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تسجيل مستخدم جديدTowers on the Moon: 1. Concrete
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The lunar South pole likely contains significant amounts of water in the permanently shadowed craters there. Extracting this water for life support at a lunar base or to make rocket fuel would take large amounts of power, of order Gigawatts. A natural place to obtain this power are the Peaks of Eternal Light, that lie a few kilometers away on the crater rims and ridges above the permanently shadowed craters. The amount of solar power that could be captured depends on how tall a tower can be built to support the photovoltaic panels. The low gravity, lack of atmosphere, and quiet seismic environment of the Moon suggests that towers could be built much taller than on Earth. Here we look at the limits to building tall concrete towers on the Moon. We choose concrete as the capital cost of transporting large masses of iron or carbon fiber to the Moon is presently so expensive that profitable operation of a power plant is unlikely. Concrete instead can be manufactured in situ from the lunar regolith. We find that, with minimum wall thicknesses (20 cm), towers up to several kilometers tall are stable. The mass of concrete needed, however, grows rapidly with height, from $sim$ 760 mt at 1 km to $sim$ 4,100 mt at 2 km to $sim 10^5$ mt at 7 km and $sim 10^6$ mt at 17 km.
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The Earth-Moon system is unusual in several respects. The Moon is roughly 1/4 the radius of the Earth - a larger satellite-to-planet size ratio than all known satellites other than Plutos Charon. The Moon has a tiny core, perhaps with only ~1% of its
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Moon-magnetosphere interaction stands for the interaction of magnetospheric plasma with an orbiting moon. Observations and modeling of moon-magnetosphere interaction is a highly interesting area of space physics because it helps to better understand
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Next-generation missions designed to detect biosignatures on exoplanets will also be capable of placing constraints on the presence of technosignatures (evidence for technological life) on these same worlds. Here, I estimate the detectability of nigh
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The Peaks of Eternal Light (PELs), that are largely unshaded regions mostly at the lunar south pole, have been suggested as a source of solar power for mining the water and other volatiles in the nearby permanently dark regions. As mining is a power-
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