cclarry
B. at their CLOSEST they are 35 million miles...which has not been observed since we began keeping records.
This event (called 'Opposition') happens once every 26
months or so. Because Earth and Mars have slightly different orbital planes, and both move in ellipses of differing eccentricity, the distance between the two planets at opposition can be more than 35 million miles.
C. the TIME it would take for a RADIO wave to reach the Earth would be,
at their CLOSEST POINT, 34 days...given that the speed of sound at
Sea Level is 700 mph. ( I know that "space" is different ) just using this
as a reference point.
Radio waves travel at the speed of light, not the speed of sound. It would take a radio message just over 3 minutes to travel from Earth to Mars at opposition, and around 21 to 22 minutes when they are around their farthest apart (called 'Conjunction').
My point is...if you are trying to land a vessel on a planet that is AT IT'S CLOSEST
POINT some 35 million miles away, factoring in LAG TIME (let's call it "latency" ) for ANY SIGNAL, even LIGHT, to reach Earth. The landing would be impossible for someone HERE on Earth to perform....let alone observe, as, by the time Earth observes the landing, it should have ALREADY taken place quite a while PRIOR to the observation HERE on Earth.
I'm sure they have some SCIENTIFIC jargon to throw out there..
And I know the landings are COMPUTER controlled.
Well, that is roughly how it is done. They're not flying it in by remote control for the reasons you mention, but they will wait for certain telemetry and respond accordingly before 'authorising' the onboard computers to perform certain significant changes in trajectory.
But to say
we are WATCHING the landing in "real time" is a misnomer at best.
By the very fact that electro-magnetic waves (in this case light waves) travel at a finite speed, we don't really see
anything in 'real time'. True, the delay at short distances may be small enough to discount for practical purposes, but it is still there. At short light-distances, the time it takes for light waves to travel from the retina and be processed by the brain is more of a factor.