Surface changes on comet 67P/Churyumov-Gerasimenko suggest a more active past.
The Rosetta spacecraft spent ~2 years orbiting comet 67P/Churyumov-Gerasimenko, most of it at distances that allowed surface characterization and monitoring at submeter scales. From December 2014 to June 2016, numerous localized changes were observed, which we attribute to cometary-specific weathering, erosion, and transient events driven by exposure to sunlight and other processes. While the localized changes suggest compositional or physical heterogeneity, their scale has not resulted in substantial alterations to the comet's landscape. This suggests that most of the major landforms were created early in the comet's current orbital configuration. They may even date from earlier if the comet had a larger volatile inventory, particularly of CO or CO2ices, or contained amorphous ice, which could have triggered activity at greater distances from the Sun.
Physikalisches Institut, Universität Bern, 3012 Bern, Switzerland. mohamed.el-maarry@lasp.colorado.edu.|Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80301, USA.
M Ramy
0000-0002-8262-0320
MR
El-Maarry
Aix Marseille Université, CNRS, Laboratoire d'Astrophysique de Marseille, UMR 7326, 13388 Marseille, France.
O
0000-0002-8997-3815
O
Groussin
Physikalisches Institut, Universität Bern, 3012 Bern, Switzerland.
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0000-0002-0146-0071
N
Thomas
NASA Ames Research Center, Moffett Field, CA 94035, USA.
M
0000-0002-3144-1277
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Pajola
Aix Marseille Université, CNRS, Laboratoire d'Astrophysique de Marseille, UMR 7326, 13388 Marseille, France.
A-T
0000-0003-4841-4651
AT
Auger
Jet Propulsion Laboratory, Pasadena, CA 91109, USA.
B
B
Davidsson
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
X
0000-0002-4302-5633
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Hu
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
S F
0000-0003-0623-4767
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Hviid
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
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0000-0003-1249-8582
J
Knollenberg
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
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Güttler
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
C
0000-0001-8475-9898
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Tubiana
LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France.
S
0000-0001-7678-3310
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Fornasier
LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France.
C
0000-0002-2941-3875
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Feller
LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France.
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P
Hasselmann
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
J-B
0000-0001-6575-3079
JB
Vincent
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
H
H
Sierks
Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy.
C
C
Barbieri
Laboratoire d'Astrophysique de Marseille, UMR 7326 CNRS & Université Aix-Marseille, 13388 Marseille Cedex 13, France.
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P
Lamy
Centro de Astrobiología, Instituto Nacional de Técnica Aeroespacial, 28850 Torrejón de Ardoz, Madrid, Spain.|International Space Science Institute, 3012 Bern, Switzerland.
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0000-0002-3585-380X
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Rodrigo
Operations Department, European Space Astronomy Centre/ESA, P.O. Box 78, 28691 Villanueva de la Cañada, Madrid, Spain.
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Koschny
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.|Institut für Geophysik und Extraterrestrische Physik, Technische Universität Braunschweig, 38106 Braunschweig, Germany.
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HU
Keller
Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden.|Polish Academy of Sciences, Space Research Center, 00716 Warsaw, Poland.
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H
Rickman
Department of Astronomy, University of Maryland, College Park, MD 20742, USA.
M F
0000-0002-9362-1193
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A'Hearn
LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France.
M A
0000-0002-1345-0890
MA
Barucci
Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), CNRS-Université de Versailles Saint-Quentin-en-Yvelines-Institut Pierre Simon Laplace, 78280 Guyancourt, France.
J-L
JL
Bertaux
Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy.
I
0000-0002-0616-2444
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Bertini
Operations Department, European Space Astronomy Centre/ESA, P.O. Box 78, 28691 Villanueva de la Cañada, Madrid, Spain.
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Besse
Department of Astronomy, University of Maryland, College Park, MD 20742, USA.
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0000-0002-2668-7248
D
Bodewits
Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova, 35122 Padova, Italy.
G
0000-0001-9021-1140
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Cremonese
Consiglio Nazionale delle Ricerche-Istituto di Fotonica e Nanotecnologie, Unità Organizzativa di Supporto, Padova Luxor, 35131 Padova, Italy.
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Da Deppo
Department of Industrial Engineering, University of Padova, 35131 Padova, Italy.
S
0000-0002-6757-6616
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Debei
University of Trento, 38123 Trento, Italy.
M
0000-0003-1562-0328
M
De Cecco
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
J
0000-0001-8341-007X
J
Deller
LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France.
J D P
0000-0002-5758-1286
JD
Deshapriya
INAF, Osservatorio Astronomico di Trieste, 34014 Trieste, Italy.
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0000-0001-8435-5287
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Fulle
Instituto de Astrofísica de Andalucía (CSIC), c/ Glorieta de la Astronomía s/n, 18008 Granada, Spain.
P J
0000-0002-7332-6269
PJ
Gutierrez
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
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0000-0001-8224-6845
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Hofmann
Graduate Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan.
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WH
Ip
Aix Marseille Université, CNRS, Laboratoire d'Astrophysique de Marseille, UMR 7326, 13388 Marseille, France.
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Jorda
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
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0000-0002-6431-0556
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Kovacs
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
J-R
0000-0002-1170-1721
JR
Kramm
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
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0000-0002-7845-8797
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Kührt
Operations Department, European Space Astronomy Centre/ESA, P.O. Box 78, 28691 Villanueva de la Cañada, Madrid, Spain.
M
0000-0002-5666-8582
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Küppers
Instituto de Astrofísica de Andalucía (CSIC), c/ Glorieta de la Astronomía s/n, 18008 Granada, Spain.
L M
0000-0002-7184-920X
LM
Lara
Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy.
M
0000-0001-7976-2339
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Lazzarin
Graduate Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan.
Z-Yi
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Lin
Instituto de Astrofísica de Andalucía (CSIC), c/ Glorieta de la Astronomía s/n, 18008 Granada, Spain.
J J
0000-0002-7946-2624
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Lopez Moreno
Solar System Exploration Research, Virtual Institute, Southwest Research Institute, Boulder, CO 80302, USA.
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0000-0003-2548-3291
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Marchi
Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy.
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0000-0003-0724-9987
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Marzari
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
S
0000-0002-0457-3872
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Mottola
Consiglio Nazionale delle Ricerche-Istituto di Fotonica e Nanotecnologie, Unità Organizzativa di Supporto, Padova Luxor, 35131 Padova, Italy.|Department of Information Engineering, University of Padova, 35131 Padova, Italy.|Centro di Ateneo di Studi ed Attivitá Spaziali "Giuseppe Colombo" (CISAS), University of Padova, 35131 Padova, Italy.
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0000-0003-2007-3138
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Naletto
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
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0000-0002-4909-9692
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Oklay
Physikalisches Institut, Universität Bern, 3012 Bern, Switzerland.
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A
Pommerol
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
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0000-0001-9005-4202
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Preusker
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany.
F
0000-0002-1430-9223
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Scholten
Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany.
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0000-0002-4120-7361
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Shi