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Abstract We have discovered two epochs of activity on quasi-Hilda 2009 DQ118. Small bodies that display comet-like activity, such as active asteroids and active quasi-Hildas, are important for understanding the distribution of water and other volatiles throughout the solar system. Through our NASA Partner Citizen Science project, Active Asteroids, volunteers classified archival images of 2009 DQ118as displaying comet-like activity. By performing an in-depth archival image search, we found over 20 images from UT 2016 March 8–9 with clear signs of a comet-like tail. We then carried out follow-up observations of 2009 DQ118using the 3.5 m Astrophysical Research Consortium Telescope at Apache Point Observatory, Sunspot, New Mexico, USA and the 6.5 m Magellan Baade Telescope at Las Campanas Observatory, Chile. These images revealed a second epoch of activity associated with the UT 2023 April 22 perihelion passage of 2009 DQ118. We performed photometric analysis of the tail and find that it had a similar apparent length and surface brightness during both epochs. We also explored the orbital history and future of 2009 DQ118through dynamical simulations. These simulations show that 2009 DQ118is currently a quasi-Hilda and that it frequently experiences close encounters with Jupiter. We find that 2009 DQ118is currently on the boundary between asteroidal and cometary orbits. Additionally, it has likely been a Jupiter family comet or Centaur for much of the past 10 kyr and will be in these same regions for the majority of the next 10 kyr. Since both detected epochs of activity occurred near perihelion, the observed activity is consistent with sublimation of volatile ices. 2009 DQ118is currently observable until ∼mid-October 2023. Further observations would help to characterize the observed activity.
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Comet-like Activity Discovered on Quasi-Hilda Asteroid 2009 DQ118
Abstract We report evidence of comet-like activity on asteroid 2009 DQ118, a quasi-Hilda object near the 3:2 interior mean-motion resonance with Jupiter. This discovery was made by volunteers as part of the Active Asteroids Citizen Science project, a NASA Partner hosted on the Zooniverse platform. Follow-up archival searches yielded over 20 images of 2009 DQ118 exhibiting a comet-like tail on UT 2016 March 8 and 9 acquired with the Dark Energy Camera on the Blanco 4 m telescope at the Cerro Tololo Inter-American Observatory, Chile. These images were taken when 2009 DQ118 was near its 2016 perihelion passage. 2009 DQ118 will next reach perihelion on UT 2023 April 22; hence, the next several months are an excellent time to observe 2009 DQ118 to search for a second epoch of activity for this object.
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- Award ID(s):
- 1950901
- PAR ID:
- 10400634
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- Research Notes of the AAS
- Volume:
- 7
- Issue:
- 3
- ISSN:
- 2515-5172
- Format(s):
- Medium: X Size: Article No. 42
- Size(s):
- Article No. 42
- Sponsoring Org:
- National Science Foundation
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