> Satellites don’t orbit on the ground, which makes the 40m spacing nonsense.

Hence why the horizontal scale bar says "40 m to 43 m": Going to 500 km doesn't add much to the orbit's circumference.

> And nobody proposes putting a million 120 kW satellites in a single orbit.

One of my tentative conclusions is that it would be an improvement if they did. But also, there's better contiguous structures to build if you could put that much up.

It's in my blog post because I'm considering all possible arrangements of ways to do this. Current list:

  • Spread them out by altitude while still keeping them in sun-synchronous low earth orbit like SpaceX plan
  • Put them all of them in a single sun-synchronous low earth orbit so none of them can hit each other
  • Spread them out like Starlink currently is
  • Have swarms, where each group has many satellites significantly closer to each other than the usual safety separation, like Google's Project Suncatcher
  • Have fewer, bigger satellites, like Starcloud

Matters less than I expected when I started writing. How much so depends on what I end up adding by treating gaps in "full" (up to the safety margin) orbits as the thing of interest and seeing if someone's done a version of this on spherical geometry and also add a time component: https://math.stackexchange.com/questions/270937/how-can-you-...

(That I'm researching such questions should explain both why I'm at 7k words and why I've not published it yet).

(One big surprise to me while researching this: along-track, cross-track, and radial positional error per unit time are all much higher than I would have guessed: https://digitalcommons.usu.edu/smallsat/2015/all2015/58/).