Results 11 to 20 of about 2,512 (186)

3.5 The Dust Coma of Comets [PDF]

International Astronomical Union Colloquium, 1976
AbstractAnalytical expressions for the dust entrainment in the limits of low and high gas production from cometary nuclei are derived. The resulting volume density is used to evaluate the dust production of Comets Encke and Kohoutek from IR-measurements. It is predicted, that the dust in solar direction was diffuse for Comet Kohoutek during approach to
K.W. Michel, T. Nishimura
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Models of Rosetta/OSIRIS 67P Dust Coma Phase Function [PDF]

The Astronomical Journal, 2018
Abstract The phase function of the dust coma of comet 67P has been determined from Rosetta/OSIRIS images. This function shows a deep minimum at phase angles near 100°, and a strong backscattering enhancement. These two properties cannot be reproduced by regular models of cometary dust, most of them based on wavelength-sized and randomly ...
F. Moreno, D. Guirado, O. Muñoz, I. Bertini, C. Tubiana, C. Güttler, M. Fulle, A. Rotundi, V. Della Corte, S. L. Ivanovski, G. Rinaldi, D. Bockelée-Morvan, V. V. Zakharov, J. Agarwal, S. Mottola, I. Toth, E. Frattin, L. M. Lara, P. J. Gutiérrez, Z. Y. Lin, L. Kolokolova, H. Sierks, G. Naletto, P. L. Lamy, R. Rodrigo, D. Koschny, B. Davidsson, M. A. Barucci, J.-L. Bertaux, D. Bodewits, G. Cremonese, V. Da Deppo, S. Debei, M. De Cecco, J. Deller, S. Fornasier, W.-H. Ip, H. U. Keller, M. Lazzarin, J. J. López-Moreno, F. Marzari, X. Shi   +41 more
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The Dust in the Coma of Comet Halley [PDF]

International Astronomical Union Colloquium, 1991
Abstract The interstellar dust model of comets is numerically worked out to satisfy several basic constraints provided by observations of comet Halley and to derive the porosity of coma dust. The observational constraints are: (1) the strengths of the 3.4 μm and 9.7 μm emission bands; (2) the relative amount of silicates to organic materials; (3 ...
Joniek I. Hage, J. Mayo Greenberg
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Dust colors, dust release rates, and dust-to-gas ratios in the comae of six comets [PDF]

Astronomy and Astrophysics Supplement Series, 1996
In an attempt to find correlations between properties of comets, we determine the dust colors, dust release rates, and dust-to-gas mass ratios in the comae of Comets Bowell (1980 b = 1982 I), Bradfield (1979 l = 1979 X), Brorsen-Metcalf (1989 o = 1989 X), Giacobini-Zinner (1984 e = 1985 XIII), Levy (1990 c = 1990 XX), and Stephan-Oterma (1980 g = 1980 ...
G. C. Sanzovo, P. D. Singh, W. F. Huebner   +2 more
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Parameters of dust jets in comet Encke’s coma

Monthly Notices of the Royal Astronomical Society, 2020
ABSTRACTUsing 4412 positional observations, we compute eight single apparition orbits in the period 1993–2017. The analysis of the residuals of the orbit’s fit shows their systematic deviations around perihelia. We assume that these deviations in positional observations are a result of the dust emissions from a restricted area of the nucleus, and that ...
Yu Medvedev, Yu Chernetenko
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Physics of intact capture of cometary coma dust samples [PDF]

AIP Conference Proceedings, 2012
The physics of hypervelocity impact into foams are of interest because of application to comet dust capture during flyby encounters. Particles much larger than the foam cells behave as if the foam were a continuum, so that standard equations of fluid mechanics describe the effects of drag and ablation.
Anderson, W. W., Ahrens, Thomas
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Dust in cometary comae: Present understanding of the structure and composition of dust particles [PDF]

Planetary and Space Science, 2008
In situ probing of a very few cometary comae has shown that dust particles present a low albedo and a low density, and that they consist of both rocky material and refractory organics. Remote observations of solar light scattered by cometary dust provide information on the properties of dust particles in the coma of a larger set of comets.
Levasseur-Regourd, Anny Chantal, Zolensky, M., Lasue, Jérémie   +2 more
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SPECIFIC FEATURES OF STRUCTURES IN THE INNER COMA OF COMET C/2017 T2 (PANSTARRS) AS OBSERVED WITH THE OMT-800 TELESCOPE OF THE ODESSA OBSERVATORY TELESCOPE NETWORK

Odessa Astronomical Publications, 2020
Observations of the comet were carried out using the OMT-800 telescope (the primary mirror diameter D = 80 cm; the focal length F = 214 cm) of the Odessa Observatory telescope network from January to June 2020.
V. V. Kleshchenok, S. G. Kashuba, S. M. Andrievsky, Yu. M. Gorbanev   +3 more
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A numerical model of cometary dust coma structures [PDF]

Astronomy and Astrophysics, 2010
Aims. The purpose of this study is to test our numerical model of cometary dust coma structures and to use the results to infer information about the nucleus surface activity of comet 9P/Tempel 1. Methods. Parameters on the activity were first estimated from simulations of ground-based observation acquired during the preperihelion period (January to ...
Vincent, J., Böhnhardt, H., Lara, L.
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Six Outbursts of Comet 46P/Wirtanen

The Planetary Science Journal, 2021
Cometary activity is a manifestation of sublimation-driven processes at the surface of nuclei. However, cometary outbursts may arise from other processes that are not necessarily driven by volatiles.
Michael S. P. Kelley, Tony L. Farnham, Jian-Yang Li, Dennis Bodewits, Colin Snodgrass, Johannes Allen, —, Eric C. Bellm, Michael W. Coughlin, Andrew J. Drake, Dmitry A. Duev, Matthew J. Graham, Thomas Kupfer, Frank J. Masci, Dan Reiley, Richard Walters, Zwicky Transient Facility Collaboration, M. Dominik, U. G. Jørgensen, A. E. Andrews, N. Bach-Møller, V. Bozza, M. J. Burgdorf, J. Campbell-White, S. Dib, Y. I. Fujii, T. C. Hinse, M. Hundertmark, E. Khalouei, P. Longa-Peña, M. Rabus, S. Rahvar, S. Sajadian, J. Skottfelt, J. Southworth, J. Tregloan-Reed, E. Unda-Sanzana, MiNDSTEp Collaboration   +37 more
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