Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observatories in Space   Space observatories are having major impacts on our knowledge of the
Universe, from the Solar neighborhood to the cosmological background, opening
many new windows out of reach to ground-based observatories. Celestial objects
emit all over the electromagnetic spectrum, and the Earth's atmosphere blocks a
large part of them. Moreover, space offers a very stable environment from where
the whole sky can be observed with no (or very little) perturbations, providing
new observing possibilities. This chapter presents a few striking examples of
astrophysics space observatories and of major results spanning from the Solar
neighborhood and our Galaxy to external galaxies, quasars and the cosmological
background.

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The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
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The categories of this paper are: econ
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th