A Look at Eight Outbursts of Comet 7P/Pons-Winnecke

Ky Huynh; Michael S. P. Kelley; Jessica M. Sunshine; Quanzhi Ye; Tim Lister; Dennis Bodewits; Adam McKay; Megan E. Schwamb; Helen Usher

arXiv · 2606.25070

A Look at Eight Outbursts of Comet 7P/Pons-Winnecke

Ky Huynh·Michael S. P. Kelley·Jessica M. Sunshine·Quanzhi Ye·Tim Lister·Dennis Bodewits·Adam McKay·Megan E. Schwamb·Helen Usher

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Abstract

Cometary outbursts may be used as a means to infer the physical processes occurring on cometary nuclei. To that end, we studied eight outbursts of comet 7P/Pons-Winnecke identified between 2021 June 3 and 2021 August 31. The data analyzed consisted of optical images and derived photometry of the comet from the Las Cumbres Observatory network of telescopes. The outburst strengths relative to the ambient coma ranged from -0.2 to -1.1 mag, and the ejecta themselves had apparent brightnesses ranging from 17.4 to 13.3 mag. The morphologies of the ejecta varied, suggesting that the events may have originated from different sources across the nucleus. An order of magnitude estimation of the ejecta masses ranged from 10$^{5}$ - 10$^{6}$ kg, similar to other mini-outbursts of comets. The surface-area normalized outburst rate estimated during this time period is similar to comets 41P/Tuttle-Giacobini-Kresák, 9P/Tempel 1 and 46P/Wirtanen, but 10 times larger than that observed at comet 49P/Arend-Rigaux. However, a comparison to the mini-outburst rate of comet 67P/Churyumov-Gerasimenko reveals significant discrepancies between Rosetta spacecraft results and those from ground-based telescopes. We also investigate whether or not cometary outbursts from 7P in the 19th century are needed to explain outbursts in meteor shower rates observed in the 20th century.

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Ky Huynh, Michael S. P. Kelley, Jessica M. Sunshine, Quanzhi Ye, Tim Lister, Dennis Bodewits, Adam McKay, Megan E. Schwamb, Helen Usher. 2026-06-23. A Look at Eight Outbursts of Comet 7P/Pons-Winnecke. https://arxiv.org/abs/2606.25070

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