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What I should have been looking at is the Geoid of Mars & the depth from it to the mantle The thickness of the crust varies between 50 km & 22 km due to the Geography & features (rock layers) above the Geoid while the distance from it to the mantle should be reasonably uniform. I presume the putative Geoid of Mars is the altitude used for ...

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There isn't a problem with sunlight supply at the south pole. It's actually the opposite situation. One of the biggest attractions to the lunar south pole (after water) is the fact that there are areas there that are in almost constant sunlight. From the rim of Shackleton crater, the sun skims the horizon to a complete 360˚ as the lunar day progresses. It's ...

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The answer is no, you cannot have a static satellite. It would require high delta-V continually thrusting the mirror upwards. Solar sails do not have high delta-V. But that is okay - if all you want is polar moonbase illumination, that problem is already solved: Solution 1 - Have a network of satellites with mirrors, and use them in turn as they pass near ...

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A more generic answer could be: Angular speed (constant in any point on surface) is 2*pi radians every 29.53*24 hours, which gives 0.00443 rad/h. Linear speed depend on local distance from rotation axis, which is r * cos(latitude). Hence linear speed in any point on Moon surface is: v = 0.00443 * r * cos(lat) [rad/h]*[km] Of course for lat=0° it ...

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Using the diameter 3476 km and the Moon solar day of 29.53 Earth days I calculated a speed of 15.4 km/h for the day night line at the Moon equator. $$\frac{3476 km*π} {29.53*24 h} = 15.4 km/h = 4.28 m/s$$ That is the necessary average speed at the lunar equator to stay in eternal day light. A rod is 5.0292 m, so a rod per moon-hour is 0.0473 mm/s A ...

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Maybe not directly related to the question, anyway this site allows calculating "what time it is" in a specific location on the Moon: http://win98.altervista.org/space/exploration/moon/moontime.html In this page, the moon day duration (29.53 days) is divided into 24 moon-hours; when sunrise terminator reaches specified point, local time will be 06:00; when ...

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