Results 141 to 150 of about 2,512 (186)

Light scattering in cometary dust comae

Earth, Moon, and Planets, 1987
Single and multiple scattering calculations were performed for a spherically symmetric cometary atmosphere irradiated by a plane parallel source. It is suggested that the increased flux found for anisotropic phase functions is due to the effect of directional scattering in the forward sun-comet axis. The isotropic multiply scattered flux at the surface
Gary Herman, Heikki Salo
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Cometary dust coma models. II. Computer experiments

Astronomische Nachrichten, 1986
AbstractComputer simulations of a cometary dust coma are presented which take into account different distribution functions of the ejected material as well as anisotropic ejection due to the rotation of the nucleus and single active regions on its surface.
Gottlöber, S., Liebscher, D.-E., Mücket, J. P., Müller, V.   +3 more
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Cometary dust coma models. I. Analytic calculations

Astronomische Nachrichten, 1986
AbstractThe dust coma of comets is calculated within the fountain model of isotropically ejected particles. A method to estimate the particle size distribution is proposed.
Gottlöber, S., Liebscher, D.-E., Mücket, J. P., Müller, V.   +3 more
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The Dust Coma of Comet C/1999 S4 (LINEAR)

Earth, Moon, and Planets, 2002
Comet C/1999 S4 (LINEAR) showed a very special behaviour between 28 June and 1 July 2000. Optical observations of the dust coma in two distinct continuum bands revealed that it changed morphologically as well as in colour. The two-dimensional coma morphology indicates a splitting of the nucleus which probably occurred shortly before the observations of
Rita Schulz, Joachim A. Stüwe
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The dust coma of comets

2008
Analytical 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 the Sun,
K. W. Michel, T. Nishimura
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Carbonaceous matter in cometary dust and coma

Advances in Space Research, 1995
The analysis of carbonaceous matter in p/Halley's dust and coma via mass spectrometry of positive ions is reviewed. Dust impact generated ions were analyzed by the PUMA instrument aboard VEGA I, and coma plasma ions by the PICCA instrument aboard GIOTTO. For the organic molecules results an overall C:H:O:N ratio of 1.:1.4:0.6:0.1.
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The Large-Grained Dust Coma of 174P/Echeclus

Publications of the Astronomical Society of the Pacific, 2008
On 2005 December 30, Y.-J. Choi and P. R. Weissman discovered that the formerly dormant Centaur 2000 EC98 was in strong outburst. Previous observations by P. Rousselot et al. spanning a 3-year period indicated a lack of coma down to the 27 mag arcsec 2 level.We present Spitzer Space Telescope MIPS observations of this newly active Centaur--now known as
Bauer, James M., Choi, Young-Jun, Weissman, Paul R., Stansberry, John A., Fernández, Yanga R., Roe, Henry G., Buratti, Bonnie J., Sung, Hyun-Il   +7 more
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The dust grains in the coma of Comet West

Earth, Moon, and Planets, 1987
The observed variation of reddening as function of the heliocentric distance and the spatial variation of reddening within the coma of Comet West in the visual wavelength range have been considered to infer the properties of the cometary dust grains.
K. S. Krishna Swamy, G. A. Shah
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