There are 33 GPS satellites, and they are in a medium orbit, not LEO. Which is not to say they are invulnerable, but compared to jamming or spoofing, I think the satellites themselves are considered one of the less likely points of failure (or attack) of the system.
24 is the minimum number, 33 is the target number, there are currently 31 active, and 9 in testing/reserve some of which could be activated if need be.
(according to Wikipedia, this discussion got me to read more about it)
I'm just curious what people think about this imaginary scenario.
Let say an opponent already have satellites in space with laser weapons, could they just destroy the GPS satellites using such a tech ? Or do you guys think that this technology does not exists ?
We saw some videos in recent years of NASA laser weapons taking down planes. That's why I'm thinking about this. Maybe the distance in space would make it impossible... I have no clue.
It would still has line of sight to deal with so you would either need a bunch of them or some type of maneuverability. It would be easier to just shoot a rocket it at.
Line of sight wouldn't be an issue, range and aiming would be the problem. The GPS satellites are in a bunch of orbital planes so a weapon wouldn't try to rendezvous with each target, it would need to hit them from another orbit. The solution would be to launch the weapon in a lower orbit and just wait until each target comes within range.
If aiming a laser accurately is too tough of a challenge (probably is) then as an alternative you would need 6 weapons and launch each one in one of the 6 orbital planes that the GPS constellation uses and just have a little bit lower orbit than the GPS satellites so it would come around and catch up to each satellite but not be travelling so fast as to make accurately aiming impossible.
Lasers delivering enough energy to be useful as a weapon are limited in range by diffraction; for a satellite-launchable laser, this on the order of hundreds of kilometers.
2. In very small numbers (at most one in orbit at a time).
3. Recoverability of payload.
4. Very high delta-V (i.e. can shift orbits a lot, and has been observed doing so in big jumps during deployments).
The most likely guess is a testbed for military satellite subsystems; put a camera or a radar on there, and you can get a feel for its performance at different altitudes/angles, and also bring the prototypes back down to do a teardown after the fact.
