The cometary breakup hypothesis re-examined
The theory that a Chiron-like progenitor of both Comet Encke and the Tunguska cosmic body may have fragmented beginning around 22 000 years <scp>BP</scp> and that debris from this breakup was responsible for producing the high heavy metal concentrations observed in the Late Wisconsin sta...
Published in: | Monthly Notices of the Royal Astronomical Society |
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Oxford University Press
1987
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fthighwire:oai:open-archive.highwire.org:mnras:224/4/945 2023-05-15T13:55:45+02:00 The cometary breakup hypothesis re-examined La Violette, Paul. A. 1987-02-01 00:00:00.0 text/html http://mnras.oxfordjournals.org/cgi/content/short/224/4/945 https://doi.org/10.1093/mnras/224.4.945 en eng Oxford University Press http://mnras.oxfordjournals.org/cgi/content/short/224/4/945 http://dx.doi.org/10.1093/mnras/224.4.945 Copyright (C) 1987, Oxford University Press Articles TEXT 1987 fthighwire https://doi.org/10.1093/mnras/224.4.945 2016-11-16T17:45:41Z The theory that a Chiron-like progenitor of both Comet Encke and the Tunguska cosmic body may have fragmented beginning around 22 000 years <scp>BP</scp> and that debris from this breakup was responsible for producing the high heavy metal concentrations observed in the Late Wisconsin stage polar ice is shown to be incorrectly founded. This paper re-examines the geochemical comparison which Clube & Napier make between the composition of the Tunguska cosmic body and elemental abundances previously reported for a sample of Sn-rich dust retrieved from the Wisconsin section of the Camp Century ice core. No evidence is found that would link these two sources to a common origin. Thus the hypothesis that a cometary breakup was responsible for modulating the Earth's climate and perpetuating the last ice age is unfounded. On the other hand, evidence is presented indicating that debris from the Tunguska explosion may be present in a firn layer at Dome C, East Antarctica. Analysis of the geochemical data for this stratum leads to an estimate of <f>${10}^{6}-{10}^{7}$</f> t for the mass of the Tunguska body, in approximate agreement with previous determinations. Text Antarc* Antarctica East Antarctica ice core HighWire Press (Stanford University) East Antarctica Napier ENVELOPE(-58.440,-58.440,-62.167,-62.167) Tunguska ENVELOPE(144.784,144.784,59.388,59.388) Monthly Notices of the Royal Astronomical Society 224 4 945 951 |
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HighWire Press (Stanford University) |
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English |
topic |
Articles |
spellingShingle |
Articles La Violette, Paul. A. The cometary breakup hypothesis re-examined |
topic_facet |
Articles |
description |
The theory that a Chiron-like progenitor of both Comet Encke and the Tunguska cosmic body may have fragmented beginning around 22 000 years <scp>BP</scp> and that debris from this breakup was responsible for producing the high heavy metal concentrations observed in the Late Wisconsin stage polar ice is shown to be incorrectly founded. This paper re-examines the geochemical comparison which Clube & Napier make between the composition of the Tunguska cosmic body and elemental abundances previously reported for a sample of Sn-rich dust retrieved from the Wisconsin section of the Camp Century ice core. No evidence is found that would link these two sources to a common origin. Thus the hypothesis that a cometary breakup was responsible for modulating the Earth's climate and perpetuating the last ice age is unfounded. On the other hand, evidence is presented indicating that debris from the Tunguska explosion may be present in a firn layer at Dome C, East Antarctica. Analysis of the geochemical data for this stratum leads to an estimate of <f>${10}^{6}-{10}^{7}$</f> t for the mass of the Tunguska body, in approximate agreement with previous determinations. |
format |
Text |
author |
La Violette, Paul. A. |
author_facet |
La Violette, Paul. A. |
author_sort |
La Violette, Paul. A. |
title |
The cometary breakup hypothesis re-examined |
title_short |
The cometary breakup hypothesis re-examined |
title_full |
The cometary breakup hypothesis re-examined |
title_fullStr |
The cometary breakup hypothesis re-examined |
title_full_unstemmed |
The cometary breakup hypothesis re-examined |
title_sort |
cometary breakup hypothesis re-examined |
publisher |
Oxford University Press |
publishDate |
1987 |
url |
http://mnras.oxfordjournals.org/cgi/content/short/224/4/945 https://doi.org/10.1093/mnras/224.4.945 |
long_lat |
ENVELOPE(-58.440,-58.440,-62.167,-62.167) ENVELOPE(144.784,144.784,59.388,59.388) |
geographic |
East Antarctica Napier Tunguska |
geographic_facet |
East Antarctica Napier Tunguska |
genre |
Antarc* Antarctica East Antarctica ice core |
genre_facet |
Antarc* Antarctica East Antarctica ice core |
op_relation |
http://mnras.oxfordjournals.org/cgi/content/short/224/4/945 http://dx.doi.org/10.1093/mnras/224.4.945 |
op_rights |
Copyright (C) 1987, Oxford University Press |
op_doi |
https://doi.org/10.1093/mnras/224.4.945 |
container_title |
Monthly Notices of the Royal Astronomical Society |
container_volume |
224 |
container_issue |
4 |
container_start_page |
945 |
op_container_end_page |
951 |
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1766262589471326208 |