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A speculation about comets and the earthAssuming that some 100 earth masses of excess icy conglomerate material accumulated in the Uranus-Neptune region, it is suggested that dispersal by perturbations could have transferred a large fraction of that material into Jupiter-crossing orbits, with a time constant for dissipation of the order of 10 to 100 million years. The possible formation of a 'cometary nebula' within Jupiter's orbit is considered along with the accumulation of a significant amount of cometary material on earth. Calculations are presented which show that the cometary flux within Jupiter may have attained a million times its present value for a period of 10 to 100 million years, that the current flux on earth adds only about one ten-millionth to one hundred-millionth of an earth mass in 4.6 billion years, and that the accretion rate scales only with the local density of the cometary material being collisionally destroyed. The possibility is discussed that the solar wind was unable to cope with the large cometary flux within Jupiter, resulting in a 'choke up' of cometary debris in the inner solar system and providing the cometary nebula with a density many orders of magnitude higher than the present value.
Document ID
19760055990
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Whipple, F. L.
(Harvard College Observatory and Smithsonian Astrophysical Observatory Cambridge, Mass., United States)
Date Acquired
August 8, 2013
Publication Date
January 1, 1976
Subject Category
Lunar And Planetary Exploration
Accession Number
76A38956
Funding Number(s)
CONTRACT_GRANT: NSG-7082
Distribution Limits
Public
Copyright
Other

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