0 sats \ 2 replies \ @ek 16 Oct 2022 \ parent \ on: I think we're all underestimating Bitcoin bitcoin
Yes, in one way and you are right, RTT (round-trip time) is the important one. But I just thought light would need 8 minutes for earth-moon (it's 1.3 seconds, therefore RTT is 2.6 seconds) but it was earth-sun.
For scale, it takes light 134ms to travel the diameter of the earth (if we had no atmosphere). Starlink LEOs' altitude is about 750 miles, which has a mean orbital circumference of 159 light-milliseconds. This is still better than ground transmission since the speed of light in free space is 50% faster than in fiber optic. In single-mode fiber, the circumference of the earth is 200 light-ms.
Curious the distance to the moon happens to be about 10x the circumference of the earth.
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I wonder if one built a large superconducting magnet on the poles of the moon, whether it would enable protection from the solar wind and potentially enable an atmosphere that could support some kinds of life.
Assuming atmospheric pressure is directly proportional to gravity and height, and the gravity of the moon is 1/6 of earth; With napkin math, this puts the potential atmospheric pressure at 1/36th of earth, or 0.41 psi. At this pressure, water is liquid between 32F and 71F. It's likely the moon is too close to the sun to sustain this low of an average temperature, but I don't know the principals behind computing that value.
If the atmosphere contained enough ozone, it might filter out enough UVC and X-rays. Under these conditions, and if somehow we could find a source of CO2, NH3 and O2, the moon could easily support plant life and begin building enough soil to feed any population.
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