Tensile strength of 67P/Churyumov-Gerasimenko nucleus material from overhangs

  title={Tensile strength of 67P/Churyumov-Gerasimenko nucleus material from overhangs},
  author={Nicholas Attree and O. Groussin and Laurent Jorda and D. N'ebouy and Nicolas Thomas and Yann Brouet and Ekkehard Kuhrt and Frank Preusker and Frank Scholten and J Knollenberg and Paul Hartogh and Holger Sierks and Cesare Barbieri and Philippe Lamy and R. Rodrigo and Detlef Koschny and Hans Rickman and H. Uwe Keller and Michael F. A’Hearn and A-T Auger and M. A. Barucci and J L Bertaux and Ivano Bertini and Dennis Bodewits and Steve Boudreault and Gabriele Cremonese and Vania Da Deppo and Bj{\"o}rn J R Davidsson and Stefano Debei and Mariolino De Cecco and J Deller and M. R. El-Maarry and Sonia Fornasier and Marco Fulle and Pedro J. Guti'errez and Carsten Guttler and S F Hviid and Wing-H. Ip and Gabor Kovacs and J. Rainer Kramm and M. Kuppers and Luisa Maria Lara and Monica Lazzarin and Jos{\'e} Juan Lopez Moreno and S C Lowry and Simone Marchi and Francesco Marzari and Stefano Mottola and Giampiero Naletto and N. Oklay and Maurizio Pajola and Imre P{\'e}ter T{\'o}th and Cecilia Tubiana and J.-B. Vincen and X Shi},
  journal={Astronomy and Astrophysics},
We directly measured twenty overhanging cliffs on the surface of comet 67P/Churyumov-Gerasimenko extracted from the latest shape model and estimated the minimum tensile strengths needed to support them against collapse under the comet's gravity. We find extremely low strengths of around 1 Pa or less (1 to 5 Pa, when scaled to a metre length). The presence of eroded material at the base of most overhangs, as well as the observed collapse of two features andthe implied previous collapse of… 

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