Seasonal variations in source regions of the dust jets on comet 67P/Churyumov-Gerasimenko

¹ Graduate Institute of Space Sciences, National Central University, Taoyuan City 32001, Taiwan
e-mail: ianlai@g.ncu.edu.tw
² Institute of Astronomy, National Central University, Taoyuan City 32001, Taiwan
³ Space Science Institute, Macau University of Science and Technology, Macau, PR China
⁴ Department of Earth Science, National Central University, Taoyuan City 32001, Taiwan
⁵ German Aerospace Center (DLR), Institute of Planetary Research, Rutherfordstraeβ 2, 12489 Berlin, Germany
⁶ Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg, 3 37077 Göttingen, Germany
⁷ Department of Physics and Astronomy, University of Padova, Vicolo dell’Osservatorio 3, 35122 Padova, Italy
⁸ LAM (Laboratoire d’Astrophysique de Marseille), CNRS, Aix Marseille Université, UMR 7326, 38 rue Frédéric Joliot-Curie, 13388 Marseille, France
⁹ Centro de Astrobiologia, CSIC-INTA, 28850 Torrejon de Ardoz, Madrid, Spain
¹⁰ International Space Science Institute, Hallerstraβe 6, 3012 Bern, Switzerland
¹¹ Scientific Support Office, European Space Research and Technology Centre/ESA, Keplerlaan 1, Postbus 299, 2201 AZ Noordwijk ZH, The Netherlands
¹² Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
¹³ PAS Space Research Center, Bartycka 18A, 00716 Warszawa, Poland
¹⁴ Institut für Geophysik und extraterrestrische Physik (IGEP), Technische Universität Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany
¹⁵ LESIA-Observatoire de Paris, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, 5 place J. Janssen, 92195 Meudon, France
¹⁶ CNR-IFN UOS Padova LUXOR, Via Trasea, 7, 35131 Padova, Italy
¹⁷ Center of Studies and Activities for Space G. Colombo, CISAS, “G. Colombo”, University of Padova, Padova, Italy
¹⁸ INAF, Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy
¹⁹ Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
²⁰ Department of Industrial Engineering, University of Padova, Via Venezia 1, 35131 Padova, Italy
²¹ University of Trento, Via Mesiano 77, 38100 Trento, Italy
²² INAF – Osservatorio Astronomico, Via Tiepolo 11, 34014 Trieste, Italy
²³ Instituto de Astrofísica de Andalucía (CSIC), Glorieta de la Astronomìa, 18008 Granada, Spain
²⁴ Operations Department, European Space Astronomy Centre/ESA, PO Box 78, 28691 Villanueva de la Canada, Madrid, Spain
²⁵ Department of Information Engineering, University of Padova, Via Gradenigo 6/B, 35131 Padova, Italy
²⁶ Physikalisches Institut der Universität Bern, Sidlerstr. 5, 3012 Bern, Switzerland
²⁷ Department of Physics, Auburn University, Auburn, AL 36849, USA

Received: 12 October 2017
Accepted: 5 October 2018

Abstract

Aims. We investigate the surface distribution of the source regions of dust jets on comet 67P/Churyumov-Gerasimenko as a function of time.

Methods. The dust jet source regions were traced by the comprehensive imaging data set provided by the OSIRIS scientific camera.

Results. We show in detail how the projected footpoints of the dust jets and hence the outgassing zone would move in consonance with the sunlit belt. Furthermore, a number of source regions characterized by repeated jet activity might be the result of local topographical variations or compositional heterogeneities.

Conclusions. The spatial and temporal variations in source regions of the dust jets are influenced significantly by the seasonal effect. The strong dependence on the solar zenith angle and local time could be related to the gas sublimation process driven by solar insolation on a surface layer of low thermal inertia.