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Abstract We report the discovery of recurrent activity on quasi-Hilda comet (QHC) 362P/(457175) 2008 GO98. The first activity epoch was discovered during the perihelion passage of 362P in 2016, so we were motivated to observe it for recurrent cometary activity near its next perihelion passage (UT 2024 July 20). We obtained observations with the Lowell Discovery Telescope, the Astrophysical Research Consortium telescope, and the Vatican Advanced Technology Telescope and identified a second activity epoch when 362P had a true anomaly (ν) as early as 318 1. We conducted archival searches of six repositories and identified images obtained with Canada–France–Hawaii Telescope MegaCam, Dark Energy Camera, Pan-STARRS 1, SkyMapper, Zwicky Transient Facility, and Las Cumbres Observatory Global Telescope network data. Using these data, we identified activity from a previously unreported time span, and we did not detect activity when 362P was away from perihelion, specifically 83∘<ν< 318∘. Detection of activity near perihelion and absence of activity away from perihelion suggest thermally driven activity and volatile sublimation. Our dynamical simulations suggest 362P is a QHC, and it will remain in a combined Jupiter-family comet (JFC) and quasi-Hilda orbit over the next 1 kyr though it will become increasingly chaotic nearing the end of this timeframe. Our reverse simulations suggest 362P may have migrated from the orbit of a long-period comet (∼53%) or Centaur (∼32%); otherwise it remained a JFC (∼15%) over the previous 100 kyr. We recommend additional telescope observations from the community as 362P continues outbound from its perihelion on UT 2024 July 20, as well as continued observations for a third activity epoch.
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This content will become publicly available on June 6, 2026
A Dormant Captured Oort Cloud Comet Awakens: (18916) 2000 OG 44
Abstract We report the discovery of activity emanating from (18916) 2000 OG44(alternately designated 1977 SD), a minor planet previously reported to be both an extinct comet and an asteroid on a cometary orbit. We observed 2000 OG44with a thin tail oriented towards the coincident antisolar and antimotion vectors (as projected on the sky) in images we acquired on UT 2023 July 24 and 26 with the Apache Point Observatory 3.5 m Astrophysical Research Consortium telescope (New Mexico, USA). We also include observations made in Arizona with the Vatican Advanced Technology Telescope at the Mount Graham International Observatory and the Lowell Observatory Lowell Discovery Telescope near Happy Jack. We performed dynamical simulations that reveal 2000 OG44most likely originated in the Oort cloud, arriving within the last 4 Myr. We find 2000 OG44, which crosses the orbits of both Jupiter and Mars, is at present on an orbit consistent with a Jupiter-family comet. We carried out thermodynamical modeling that informed our broader diagnosis that the observed activity is most likely due to volatile sublimation.
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- PAR ID:
- 10610703
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 986
- Issue:
- 1
- ISSN:
- 2041-8205
- Page Range / eLocation ID:
- L2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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