Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comments regarding William Herschel April 1787 report of an erupting
  volcano on the moon: were these observations the manifestation of Impact
  Melt, produced by a meteorite from the Lyrid meteor shower?   We consider that the report by William Herschel on April 19 and 20, 1787,
about an erupting volcano on the moon were really the observations of impact
melt, produced by a meteorite from the Lyrid meteor shower. According to our
investigation the probably resulting crater of this event is a lunar cold spot,
with coordinates similar to those given in Herschel report, and we also argue
that this impact has very young characteristics.

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The categories of this paper are: nucl-th
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The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
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The categories of this paper are: chao-dyn