The 2016 Feb 19 outburst of comet 67P/CG: an ESA Rosetta multi-instrument study

Eberhard Grün (1, 2) , Jessica Agarwal (3) , Nicolas Altobelli (4) , Kathrin Altwegg (5) , Mark Stephen Bentley (6) , Nicolas Biver (7) , Vincenzo Della Corte (8) , Niklas J. T. Edberg (9) , P. D. Feldman (10) , M. Galand (11) , B. Geiger (4) , C. Götz (12) , B. Grieger (4) , Carsten Güttler (3) , Pierre Henri (13) , M. Hofstadter (14) , M. Horanyi (2) , E. Jehin (15) , H. Krüger (3) , S. Lee (14) , T. Mannel (6) , E. Morales (16) , O. Mousis (17) , M. Müller (18) , C. Opitom (15) , Alessandra Rotundi (8, 19) , R. Schmied (20, 6) , F. Schmidt (21) , Holger Sierks (3) , C. Snodgrass (22) , R. H. Soja (21) , M. Sommer (21) , R. Srama (21) , C.-Y. Tzou (5) , Jean-Baptiste Vincent (3) , P. Yanamandra-Fisher (23) , Michael F. A'Hearn (24) , A. I. Erikson (9) , Cesare Barbieri (25) , M. A. Barucci (7) , Jean-Loup Bertaux (26) , I. Bertini (27) , J. Burch (28) , Luigi Colangeli (29) , Gabriele Cremonese (30) , V. da Deppo (31) , Björn Davidsson (32) , S. Debei (33) , M. de Cecco (34) , J. Deller (3) , L. M. Feaga (24) , M. Ferrari (8) , Sonia Fornasier (7) , Marco Fulle (34) , Adeline Gicquel (3) , M. Gillon (15) , S. F. Green (22) , O. Groussin (17) , Pedro J. Gutiérrez (35) , M. Hofmann (3) , S. F. Hviid (36) , W.-H. Ip (37) , S. Ivanovski (8) , L. Jorda (17) , H. U. Keller (12) , Matthew M. Knight (24) , J. Knollenberg (36) , Detlef Koschny (29) , J.-R. Kramm (3) , Ekkehard Kührt (36) , M. Küppers (38) , P. L. Lamy (17) , L. M. Lara (35) , M. Lazzarin (25) , J. J. Lòpez-Moreno (35) , J. Manfroid (15) , Elena Mazzotta Epifani (39) , F. Marzari (25) , G. Naletto (27, 40, 31) , N. Oklay (3) , P. Palumbo (8, 19) , J. Wm. Parker (41) , Hans Rickman (42, 32) , Rafael Rodrigo (43, 4) , J. Rodrìguez (35) , E. Schindhelm (44) , X. Shi (3) , R. Sordini (8) , A. J. Steffl (44) , S. A. Stern (44) , Nicholas Thomas (5) , Cécilia Tubiana (3) , H. A. Weaver (45) , Paul R. Weissman (46) , Vladimir V. Zakharov (47, 7) , M. G. G. T. Taylor (29)

1 MPIK - Max-Planck-Institut für Kernphysik
2 LASP - Laboratory for Atmospheric and Space Physics [Boulder]
3 MPS - Max-Planck-Institut für Sonnensystemforschung
4 ESAC - European Space Astronomy Centre
5 Physikalisches Institut [Bern]
6 IWF - Space Research Institute of Austrian Academy of Sciences
7 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
8 IAPS - Istituto di Astrofisica e Planetologia Spaziali - INAF
9 IRF - Swedish Institute of Space Physics [Uppsala]
10 Department of Physics and Astronomy [Baltimore]
11 Imperial College London
12 IGEP - Institut für Geophysik und Extraterrestrische Physik [Braunschweig]
13 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
14 JPL - Jet Propulsion Laboratory
15 Institut d'Astrophysique et de Géophysique [Liège]
16 Jaicoa Observatory
17 LAM - Laboratoire d'Astrophysique de Marseille
18 ESOC - European Space Operations Center
19 PARTHENOPE - Università degli Studi di Napoli “Parthenope” = University of Naples
20 Institute of Physics [Graz]
21 IRS - Institut für Raumfahrtsysteme
22 School of Physical Sciences [Milton Keynes]
23 SSI - Space Science Institute [Boulder]
24 Department of Astronomy [College Park]
25 Dipartimento di Fisica e Astronomia "Galileo Galilei"
26 PLANETO - LATMOS
27 CISAS - Centro di Ateneo di Studi e Attività Spaziali “Giuseppe Colombo”
28 Space Science Division [San Antonio]
29 ESTEC - European Space Research and Technology Centre
30 OAPD - INAF - Osservatorio Astronomico di Padova
31 IFN - CNR Institute for Photonics and Nanotechnologies
32 Department of Physics and Astronomy [Uppsala]
33 Department of Industrial Engineering [Padova]
34 OAT - INAF - Osservatorio Astronomico di Trieste
35 IAA - Instituto de Astrofísica de Andalucía
36 DLR Institut für Planetenforschung
37 Institute of Space Science [Taiwan]
38 Operations Department (ESAC)
39 OAR - INAF - Osservatorio Astronomico di Roma
40 DEI - Department of Information Engineering [Padova]
41 SwRI Planetary Science Directorate [Boulder]
42 CBK - Space Research Centre of Polish Academy of Sciences
43 ISSI - International Space Science Institute [Bern]
44 Department of Space Studies [Boulder]
45 APL - Johns Hopkins University Applied Physics Laboratory [Laurel, MD]
46 PSI - Planetary Science Institute [Tucson]
47 LMD - Laboratoire de Météorologie Dynamique (UMR 8539)

On 19 Feb. 2016 nine Rosetta instruments serendipitously observed an outburst of gas and dust from the nucleus of comet 67P/Churyumov-Gerasimenko. Among these instruments were cameras and spectrometers ranging from UV over visible to microwave wavelengths, in-situ gas, dust and plasma instruments, and one dust collector. At 9:40 a dust cloud developed at the edge of an image in the shadowed region of the nucleus. Over the next two hours the instruments recorded a signature of the outburst that significantly exceeded the background. The enhancement ranged from 50% of the neutral gas density at Rosetta to factors >100 of the brightness of the coma near the nucleus. Dust related phenomena (dust counts or brightness due to illuminated dust) showed the strongest enhancements (factors >10). However, even the electron density at Rosetta increased by a factor 3 and consequently the spacecraft potential changed from ∼−16 V to −20 V during the outburst. A clear sequence of events was observed at the distance of Rosetta (34 km from the nucleus): within 15 minutes the Star Tracker camera detected fast particles (∼25 m s⁻¹) while 100 μm radius particles were detected by the GIADA dust instrument ∼1 hour later at a speed of ~6 m s⁻¹. The slowest were individual mm to cm sized grains observed by the OSIRIS cameras. Although the outburst originated just outside the FOV of the instruments, the source region and the magnitude of the outburst could be determined.

Keywords: 67P/Churyumov-Gerasimenko; comets

Domains: Astrophysics [astro-ph]

Eberhard Grün, Jessica Agarwal, Nicolas Altobelli, Kathrin Altwegg, Mark Stephen Bentley, et al.. The 2016 Feb 19 outburst of comet 67P/CG: an ESA Rosetta multi-instrument study. Monthly Notices of the Royal Astronomical Society, 2016, 462 (Suppl. 1), pp.S220-S234. ⟨10.1093/mnras/stw2088⟩. ⟨insu-01368002⟩