Now is the part where someone brings up even with the low relative velocity, you haven’t accounted for the simultaneity issues we’d have if the earth collided with a black hole while the rover landing was happening.
Or the fact that mars is not as deep in the gravity well of the Sun! I wonder if they have to account for that one when programming, like, antenna aiming or something.
IIRC gps suffers about 1hz of blueshift due to descending into earths gravity. I think the velocity (Doppler) shift of the spacecraft is a way bigger factor than the gravitational shifting.
