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arXiv · 2307.11616

Lunar Far-Side Radio Arrays: A Preliminary Site Survey

Zoe A. Le Conte·Martin Elvis·Philipp A. Gläser
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Abstract

The origin and evolution of structure in the Universe could be studied in the Dark Ages. The highly redshifted HI signal between 30 < z < 80 is the only observable signal from this era. Human radio interference and ionospheric effects limit Earth-based radio astronomy to frequencies > 30 MHz. To observe the low-frequency window with research from compact steep spectrum sources, pulsars, and solar activity, a 200 km baseline lunar far-side radio interferometer has been much discussed. This paper conducts a preliminary site survey of potential far-side craters, which are few in number on the mountainous lunar far-side. Based on LRO LOLA data, 200 m resolution topographic maps of eight far-side sites were produced, and slope and roughness maps were derived from them. A figure of merit was created to determine the optimum site. Three sites are identified as promising. There is a need to protect these sites for astronomy.

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Zoe A. Le Conte, Martin Elvis, Philipp A. Gläser. 2023-07-21. Lunar Far-Side Radio Arrays: A Preliminary Site Survey. https://doi.org/10.1093/rasti%2Frzad022

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