No, they're not.
LEO is an orbital period of 128 minutes or less, which for circular orbits is ~1200 miles or less [1]. GPS satellites are in 12 hour orbits ( see "Orbital Characteristics" in [1], putting them at a little more than 12,500 miles out [2].
And anyway, a satellite's altitude has little to do with how soft a target it might be. It's not simple.
That said, I'm glad training emphasizes non-GPS modalities. You never can tell when Carrington will come calling [3].
[1] https://en.wikipedia.org/wiki/Low_Earth_orbit [2] https://en.wikipedia.org/wiki/Global_Positioning_System [3] https://en.wikipedia.org/wiki/Solar_storm_of_1859
(according to Wikipedia, this discussion got me to read more about it)
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.
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.
Its design features are:
1. Long-duration flight (low-single-digit years).
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.
As to technical details, here is a write up of the NAS26 astro-inertial guidance system from the '70s:
http://www.dtic.mil/dtic/tr/fulltext/u2/a090649.pdf
The navy and the air force get all the coolest toys, I tell you what.
[0] https://timeandnavigation.si.edu/multimedia-asset/nortronics...
[1] https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c...
On either side?
And anyways, what country has the budget to knock out twenty four satellites in quick succession?
And what if this doesn't work? I'm having a hard time thinking the US Gov. doesn't have a shadow GPS constellation up there, somewhere, but I will concede this is the most wahoo part of my meanderings...
I think knocking out GPS is a rather risky move to even try.
The only countries between whom a war would be a globally consequential event: the United States, China, and Russia.
And that is quite a few: Israel, UK, France, India with North Korea/Iran not that far behind.
It's not very easy to do.
And of course to get around that, is to put your own sat. nav. system together.
The US military uses very advanced and highly classified inertial navigation technology for both guidance and navigation systems pervasively. GPS was just a way to collect the data required to make inertial guidance effective. The US military has never relied on GPS for anything; the Soviets could destroy it the day it was designed, so it wasn't designed for war.
When they can get it, GPS reduces error, though I agree that systems are designed to be tolerant of jamming and shootdowns.
China and USA. Any war that they don't participate in is anyway irrelevant on the global scene.
[1]https://spacenews.com/spacex-targeting-24-hour-turnaround-in...
Another option would be hacking the enemie's GPS-like system. I assume we're already hard at work on that.
They don't have to take them all out at once. Just the threat of the system going sown at any time is enough to make it unreliant.
as well as the system of the US allies (EU) and if you do that, you're in hot water with those allies.
I say, good luck with that, sir.
I think 24 missiles pointed at earth targets would have more impact than some pesky satellites.
You will already be in a lot of hot water if you're in a war with the US. The countries who have the capability of doing this have thousands of missiles. A hundred of them being used to knock out some sats is nothing.
And again, what if it doesn't work? You can only try this one time. After that, you lose your element of surprise. Your enemy now knows the enormity of your intent to do harm. Lesson to be learned from Pearl Harbor.
Risky. Risky. Risky.