Rotational Variation of Outgassing Morphology in 67P/Churyumov-Gerasimenko

Michael F. A'Hearn (1) , Dennis Bodewits (1) , Fiorangela La Forgia (2) , Luisa M. Lara (3) , Jessica Agarwal (4) , Jean-Loup Bertaux (5) , Gabriele Cremonese (6) , Björn Davidsson (7) , Sonia Fornasier (8) , Carsten Güttler (4) , Jorg Knollenberg (9) , Monica Lazzarin (2) , Cedric Leyrat (8) , Zhong-Yi Lin (10) , Sara Magrin (2) , Giampiero Naletto (11, 12) , Holger Sierks (4) , Colin Snodgrass (13) , Nicolas Thomas (14) , Cecilia Tubiana (4) , Jean-Baptiste Vincent (4)

1 Department of Astronomy [College Park]
2 Dipartimento di Fisica e Astronomia "Galileo Galilei"
3 IAA - Instituto de Astrofísica de Andalucía
4 MPS - Max-Planck-Institut für Sonnensystemforschung
5 PLANETO - LATMOS
6 OAPD - INAF - Osservatorio Astronomico di Padova
7 Department of Physics and Astronomy [Uppsala]
8 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
9 DLR Institute of Planetary Research
10 IANCU - Institute of Astronomy [Taiwan]
11 Department of Industrial Engineering [Padova]
12 CISAS - Centro di Ateneo di Studi e Attività Spaziali “Giuseppe Colombo”
13 OU - The Open University [Milton Keynes]
14 UNIBE - Universität Bern [Bern]

Images of the innermost coma of comet 67P/Churyumov-Gerasimenko taken in various gaseous species with the OSIRIS camera on Rosetta show localized sources that expand hemispherically, contrary to the narrow jets seen in broad band images, which are domnated by continuum radiation reflected by the grains. The gaseous images have the continuum removed, but we have not derived column densities because of uncertainty about physical processes. Thus the morphology is the most reliable aspect of the data. We will compare the morphology in various species and attempt to estimate the decoupling distance of the grains from the gas. We will also attempt to relate these features to the point of origin on the nucleus.

Domains: Earth and Planetary Astrophysics [astro-ph.EP]

Michael F. A'Hearn, Dennis Bodewits, Fiorangela La Forgia, Luisa M. Lara, Jessica Agarwal, et al.. Rotational Variation of Outgassing Morphology in 67P/Churyumov-Gerasimenko. IAU General Assembly, Aug 2015, Honolulu, United States. pp.2257858. ⟨insu-01191779⟩