BAA Comet Section Periodic Comets

BAA Comet Section : Periodic Comets 500 - 599

Updated 2025 February 28

P/LINEAR = 2015 CD60
An asteroid was discovered by the Space Surveilance Telescope at the Atom site [a successor to LINEAR] on 2015 February 13.11 at 20th magnitude. There were pre-discovery images with the earliest from PanSTARRS on 2014 November 25. It was at perihelion in 2015 February at 2.0 au and has a period of 9.9 years. It was classed as an outer main belt asteroid.

On 2024 December 8, Roberto Haver reported (comets-ml) having detected a tail in images taken on December 2. Alan Hale confirmed the tail on December 21. A month later the MPC issued MPEC 2025 A-142 [2025 January 8] CBET 5489 gives more details of the original discovery and the 2024 re-discovery. It was at perihelion in 2024 December.

P/Catalina = 2019 Y3 = 2025 A5
A possible comet of 18th magnitude was discovered in Catalina Sky Survey images taken with the 0.68m Schmidt on 2019 December 17.53. It was was placed on the PCCP as C0TUEG1 and confirmed by other observers including Michael Jaeger. [CBET 4711, MPEC 2020-A109, 2020 January 9]. The comet was near perihelion at 0.9 au in 2019 December and has a period of around 5 years.

PanSTARRS 1 accidentally recovered 2019 Y3 on 2025 January 7.22 at 19th magnitude. It was briefly posted on the PCCP as P125u6N, then removed without people noticing. Further reports also made it to the PCCP as A11hRte (January 20), A11hVVH (January 21) and C44DR81 (February 3). Michael Jaeger also made an independent recovery on January 29.8 that was reported to the CBET. [MPEC 2025-C161, CBET 5504, 2025 February 11/12] The recovery indicates a correction of Delta(T) = +1.37 days to previous predictions. The comet reaches perihelion at 0.9 au in March. The comet will pass 0.34 au from the earth on 2025 March 18 and 0.33 au from Jupiter on 2033 July 4. The comet passed 0.072 au from Venus in 1958 and 0.11 au from Jupiter in 1926. It is an intrinsically faint object that is only predicted to reach 16th magnitude during the approach, which is favourable for northern hemisphere observers.

P/PANSTARRS = 2019 A8 = 2025 B3
A 21st magnitude comet was discovered in PanSTARRS 1 images taken with the 1.8m Ritchey-Chretien on 2019 January 11.64. It was placed on the PCCP as P10LqGV. [CBET 4608, MPEC 2019-C20, 2019 February 4] The comet currently has a period of around 5.9 years and was at perihelion at 1.9 au in 2018 August.

2019 A8 was accidentally recovered in images taken images taken with the 1.5-m reflector of the Mt Lemmon Survey on January 24.39 at 21st magnitude. Michael Jaeger et al also made an independent recovery on February 22. [MPEC 2025-D234, CBET 5516, 2025 February 27/28] The relatively short arc, combined with a close approach to Jupiter gave rise to a Delta(T) of +49.2 days for the time of perihelion compared to previous predictions. The comet made close approaches of 0.3 au to Jupiter in 2009 November and 2021 November. It now has a period of 6.3 years and is at perihelion at 2.1 au in 2025 March.

P/Rankin = 2024 L4 = 2014 N4 = 2017 B6
David Rankin discovered a comet of 21st magnitude in images taken with the 1.5-m reflector of the Mt Lemmon Survey on June 15.43. It was posted on the PCCP as CAPN0N2. [MPEC 2024-N106, CBET 5409, 2024 July 9]. The comet was at perihelion at 0.7 au in 2024 April and has a period of 3.33 years. Sam Deen on the comets-ml notes that it is a very unusual object. It has the smallest aphelion distance on record, is in a stable orbit and is intrinsically faint. He suggests that it may be a recent rotational disintegration, or impacted object as he could not find it in ZTF images from early May, which would explain the reported condensed coma. Peter Jenniskens notes that there is a possible associated meteor shower, the delta1 Canis Minorids.

Sam Deen subsequently found pre-discovery images from PanSTARRS taken on 2014 July 4.58, with other images from NEOWISE on January 31 and the CFHT on July 18. The comet was designated 2014 N4 for the return. He then found images from Suburu taken on 2017 January 21.23, 23 and 26, and 2016 December 23 and the comet was designated 2017 B6 for this return. He also found images taken by the CFHT on 2004 August 19, but for some reason it was not given a designation at this return.

When observing a comet please try to forget how bright you think the comet should be, what it was when you last viewed it, what other observers think it is or what the ephemeris says it should be.

The order given here is provisional and based on the logical sequence of linked orbits. The final numbering scheme does not seem to follow this logical pattern.

Published by Jonathan Shanklin. Jon Shanklin - jds@ast.cam.ac.uk