Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Incorporation of a Late-forming Chondrule into Comet Wild 2   We report the petrology, O isotopic composition, and Al-Mg isotope
systematics of a chondrule fragment from the Jupiter-family comet Wild 2,
returned to Earth by NASA's Stardust mission. This object shows characteristics
of a type II chondrule that formed from an evolved oxygen isotopic reservoir.
No evidence for extinct 26Al was found, with (26Al/ 27Al)0 < 3.0 x 10^-6.
Assuming homogenous distribution of 26Al in the solar nebula, this particle
crystallized at least 3 Myr after the earliest solar system objects--relatively
late compared to most chondrules in meteorites. We interpret the presence of
this object in a Kuiper Belt body as evidence of late, large-scale transport of
small objects between the inner and outer solar nebula. Our observations
constrain the formation of Jupiter (a barrier to outward transport if it formed
further from the Sun than this cometary chondrule) to be more than 3 Myr after
calcium-aluminum-rich inclusionss.

31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
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The categories of this paper are: math-ph