Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Motivation and possibilities of affordable low-frequency radio
  interferometry in space   The motivation to build spaceborne interferometric arrays for low-frequency
radio astronomy is widely recognised because frequencies below the ionospheric
cutoff are inaccessible for ground-based radio telescopes. We discuss the
theoretical possibilities to use low-frequency spacecraft arrays to detect
signals from magnetized extrasolar planets, including earthlike ones. A major
uncertainty that prohibits us from knowing if it is possible to detect
exoplanet cyclotron maser signals is the incomplete knowledge of the properties
of the interstellar plasma.
  We also present some ideas of how to construct efficient and affordable
space-based radio telescopes. We discuss two possibilities, a log-periodic
antenna in the spin plane and a two-spacecraft concept where one spacecraft
holds a large parabolic wire mesh reflector and the other one contains the
receiver. In the latter case, the effective area could be of the order of 1
km$^2$. The purpose of the paper is to stress once more the importance of
spaceborne low-frequency measurements by bringing in the intriguing possibility
of detecting earthlike exoplanet radio emissions and to demonstrate that
building even very large low-frequency antennas in space is not necessarily too
expensive.

9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: eess
27
The categories of this paper are: comp-gas