alt Hacker NewsAn idea: use satellites for navigation. No, not the satellite signals, but the satellites themselves. Use NORAD orbital elements data for satellites to deduce land coordinates using time and pixel coordinates of satellites observed. Low orbit satellites will be only observable for two hours or so after sunset and before sunrise, but there are enough medium Earth orbit satellites that are still bright enough for a small camera and are visible whole night.
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m2fkxy • 01/21/2025
yeah, and then you need to get refreshed orbital elements for those satellites. not good if you are in an airtight environment.
celestial ephemerides don't change nearly as much.
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If you see satellites then likely you see even more stars. Unlike satellites the stars barelly move (actually they do, see "proper motion" [1]) relatively to each other, so a catalogue of stars (two coordinates values and two proper motion values) along with the time of observation is sufficient to be used over decades, unlike NORAD orbit elements requiring regular updates. With stars you need just one image at a known time to find your location, with satellites it is much much more complicated: you need to know where the sun is, you need few images of a satellite or even a video (likely on top of image of stars anyway) to distinguish it from the stars and to solve the trajectory.
1. https://en.m.wikipedia.org/wiki/Proper_motion