[en] The interstellar comet 2I/Borisov is the first interstellar object where compositional characterisation was possible throughout its entire perihelion passage. We report all 16 epochs of a comprehensive optical observation campaign with ESO Very Large Telescope's integral field spectrograph MUSE, spanning 126 days from 2019 November 14 to 2020 March 19. The spatial dust emission of 2I/Borisov was predominantly smooth, with no seasonal effect. A jetlike feature was consistently visible. The gas production morphology of its coma was also smooth and similar for C2, NH2, and CN: symmetric around the optocentre. The production rates of these species gently declined into and beyond perihelion, until 2I's outburst and splitting event in early 2020 March. C2, NH2, and CN production rates all increased, with NH2 being the most significant; the dust emission also slightly reddened. 2I/Borisov is a carbon-depleted, relatively NH2-rich comet when compared to those comets yet measured in the solar system.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Deam, Sophie E.; School of Physical and Chemical Sciences─Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand, Space Science and Technology Centre, School of Earth and Planetary Sciences, Curtin University, Perth, Western Australia 6845, Australia
Bannister, Michele T.; School of Physical and Chemical Sciences─Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
Opitom, Cyrielle; Royal Observatory Edinburgh
Knight, Matthew M.; Physics Department, United States Naval Academy, 572C Holloway Road, Annapolis, MD 21402, USA, University of Maryland, Department of Astronomy, College Park, MD 20742, USA
Ferellec, Léa; Royal Observatory Edinburgh
Ridden-Harper, Ryan; School of Physical and Chemical Sciences─Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
Seligman, Darryl Z.; Michigan State University, Department of Physics and Astronomy
Fitzsimmons, Alan; Queens University Belfast, School of Mathematics and Physics
Guilbert-Lepoutre, Aurélie; Laboratoire de Géologie de Lyon, LGL-TPE, UMR 5276 CNRS / Université de Lyon / Université Claude Bernard Lyon 1 / ENS Lyon, 69622 Villeurbanne, France
Jehin, Emmanuel ; Université de Liège - ULiège > Unités de recherche interfacultaires > Space sciences, Technologies and Astrophysics Research (STAR)
Yang, Bin; Instituto de Estudios Astrofísicos, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago, 8370191, Chile
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