A mini outburst from the nightside of comet 67P/Churyumov-Gerasimenko observed by the OSIRIS camera on Rosetta

Please use this identifier to cite or link to this item: https://ir.lib.ncu.edu.tw/handle/987654321/102062

Title:	A mini outburst from the nightside of comet 67P/Churyumov-Gerasimenko observed by the OSIRIS camera on Rosetta
Authors:	葉永烜;Knollenberg, J.;Lin, Z. Y.;Hviid, S. F.;Oklay, N.;Vincent, J.-B.;Bodewits, D.;Mottola, S.;Pajola, M.;Sierks, H.;Barbieri, C.;Lamy, P.;Rodrigo, R.;Koschny, D.;Rickman, H.;A’Hearn, M. F.;Barucci, M. A.;Bertaux, J. L.;Bertini, I.;Cremonese, G.;Davidsson, B.;Da Deppo, V.;Debei, S.;De Cecco, M.;Fornasier, S.;Fulle, M.;Groussin, O.;Gutiérrez, P. J.;Ip, W.-H.;Jorda, L.;Keller, H. U.;Kührt, E.;Kramm, J. R.;Küppers, M.;Lara, L. M.;Lazzarin, M.;Lopez Moreno, J. J.;Marzari, F.;Naletto, G.;Thomas, N.;Güttler, C.;Preusker, F.;Scholten, F.;Tubiana, C.
Contributors:	理學院天文研究所
Keywords:	Astrophysics;Cameras;Comets;comets: general;comets: individual: 67P/Churyumov-Gerasimenko;Dust;Earth and Planetary Astrophysics;Ejection;methods: numerical;Onboard;Outbursts;Radiance;Sciences of the Universe
Date:	2016-12-01
Issue Date:	2026-04-21 14:58:46 (UTC+8)
Publisher:	EDP Sciences
Abstract:	摘要： Context. On 12 March 2015 the OSIRIS WAC camera onboard the ESA Rosetta spacecraft orbiting comet 67P/Churyumov-Gerasimenko observed a small outburst originating from the Imhotep region at the foot of the big lobe of the comet. These measurements are unique since it was the first time that the initial phase of a transient outburst event could be directly observed. Aims. We investigate the evolution of the dust jet in order to derive clues about the outburst source mechanism and the ejected dust particles, in particular the dust mass, dust-to-gas ratio and the particle size distribution. Methods. Analysis of the images and of the observation geometry using comet shape models in combination with gasdynamic modeling of the transient dust jet were the main tools used in this study. Synthetic images were computed for comparison with the observations. Results. Analysis of the geometry revealed that the source region was not illuminated until 1.5 h after the event implying true nightside activity was observed. The outburst lasted for less than one hour and the average dust production rate during the initial four minutes was of the order of 1 kg/s. During this time the outburst dust production rate was approximately constant, no sign for an initial explosion could be detected. For dust grains between 0.01−1 mm a power law size distribution characterized by an index of about 2.6 provides the best fit to the observed radiance profiles. The dust-to-gas ratio of the outburst jet is in the range 0.6−1.8. 出版者： EDP Sciences 出版日期： 2016-12-01 出處： Astronomy and astrophysics (Berlin), 2016-12, Vol.596, p.A89 資源來源： EDP Sciences 版權： licence_http://creativecommons.org/publicdomain/zero 識別號： ISSN: 0004-6361 識別號： ISSN: 1432-0746 識別號： EISSN: 1432-0746 識別號： DOI: 10.1051/0004-6361/201527744
Appears in Collections:	[Graduate Institute of Astronomy] journal & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	33	View/Open

社群 sharing

Loading...