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arXiv · 1911.08318

First Results from TESS Observations of Comet 46P/Wirtanen

Tony L. Farnham·Michael S. P. Kelley·Matthew M. Knight·Lori M. Feaga
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Abstract

We report on initial results from 20 days' worth of TESS spacecraft observations of comet 46P/Wirtanen. The long-duration, high-cadence measurements show a 2018 September 26 outburst that exhibited a two-phase, 0.5 mag brightening profile, and may be the best temporally characterized natural outburst ever recorded. Gas velocities from the outburst peaked at 800 m s$^{-1}$, while dust expanded at only 10s of m s$^{-1}$. Coadded images also revealed a previously unreported dust trail that extends beyond the 24$^\circ$ field of view.

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Tony L. Farnham, Michael S. P. Kelley, Matthew M. Knight, Lori M. Feaga. 2019-11-19. First Results from TESS Observations of Comet 46P/Wirtanen. https://doi.org/10.3847/2041-8213%2Fab564d

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