@article{edbf32afc47d43cab6fae76bd2a1faaf,
title = "Observations of Comet 9P/Tempel 1 around the Deep Impact event by the OSIRIS cameras onboard Rosetta",
abstract = "The OSIRIS cameras on the Rosetta spacecraft observed Comet 9P/Tempel 1 from 5 days before to 10 days after it was hit by the Deep Impact projectile. The Narrow Angle Camera (NAC) monitored the cometary dust in 5 different filters. The Wide Angle Camera (WAC) observed through filters sensitive to emissions from OH, CN, Na, and OI together with the associated continuum. Before and after the impact the comet showed regular variations in intensity. The period of the brightness changes is consistent with the rotation period of Tempel 1. The overall brightness of Tempel 1 decreased by about 10% during the OSIRIS observations. The analysis of the impact ejecta shows that no new permanent coma structures were created by the impact. Most of the material moved with ∼ 200 m s-1. Much of it left the comet in the form of icy grains which sublimated and fragmented within the first hour after the impact. The light curve of the comet after the impact and the amount of material leaving the comet (4.5 - 9 × 106 kg of water ice and a presumably larger amount of dust) suggest that the impact ejecta were quickly accelerated by collisions with gas molecules. Therefore, the motion of the bulk of the ejecta cannot be described by ballistic trajectories, and the validity of determinations of the density and tensile strength of the nucleus of Tempel 1 with models using ballistic ejection of particles is uncertain.",
keywords = "Comet Tempel-1, Comets, Impact processes, coma",
author = "Keller, {Horst Uwe} and Michael K{\"u}ppers and Sonia Fornasier and Guti{\'e}rrez, {Pedro J.} and Hviid, {Stubbe F.} and Laurent Jorda and J{\"o}rg Knollenberg and Lowry, {Stephen C.} and Miriam Rengel and Ivano Bertini and Gabriele Cremonese and Ip, {Wing H.} and Detlef Koschny and Rainer Kramm and Ekkehard K{\"u}hrt and Lara, {Luisa Maria} and Holger Sierks and Nicolas Thomas and Cesare Barbieri and Philippe Lamy and Hans Rickman and Rafael Rodrigo and A'Hearn, {Michael F.} and Francesco Angrilli and Barucci, {Maria Antonella} and Bertaux, {Jean Loup} and {da Deppo}, Vania and Davidsson, {Bj{\"o}rn J.R.} and {de Cecco}, Mariolino and Stefano Debei and Marco Fulle and Fritz Gliem and Olivier Groussin and {Lopez Moreno}, {Jos{\'e} J.} and Francesco Marzari and Giampiero Naletto and Lola Sabau and {Sanz Andr{\'e}s}, Angel and Wenzel, {Klaus Peter}",
note = "Funding Information: The OSIRIS imaging system on board Rosetta is managed by the Max-Planck-Institute for Solar System Research in Katlenburg-Lindau (Germany), thanks to an International collaboration between Germany, France, Italy, Spain, and Sweden. We acknowledge the work of the Rosetta Science Operations Centre at ESA/ESTEC and the Rosetta Mission Operations Centre at ESA/ESOC in coordinating the observation timelines and operating the spacecraft, in particular K. Wirth, V. Dhiri, P. Ferri, E. Montagnon, A. Hubault, J. Morales, V. Companys, and M. Lauer. We acknowledge the funding of the national space agencies ASI, CNES, DLR, the Spanish Space Program (Ministerio de Educacion y Ciencia), SNSB and ESA. IRAF is distributed by the National Optical Astronomy Observatories, which is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under cooperative agreement with the National Science Foundation. We acknowledge JPL's Horizons online ephemeris generator for providing the comet's position and rate of motion during the observations. This research has made use of NASA's Astrophysics Data System.",
year = "2007",
month = mar,
doi = "10.1016/j.icarus.2006.09.023",
language = "???core.languages.en_GB???",
volume = "187",
pages = "87--103",
journal = "Icarus",
issn = "0019-1035",
number = "1",
}