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Published on: July 1, 2019
COMETARY SCIENCE. The landing(s) of Philae and inferences about comet surface mechanical properties
Jens Biele1, Stephan Ulamec1, Michael Maibaum1
1Deutsches Zentrum für Luft- und Raumfahrt (DLR)/Raumflugbetrieb und Astronautentraining, Microgravity User Support Center (MUSC), Linder Höhe 1, 51147 Cologne, Germany.
Abstract:
The Philae lander, part of the Rosetta mission to investigate comet 67P/Churyumov-Gerasimenko, was delivered to the cometary surface in November 2014. Here we report the precise circumstances of the multiple landings of Philae, including the bouncing trajectory and rebound parameters, based on engineering data in conjunction with operational instrument data. These data also provide information on the mechanical properties (strength and layering) of the comet surface. The first touchdown site, Agilkia, appears to have a granular soft surface (with a compressive strength of 1 kilopascal) at least ~20 cm thick, possibly on top of a more rigid layer. The final landing site, Abydos, has a hard surface.
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