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Long-Period Comets and the Oort Cloud
Earth, Moon, and Planets, 2000Long-period (LP) comets, Halley-type (HT) comets, and even some comets of the Jupiter family, probably come from the Oort cloud, a huge reservoir of icy bodies that surrounds the solar system. Therefore, these comets become important probes to learn about the distant Oort cloud population.
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Planetary impact probabilities for long-period comets
Icarus, 1984Abstract Planetary impact probabilities for long-period (near-parabolic) comets are determined by averaging Opik's equations over inclination and perihelion distance for each planet. These averaged values compare well with the results of more elaborate Monte Carlo calculations. The impact probabilities are proportional to the square of the normalized
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Long‐period Comets and the Oort Cloud
Annals of the New York Academy of Sciences, 1997ABSTRACT: The long‐period comets pose a unique problem for the impact hazard problem. Because of their very long orbital periods and generally large distances from the Sun, they cannot be surveyed and catalogued in the same manner as the near‐Earth asteroids and short‐period comets. They appear at random, uniformly distributed on the celestial sphere.
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Icarus, 1997
Abstract Several recent studies have noted that the orbital evolution of many comets is influenced by mean-motion resonances with Jupiter. However, the distribution and relative importance of these resonances and the orbital characteristics of the comets affected have not been addressed to date.
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Abstract Several recent studies have noted that the orbital evolution of many comets is influenced by mean-motion resonances with Jupiter. However, the distribution and relative importance of these resonances and the orbital characteristics of the comets affected have not been addressed to date.
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Heliocentric Light Curves of Long-Period Comets
We investigate the heliocentric brightening behavior of long-period comets as a function of their dynamical age, parameterized by the original reciprocal semimajor axis, 1/a0. The analysis is designed to test longstanding assertions regarding cometary photometric evolution using a substantial dataset of magnitude measurements reported to the Minor ...Pedro Lacerda +6 more
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Distribution of long-period comets in perihelion distance
International Astronomical Union Colloquium, 1999AbstractDistribution of long-period comets in perihelion distance is investigated. The relationN( > q)=C qαseems to be a good approximation to the reality −N(>q)is the number of long-period comets with perihelion distance greater than the valueq( in AU). The complete group of long-period comets is characterized by the valueα =4/3, however,
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Distribution of the Aphelia of Long-Period Comets
Publications of the Astronomical Society of Japan, 1976Abstract By examining the distribution of aphelia of all the comets observed since 1800, we find that the aphelia of long-period comets show a remarkable concentration near the antapex of the solar motion. Some possible interpretations of this phenomenon are discussed in connection with the origin of long-period comets.
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The activity pattern of distant long period comets
Modern sky surveys now regularly discover comets at distances between 5 and 10 au, or even further, from the Sun. This is expected to become more common when the Vera C Rubin observatory’s Legacy Survey of Space and Time (LSST) begins in around a year. Yet the distant activity of comets is still poorly understood – at such distancesColin Snodgrass, Carrie Holt
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Cancer statistics for African American/Black People 2022
Ca-A Cancer Journal for Clinicians, 2022Angela Giaquinto +2 more
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