Morphological Forms of Cometary Activity

Thursday, 18 December 2014
Horst Uwe Keller1, Michael F A'Hearn2, Olivier Groussin3, Stubbe Faurschou Hviid4, Ekkehard Kuhrt5, Nicolas Thomas6, Sebastien Besse7, Stefan Schroeder5 and Jean-Baptiste Vincent8, (1)Technical University of Braunschweig, Braunschweig, Germany, (2)University of Maryland, College Park, MD, United States, (3)Aix Marseille University, Marseille Cedex 03, France, (4)German Aerospace Center DLR Berlin, Berlin, Germany, (5)German Aerospace Center DLR Berlin, Institute of Planetary Research, Berlin, Germany, (6)University of Bern, Bern, Switzerland, (7)European Space Research and Technology Centre, Noordwijk, Netherlands, (8)Max-Planck Institute for Solar System Research, Germany, Goettigen, Germany
The flyby of comet 103/P Hartley 2 (A’Hearn et al. Science 332, 1396 (2011)) revealed different kinds of activity from morphologically different areas of the nucleus. The small end spewed out icy grains most probably driven by CO2. Here mounds could be seen near the limit of resolution (Thomas et al. Icarus 222, 550 (2013)). Water sublimation is enhanced over a large smooth area between the sub nuclei. Some water ice is found on the surface near the dawn terminator. First images of the nucleus of comet 67/P Churyumov-Gerasimenko show a comparable multitude of surface morphologies. We expect that we can study the various forms of activity during the approach and rendezvous.