you don't need to hold on to the tether all the time. Linear motors on the car and embedded metal strips every 1 km and you have a Lunar rail gun :) In practi

you don't need to hold on to the tether all the time. Linear motors on the car and embedded metal strips every 1 km and you have a Lunar rail gun :) In practice the rotational speed difference at different altitudes will make it a bit more complex. But nothing that cannot be solved.