The morphological diversity of comet 67P/Churyumov-Gerasimenko

Science

Volumn 347, Issue 6220, 2015, Pages

  Thomas, Nicolas ^a   Sierks, Holger ^b   Barbieri, Cesare ^c   Lamy, Philippe L ^d   Rodrigo, Rafael ^e,f   Rickman, Hans ^g,h   Koschny, Detlef ⁱ   Keller, Horst Uwe ^j,s   Agarwal, Jessica ^b   A'Hearn, Michael F ^k   Angrilli, Francesco ^c   Auger, Anne Therese ^d   Barucci, M Antonella ^l   Bertaux, Jean Loup ^m   Bertini, Ivano ^c   Besse, Sebastien ⁱ   Bodewits, Dennis ^k   Cremonese, Gabriele ⁿ   Da Deppo, Vania ^o   Davidssonn, Bjö ^g   De Cecco, Mariolino ^p   Debei, Stefano ^c   El Maarry, Mohamed Ramy ^a   Ferri, Francesca ^d   Fornasier, Sonia ^l   Fulle, Marco ^q   Giacomini, Lorenza ^c   Groussin, Olivier ^d   Gutierrez, Pedro J ^r   Güttler, Carsten ^b   Hviid, Stubbe F ^b,s   Ip, Wing Huen ^t   Jorda, Laurent ^d   Knollenberg, Jörg ^s   Kramm, J Rainer ^b   Kührt, Ekkehard ^s   Küppers, Michael ^u   La Forgia, Fiorangela ^c   Lara, Luisa M ^r   Lazzarin, Monica ^c   Lopez Moreno, Josè J ^r   Magrin, Sara ^c   Marchi, Simone ^v   Marzari, Francesco ^c   Massironi, Matteo ^c   Michalik, Harald ^j   Moissl, Richard ^u   Mottola, Stefano ^s   Naletto, Giampiero ^c,o   Oklay, Nilda ^b   Pajola, Maurizio ^c   Pommerol, Antoine ^a   Preusker, Frank ^s   Sabau, Lola ^w   Scholten, Frank ^s   Snodgrass, Colin ^b,x   Tubiana, Cecilia ^b   Vincent, Jean Baptiste ^b   Wenzel, Klaus Peter ⁱ   more..

^a UNIVERSITY OF BERN   (Switzerland)

^b MAX PLANCK INSTITUT FÜR SONNENSYSTEMFORSCHUNG   (Germany)

^c UNIVERSITY OF PADOVA   (Italy)

^d AIX MARSEILLE UNIVERSITÉ   (France)

^e INTERNATIONAL SPACE SCIENCE INSTITUTE   (Switzerland)

^f CSIC   (Spain)

^g UPPSALA UNIVERSITY   (Sweden)

^h Borowiec Astrogeodynamic Observatory   (Poland)

ⁱ EUROPEAN SPACE AGENCY   (Netherlands)

^j TECHNICAL UNIVERSITY OF BRAUNSCHWEIG   (Germany)

^k University of Maryland   (United States)

^l UNIVERSITÉ PARIS DIDEROT   (France)

^m CNRS   (France)

ⁿ INAF OSSERVATORIO ASTRONOMICO DI PADOVA   (Italy)

^o CNR   (Italy)

^p UNIVERSITY OF TRENTO   (Italy)

^q INAF OSSERVATORIO ASTRONOMICO DI TRIESTE   (Italy)

^r INSTITUTO DE ASTROFÍSICA DE ANDALUCÍA CSIC   (Spain)

^s GERMAN AEROSPACE CENTER DLR   (Germany)

^t NATIONAL CENTRAL UNIVERSITY   (Taiwan)

^u EUROPEAN SPACE AGENCY   (Spain)

^v SOUTHWEST RESEARCH INSTITUTE   (United States)

^w INSTITUTO NACIONAL DE TÉCNICA AEROESPACIAL   (Spain)

^x OPEN UNIVERSITY   (United Kingdom)

more..

Author keywords

[No Author keywords available]

Indexed keywords

COMET; EXTRATERRESTRIAL MATTER;

ARTICLE; ASTRONOMY; COMET 67P CHURYUMOV GERASIMENKO; COMET ASSAY; EVOLUTION; FLUIDIZATION; IMAGING SYSTEM; METEOROLOGICAL PHENOMENA; PRIORITY JOURNAL; SPACE FLIGHT; STRUCTURE ANALYSIS; SURFACE PROPERTY;

EID: 84921794720     PISSN: 00368075     EISSN: 10959203     Source Type: Journal    
DOI: 10.1126/science.aaa0440     Document Type: Article

References (36)

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9. A shape model using stereophotoclinometry (SPC) has also been generated. The SPC and SPG techniques are complementary, and detailed comparisons, outside the scope of this report, will be made at a later date. The exclusive use of SPG here is solely for internal consistency and simplicity and should not be interpreted as a choice of one approach over the other.
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17. Dust forms a thin veneer over the brittle material in the Ma'at and Ash regions. We here avoid the use of the word "mantle"because of the strong geological connotations and the implications of a compositionally different surface layer for which we have no evidence at this time. As noted in the text, layering is evident at several scales, but the origin (primordial or evolutionary) remains open.
18. We use the term "brittle material" to imply a rock that breaks/fractures with a high ratio of fine to coarse fragments. It is a weakly consolidated material that displays fracturing but more readily crumbles and creates debris deposits. Fractures contained in more-consolidated material (e.g., in the Aker region) show no evidence of fine fragments.
19. 2/h, where ρ is the density, g is the gravitational acceleration at the overhang, α is the angle between gravitational acceleration and the normal of the overhang, l is the length of the overhang, and h is its height. For larger, already collapsed, overhangs of ∼200 m in length (e.g., at the Ash-Imhotep interface), we estimate values of σ & le; 200 Pa. Smaller (∼10 m) overhangs are seen (with talus below in some cases where previous collapse has occurred), which suggest that collapse occurs at 10 to 20 Pa.
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