Analysis of Hybrid Gas–Dust Outbursts Observed at 67P/Churyumov–Gerasimenko

Journal Article · Thu Jul 01 04:00:00 EDT 2021 · The Astronomical Journal (Online)

DOI:https://doi.org/10.3847/1538-3881/ABF8B4· OSTI ID:23159287

Noonan, John W.; Stern, S. Alan; Parker, Joel Wm.; Keeney, Brian A.; Steffl, Andrew J.; Schindhelm, Rebecca N. ^[1]; Rinaldi, Giovanna ^[2]; Feldman, Paul D. ^[3]; Bockelée-Morvan, Dominique ^[4]; Vervack, Jr., Ronald J.; Weaver, Harold A. ^[5]; Knight, Matthew M.; Feaga, Lori M.; A’Hearn, Michael F. ^[6]; Pineau, Jon ^[7]; Medina, Richard ^[8]; Bertaux, Jean-Loup ^[9]

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1. Department of Space Studies, Southwest Research Institute, Suite 300, 1050 Walnut Street, Boulder, CO 80302 (United States)
2. Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, via del Fosso del Cavaliere 100 I-00133 Rome (Italy)
3. Department of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States)
4. LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, F-92195 Meudon (France)
5. Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723-6099 (United States)
6. Astronomy Department, University of Maryland, College Park, MD 20742 (United States)
7. Stellar Solutions, Inc., Palo Alto, CA 94306 (United States)
8. Department of Space Operations, Southwest Research Institute, Suite 300, 1050 Walnut Street, Boulder, CO 80302 (United States)
9. LATMOS, CNRS/UVSQ/IPSL, 11 Boulevard d’Alembert, F-78280 Guyancourt (France)

Cometary outbursts offer a valuable window into the composition of comet nuclei with their forceful ejection of dust and volatiles in explosive events, revealing the interior components of the comet. Understanding how different types of outbursts influence the dust properties and volatile abundances, to better interpret what signatures can be attributed to primordial composition and what features are the result of processing, is an important task best undertaken with a multi-instrument approach. The European Space Agency Rosetta mission to 67P/Churyumov–Gerasimenko carried a suite of instruments capable of carrying out this task in the near-nucleus coma with unprecedented spatial and spectral resolution. In this work, we discuss two outbursts that occurred 2015 November 7 and were observed by three instruments on board: the Alice ultraviolet spectrograph, the Visual Infrared and Thermal Imaging Spectrometer, and the Optical, Spectroscopic, and Infrared Remote Imaging System. Together, the observations show that mixed gas and dust outbursts can have different spectral signatures representative of their initiating mechanisms, with the first outburst showing indicators of a cliff collapse origin and the second more representative of fresh volatiles being exposed via a deepening fracture. This analysis opens up the possibility of remote spectral classification of cometary outbursts with future work.

• OSTI ID: 23159287
• Journal Information: The Astronomical Journal (Online), Journal Name: The Astronomical Journal (Online) Journal Issue: 1 Vol. 162; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
79 ASTRONOMY AND ASTROPHYSICS
COMETS
NUCLEI
RESOLUTION
SPECTROMETERS
ULTRAVIOLET RADIATION
VOLATILITY