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Your search keyword '"Hviid, Stubbe F."' showing total 4 results
Start Over Author "Hviid, Stubbe F." Topic osiris
4 results on '"Hviid, Stubbe F."'

1. Boulders on Lutetia

Author

Küppers, Michael, Moissl, Richard, Vincent, Jean-Baptiste, Besse, Sébastien, Hviid, Stubbe F., Carry, Benoît, Grieger, Björn, Sierks, Holger, Keller, Horst Uwe, Marchi, A’Hearn, Simone (M., Angrilli, F., Barbieri, C., Barucci, A., Bertaux, J. -L., Cremonese, G., Da Deppo, V., Davidsson, B., Debei, S., De Cecco, M., Fornasier, S., Fulle, M., Groussin, O., Gutierrez, P., W. -H., Ip, Jorda, L., Koschny, D., Knollenberg, J., Kramm, J. R., Kuhrt, E., Lamy, P., Lara, L. M., Lazzarin, M., Lopez-Moreno, J. J., Marzari, F., Michalik, H., Naletto, G., Rickman, H., Rodrigo, R., Sabau, L., Thomas, N., and Wenzel), K. -P.

Subjects
biology, Astronomy and Astrophysics, biology.organism_classification, Lutetia, Astrobiology, Imaging, Boulders, Cratering, Space and Planetary Science, Impact crater, Asteroid, Osiris, Ejecta, Geology
Abstract

More than 200 boulders are among the many prominent geological features seen on Lutetia by the OSIRIS cameras onboard Rosetta. Most are concentrated around the central crater in Baetica regio with a few more apparently associated with Patavium crater. The size range of boulders visible to OSIRIS is about 60–300 m. We model the trajectories of boulders ejected from the central crater and show that their distribution is consistent with most of them being created from that crater, similar to the situation on asteroid Eros where most of the boulders are believed to originate from Shoemaker crater. We evaluate various destruction mechanisms for ejecta blocks and conclude that, using current estimates of the number of small asteroids in the main belt, destruction by impacts of small (several meters diameter) projectiles limits the lifetime of the boulders (and the age of the central crater) to a maximum of 300 million years. Since several analyses of crater ages and size distributions also come up with surprisingly young ages, the size-frequency distribution of small main-belt asteroids (below the size currently reached by surveys) may warrant to be revisited.

Published
2012

2. The Light Curve Of The Dust Cloud Ejected By The Collision Between The Deep Impact Projectile And The Nucleus Of Comet 9P/Tempel 1

Author

Küppers, Michael, Rengel, Miriam, Keller, H.U., Gutiérrez, Pedro J., and Hviid, Stubbe F.

Subjects
Projectile impact, Light curve, Astrophysics, Velocity distribution, Comet 9P/Tempel 1, Dust cloud, Rosetta spacecraft, Physics::Space Physics, Narrow Angle Camera (NAC), Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, OSIRIS, Deep Impact spacecraft, Astrophysics::Galaxy Astrophysics
Abstract

Contribution presented at the 39th Annual Meeting of the Division for Planetary Sciences of the American Astronomical Association (DPS 2007), October 7-12, 2007 Orlando, Florida., When Deep Impact fired its projectile into the nucleus of comet 9P/Tempel 1, a cloud made of dust and icy grains was ejected from the impact crater. The dust was subsequently accelerated by gas drag. About a week after the impact event, the dust cloud has dispersed due to its expansion and the force exerted by solar radiation pressure. The light curve of the dust cloud contains information about its formation and evolution: the time scale of the production of impact created material can be derived from the time scale of the brightness increase. The velocity distribution of the cloud is indicative of acceleration processes in the inner coma of the comet. Finally, the abundance of large dust particles created by the impact can be estimated from the brightness of the cloud several days after the impact when small particles have been pushed away by radiation pressure., Here we analyze data obtained by the Narrow Angle Camera (NAC) of OSIRIS onboard the ESA spacecraft Rosetta to derive the velocity distribution of the dust cloud from an inversion of its light curve. OSIRIS observed comet Tempel 1 near-continuously for more than two weeks around the impact. A model of the expansion of the ejecta is compared to the light curve seen by the NAC. We derive a broad velocity distribution of the dust particles, which peaks at around 225 m/s, in good agreement with published estimates. The velocity suggest that the impact ejecta were quickly accelerated by gas in the cometary coma. We will discuss implications of our results for the evolution of the dust cloud during the first hours after the impact and provide estimates of the released dust mass., We acknowledge the funding of the agencies ASI, CNES, DLR, the Spanish Space Program (Ministerio de Educación y Ciencia), SNSB and ESA.

Published
2007

3. Observations of Comet 9P/Tempel 1 around the Deep Impact event by the OSIRIS cameras onboard Rosetta

Author

HORST UWE KELLER, Michael, Kppers, Sonia, Fornasier, Gutierrez, PEDRO J., Hviid, STUBBE F., Laurent, Jorda, Jrg, Knollenberg, Lowry, STEPHEN C., Miriam, Rengel, Bertini, Ivano, Gabriele, Cremonese, WING H., Ip, Detlef, Koschny, Rainer, Kramm, Ekkehard, Khrt, Luisa, Maria, Lara, Holger, Sierks, Nicolas, Thomas, Barbieri, Cesare, Philippe, Lamy, Hans, Rickman, Rafael, Rodrigo, Ahearn, MICHAEL F., Francesco, Angrilli, MARIA ANTONELLA BARUCCI, Jean, Loup, Bertaux, VANIA DA DEPPO, Davidsson, BJRN J. R., MARIOLINO DE CECCO, Debei, Stefano, Marco, Fulle, Fritz, Gliem, Olivier, Groussin, LOPEZ MORENO, JOS J., Marzari, Francesco, Naletto, Giampiero, Lola, Sabau, ANGEL SANZ ANDRS, KLAUS PETER WENZEL, Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Centro di Ateneo di Studi e Attività Spaziali 'Giuseppe Colombo' (CISAS), Università degli Studi di Padova = University of Padua (Unipd), Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), DLR Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), Astrophysics Research Centre [Belfast] (ARC), Queen's University [Belfast] (QUB), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Institute of Space Science [Taiwan], National Central University [Taiwan] (NCU), European Space Research and Technology Centre (ESTEC), Agence Spatiale Européenne = European Space Agency (ESA), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Department of Astronomy and Space Physics [Uppsala], Uppsala University, Department of Astronomy [College Park], University of Maryland [College Park], University of Maryland System-University of Maryland System, Dipartimento di Ingegneria Meccanica [Padova], Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Information Engineering [Padova] (DEI), Università degli Studi di Trento (UNITN), INAF - Osservatorio Astronomico di Trieste (OAT), Institut für Datentechnik und Kommunikationsnetze, Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Dipartimento di Fisica e Astronomia 'Galileo Galilei', Instituto Nacional de Técnica Aeroespacial (INTA), Instituto de Microgravedad 'Ignacio Da Riva', and Universidad Politécnica de Madrid (UPM)

Subjects
Solar System, 010504 meteorology & atmospheric sciences, TELESCOPE, Comet, Narrow angle, coma, impact processes, surfaces, Osiris, 01 natural sciences, Aeronáutica, Comet Tempel-1, Comets, Impact processes, 0103 physical sciences, comets, RATES, Comets, coma, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Physics, COMET-9P/TEMPEL-1, biology, Spacecraft, business.industry, Astronomy, Astronomy and Astrophysics, biology.organism_classification, Light curve, Astronomía, DUST ENVIRONMENT, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, dust, ATMOSPHERES, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

17 pp.-- Final full-text version of the paper available at: http://dx.doi.org/10.1016/j.icarus.2006.09.023., 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. 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 x 10e6 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., 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 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.

Published
2007
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4. Determination Of The Light Curve Of Rosetta Target Asteroid 2867 Steins With The Osiris Narrow Angle Camera Onboard Rosetta

Author

Küppers, Michael, Keller, Horst Uwe, Hviid, Stubbe F., Mottola, Stefano, Fornasier, Sonia, Barbieri, Cesare, Barucci, Maria Antonella, Gutiérrez, P., Lamy, Philippe, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)

Subjects
Rosetta, Lightcurves, 2867 Steins, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Osiris, Asteroids
Abstract

International audience

Published
2006

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