If they can get rockets to mars, what’s to prevent them from deploying GPS satellites around Mars? Then just have the spacecraft switch to receiving those signals instead as it get close enough
Nothing to prevent it except money. The issue with PNT satellites around Mars is how many satellites would have to be sent (smaller planet and less accuracy needed, so maybe we could get away with 12 instead of 24), plus the ground command and control stations plus monitoring stations. The ground part is probably the most critical piece of why GPS is so accurate, and I’m not sure we could do that from Earth. Definitely couldn’t do the monitoring from Earth.
We’d have to be able to build an accurate ephemeris table for the Mars satellites, have accurate clock updates, monitor the signals being transmitted to do updates, etc. While we could do the commanding and controlling from Earth, I don’t know if we could do the things from Earth that make GPS accurate. So not only would we have to send 12 satellites to Mars, we’d have to build monitoring stations on Mars to do the ground portion. Technically doable, just not financially feasible when we have star trackers and other navigation systems that work well enough for now.
If they can get rockets to mars, what’s to prevent them from deploying GPS satellites around Mars? Then just have the spacecraft switch to receiving those signals instead as it get close enough
Nothing to prevent it except money. The issue with PNT satellites around Mars is how many satellites would have to be sent (smaller planet and less accuracy needed, so maybe we could get away with 12 instead of 24), plus the ground command and control stations plus monitoring stations. The ground part is probably the most critical piece of why GPS is so accurate, and I’m not sure we could do that from Earth. Definitely couldn’t do the monitoring from Earth.
We’d have to be able to build an accurate ephemeris table for the Mars satellites, have accurate clock updates, monitor the signals being transmitted to do updates, etc. While we could do the commanding and controlling from Earth, I don’t know if we could do the things from Earth that make GPS accurate. So not only would we have to send 12 satellites to Mars, we’d have to build monitoring stations on Mars to do the ground portion. Technically doable, just not financially feasible when we have star trackers and other navigation systems that work well enough for now.
Nice. That’s the detail I was hoping someone would have! Thank you