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Comet nuclei: Morphology and implied processes of surface modification
Planetary and Space Science, 2006Abstract Surface morphology and related issues for nuclei of three comets: Halley, Borrelly and Wild 2, are considered in the paper. Joint consideration of publications and results of our analysis of the comets’ images led to conclusions, partly new, partly repeating conclusions published by other researchers.
Basilevsky, A., Keller, H.
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Temperatures within comet nuclei
Journal of Geophysical Research: Solid Earth, 1985We have performed a theoretical study of temperatures beneath the surface of a comet's nucleus. We solve the one‐dimensional heat conduction equation for the outer portion of the comet. The upper boundary condition of the model is given by energy balance at the surface of the nucleus, including conduction of heat inward, radiation, insolation as ...
S W, Squyres, C P, McKay, R T, Reynolds
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Disintegration of comet nuclei
Physics-Uspekhi, 2012The breaking up of comets into separate pieces, each with its own tail, was seen many times by astronomers of the past. The phenomenon was in sharp contrast to the idea of the eternal and unchangeable celestial firmament and was commonly believed to be an omen of impending disaster, especially for comets with tails stretching across half the sky. It is
L. Ksanfomality
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Radioactive Heating of Porous Comet Nuclei
Icarus, 1995Abstract Radioactive heating is the main energy source of comets residing in the distant parts of the Solar System. It should determine whether liquid water could have existed in comets and whether comets, presumably formed of amorphous ice, could have retained the ice, at least partly, in this pristine form.
D. Prialnik, M. Podolak
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Science, 1982
Photography of the nucleus of comet Halley is the goal of several planned space missions. The nucleus of a comet is surrounded by a cloud of dust particles. If this cloud is optically thick, it will prevent observation of the nuclear surface. Broadband photometry of nine comets has been analyzed to determine the visibility of their nuclei.
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Photography of the nucleus of comet Halley is the goal of several planned space missions. The nucleus of a comet is surrounded by a cloud of dust particles. If this cloud is optically thick, it will prevent observation of the nuclear surface. Broadband photometry of nine comets has been analyzed to determine the visibility of their nuclei.
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On the origin of internal layers in comet nuclei
Icarus, 2018Abstract We present an analysis of the layered structure on 67P/Churyumov–Gerasimenko’ s Hathor cliff and propose a mechanism (self-sustaining, dual-mode propagation of amorphous to crystalline ice phase-change fronts into the nucleus interior) for its origin. If this is a viable mechanism, the strata must be geologically young (∼106 y).
Michael J.S. Belton +3 more
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Numerical simulation of comet nuclei I. Water-ice comets
Icarus, 1985A one-dimensional numerical model of pure water-ice cometary nuclei is presented, and the influence of the nuclear interior as a heat reservoir on the behavior of the nuclear surface is examined. It is shown that a number of effects, including the thermal inertia due to heat stored in the core and the release of latent heat, which goes entirely into ...
G. Herman, M. Podolak
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Note on the structure of comet nuclei
Planetary and Space Science, 1999Abstract The recent developments in cometary studies suggest rather low mean densities and weak structures for the nuclei. They appear to be accumulations of fairly discrete units loosely bound together, as deduced from the observations of Comet Shoemaker–Levy 9 during its encounter with Jupiter. The compressive strengths deduced from comet splitting
F. Whipple
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Numerically improved thermochemical evolution models of comet nuclei
Planetary and Space Science, 1999Abstract An improved unidimensional model of the heat transport and gas diffusion within a porous cometary nucleus is presented, in which the time-dependent gas diffusion equation is coupled with the heat diffusion equation to describe the energy transport due to sublimation and recondensation of volatiles, but is solved independently using a ...
R. Orosei +7 more
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