| Literature DB >> 25613898 |
Alessandra Rotundi1, Holger Sierks2, Vincenzo Della Corte3, Marco Fulle4, Pedro J Gutierrez5, Luisa Lara5, Cesare Barbieri6, Philippe L Lamy7, Rafael Rodrigo8, Detlef Koschny9, Hans Rickman10, Horst Uwe Keller11, José J López-Moreno5, Mario Accolla12, Jessica Agarwal2, Michael F A'Hearn13, Nicolas Altobelli14, Francesco Angrilli15, M Antonietta Barucci16, Jean-Loup Bertaux17, Ivano Bertini18, Dennis Bodewits13, Ezio Bussoletti19, Luigi Colangeli20, Massimo Cosi21, Gabriele Cremonese22, Jean-Francois Crifo17, Vania Da Deppo23, Björn Davidsson24, Stefano Debei15, Mariolino De Cecco25, Francesca Esposito26, Marco Ferrari12, Sonia Fornasier16, Frank Giovane27, Bo Gustafson28, Simon F Green29, Olivier Groussin7, Eberhard Grün30, Carsten Güttler2, Miguel L Herranz5, Stubbe F Hviid31, Wing Ip32, Stavro Ivanovski3, José M Jerónimo5, Laurent Jorda7, Joerg Knollenberg31, Rainer Kramm2, Ekkehard Kührt31, Michael Küppers14, Monica Lazzarin6, Mark R Leese29, Antonio C López-Jiménez5, Francesca Lucarelli19, Stephen C Lowry33, Francesco Marzari34, Elena Mazzotta Epifani26, J Anthony M McDonnell35, Vito Mennella26, Harald Michalik36, Antonio Molina37, Rafael Morales5, Fernando Moreno5, Stefano Mottola31, Giampiero Naletto38, Nilda Oklay2, José L Ortiz5, Ernesto Palomba3, Pasquale Palumbo12, Jean-Marie Perrin39, Julio Rodríguez5, Lola Sabau40, Colin Snodgrass41, Roberto Sordini3, Nicolas Thomas42, Cecilia Tubiana2, Jean-Baptiste Vincent2, Paul Weissman43, Klaus-Peter Wenzel9, Vladimir Zakharov16, John C Zarnecki44.
Abstract
Critical measurements for understanding accretion and the dust/gas ratio in the solar nebula, where planets were forming 4.5 billion years ago, are being obtained by the GIADA (Grain Impact Analyser and Dust Accumulator) experiment on the European Space Agency's Rosetta spacecraft orbiting comet 67P/Churyumov-Gerasimenko. Between 3.6 and 3.4 astronomical units inbound, GIADA and OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) detected 35 outflowing grains of mass 10(-10) to 10(-7) kilograms, and 48 grains of mass 10(-5) to 10(-2) kilograms, respectively. Combined with gas data from the MIRO (Microwave Instrument for the Rosetta Orbiter) and ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) instruments, we find a dust/gas mass ratio of 4 ± 2 averaged over the sunlit nucleus surface. A cloud of larger grains also encircles the nucleus in bound orbits from the previous perihelion. The largest orbiting clumps are meter-sized, confirming the dust/gas ratio of 3 inferred at perihelion from models of dust comae and trails.Entities:
Year: 2015 PMID： 25613898 DOI： 10.1126/science.aaa3905
Source DB: PubMed Journal: Science ISSN： 0036-8075 Impact factor: 47.728