86°
Earth Moid:0.535 AU
Jupiter Moid:0.283 AU
Mean Diameter:3.2 km
1 km
M1:10.9
Last P:11 October 2021
Next P:2028-Dec-09[3]

108P/Ciffréo is a periodic comet with an orbital period of 7 years discovered by Jacqueline Ciffréo on November 8, 1985.[4] The comet is noted for having a peculiar double morphology, in which the nucleus is accompanied by a comoving, detached, diffuse tail, which is probably a perspective artifact of particles ejected sunwards and then repelled by solar wind.[5] [6]

The comet was discovered by Jacqueline Ciffréo on 8 November 1985 using a 0.9 m Schmidt camera at Caussols. The comet was then a diffuse object with an apparent magnitude of 10. H. Kosai from the Tokyo Observatory noticed on 9 November that it also had a faint tail about 1.5 arcminutes long.[1] An elliptical orbit was published by Daniel W. E. Green on 18 November, with an estimated orbital period of 7.81 years, while perihelion had taken place on 28 October 1985 at a distance of 1.72 AU.[7] Further observations revealed that the perihelion was on 30 October and the orbital period of the comet was 7.22 years.[4] On December 1985 a detacted coma or tail was detected 6 arcseconds from the nucleus of the comet and extending for 20 arcseconds to the north-east. The visual magnitude of the comet was estimated to be 12.5.[8]

The comet was recovered on 1992 September 24 by J. V. Scotti with the Spacewatch telescope. The comet passed perihelion on 23 January 1993. The next perihelion was in April 2000 and the comet was observed in November and December 1999 and November and December 2000.[4] During the 2014 and 2021 apparition the comet featured a detached coma, similar to that observed in 1985.[6] The peculiar morphology was attributed to a possible fragmentation event[9] but further observations revealed it is most probably an artifact of the turnaround of particles ejected sunward and repelled by sunlight.[5]

Notes and References

  1. Heudier . J. -L. . Ciffreo . J. . Kosai . H. . Comet Ciffreo (1985p) . International Astronomical Union Circular . 12 November 1985 . 4135 . 1 . 0081-0304.
  2. Web site: Small-Body Database Lookup: 108P/Ciffreo . ssd.jpl.nasa.gov . 26 March 2023.
  3. Web site: Horizons Batch for 108P/Ciffreo (90000970) on 2028-Dec-09 . . Perihelion occurs when rdot flips from negative to positive . 2023-04-29. (Soln.date: 2022-Aug-16)
  4. Web site: Kronk . Gary . 108P/Ciffreo . cometography.com . 26 March 2023.
  5. Kim . Yoonyoung . Jewitt . David . Luu . Jane . Li . Jing . Mutchler . Max . Comet 108P/Ciffreo: The Blob . The Astronomical Journal . 1 April 2023 . 165 . 4 . 150 . 10.3847/1538-3881/acba07 . 2302.03697 . free .
  6. Manzini . Federico . Ochner . Paolo . Oldani . Virginio . Bedin . Luigi R. . Reguitti . Andrea . Bosch . Jean Gabriel . Soulier . Jean François . Comet C/108P (Ciffreo) is not splitting . The Astronomer's Telegram . 25 January 2022 . 15177 . 1 .
  7. Green . Daniel . IAUC 4137: 1985p; CH Cyg; MU Cep . Central Bureau for Astronomical Telegrams . 18 November 1985 .
  8. Marsden . Brian . IAUC 4158: PLUTO; 1985p . Central Bureau for Astronomical Telegrams . 3 January 1986 .
  9. Jewitt . David . Agarwal . Jessica . Kim . Yoonyoung . Li . Jing . Mutchler . Max . Disintegrating Comet 108P/Ciffreo . HST Proposal . 1 January 2022 . 16904 . 2022hst..prop16904J .