Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Laser Ranging for Gravitational, Lunar, and Planetary Science   More precise lunar and Martian ranging will enable unprecedented tests of
Einstein's theory of General Relativity and well as lunar and planetary
science. NASA is currently planning several missions to return to the Moon, and
it is natural to consider if precision laser ranging instruments should be
included. New advanced retroreflector arrays at carefully chosen landing sites
would have an immediate positive impact on lunar and gravitational studies.
Laser transponders are currently being developed that may offer an advantage
over passive ranging, and could be adapted for use on Mars and other distant
objects. Precision ranging capability can also be combined with optical
communications for an extremely versatile instrument. In this paper we discuss
the science that can be gained by improved lunar and Martian ranging along with
several technologies that can be used for this purpose.

28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
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The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int