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> First, Low Earth Orbit is at least 160km above the Earth. You could do it at 100km but now you have to fight atmospheric drag on top of everything else and co

> First, Low Earth Orbit is at least 160km above the Earth. You could do it at 100km but now you have to fight atmospheric drag on top of everything else and constantly need to readjust your orbit to avoid burning up. I am just thinking out loud but what if we went out further and added an array of satellites in the geostationary orbits, not to power anything on earth but rather to power each other. I was thinking if we had enough of these satellites and they were in line of sight between each other, could they kind of send power to each other in case one of them was in the dark? Just thinking out loud.

Renaud 4y ago
Geostationary orbit is 36000km. Imagine the amount of power you would need to concentrate to be able to create a beam of energy small enough to hit a target that is zipping by 36000km below. And these geostationary satellites would still be in the earth's shadow. Even the moon gets in the earth's shadow, and it's more than 10x the distance. You would need to have a bunch of satellites that can bounce energy to the target at low angles (so longer distances) which makes losses a lot worse and the problem even more complex. Others have also mentioned that the claim of achieving 60% efficiency at 1km looks dubious. Look at the pictures of the size of the antennae needed to basically run a couple of toasters... extrapolate even just a bit to compensate for the orders of magnitudes in range.
- DennisP 4y ago
  I agree we won't be powering individual vehicles from orbit, but geostationary satellites don't go in shadow for most of the year. The reason is that the Earth's axis is tilted with respect to its orbit around the sun. The only times the satellite is shadowed are around the equinoxes, for a total of 88 days per year with most of those days only shadowed a few minutes, and a maximum of 72 minutes on the equinoxes. https://www.viasat.com/about/newsroom/blog/how-satellites-are-affected-by-the-spring-and-autumn-equinoxes/ https://www.viasat.com/about/newsroom/blog/how-satellites-ar...

Renaud 4y ago

Geostationary orbit is 36000km. Imagine the amount of power you would need to concentrate to be able to create a beam of energy small enough to hit a target that is zipping by 36000km below. And these geostationary satellites would still be in the earth's shadow. Even the moon gets in the earth's shadow, and it's more than 10x the distance. You would need to have a bunch of satellites that can bounce energy to the target at low angles (so longer distances) which makes losses a lot worse and the problem even more complex. Others have also mentioned that the claim of achieving 60% efficiency at 1km looks dubious. Look at the pictures of the size of the antennae needed to basically run a couple of toasters... extrapolate even just a bit to compensate for the orders of magnitudes in range.

DennisP 4y ago
I agree we won't be powering individual vehicles from orbit, but geostationary satellites don't go in shadow for most of the year. The reason is that the Earth's axis is tilted with respect to its orbit around the sun. The only times the satellite is shadowed are around the equinoxes, for a total of 88 days per year with most of those days only shadowed a few minutes, and a maximum of 72 minutes on the equinoxes. https://www.viasat.com/about/newsroom/blog/how-satellites-are-affected-by-the-spring-and-autumn-equinoxes/ https://www.viasat.com/about/newsroom/blog/how-satellites-ar...