I had forgotten about the merits of tethers vs space elevators. Far more practical.
I do recall a Blue Origin engineer remarking that the New Armstrong “rocket” wasn’t actually a rocket at all, but a “system.” Could Blue Origin be working on tethers?
For a tether designed to catch something in VLEO and boost it upwards, I prefer non-rotating tethers. You don't get as much of a delta-v boost and they require a large counter-mass, but you can make that counter-mass a space station you were already going to build, and they're much easier to rendezvous with. Rotating tethers are easier in higher orbits, or for places like the lunar surface with no air.
Yeah I agree that rotating tethers can't be much help getting to low orbits, touching the atmosphere makes them impractical. They really shine in doing transfers between higher orbits and planets.
Like you point out, the moon is particularly nice because there's no atmosphere and the lower gravity improves the scaling a lot.
I had forgotten about the merits of tethers vs space elevators. Far more practical.
I do recall a Blue Origin engineer remarking that the New Armstrong “rocket” wasn’t actually a rocket at all, but a “system.” Could Blue Origin be working on tethers?
For a tether designed to catch something in VLEO and boost it upwards, I prefer non-rotating tethers. You don't get as much of a delta-v boost and they require a large counter-mass, but you can make that counter-mass a space station you were already going to build, and they're much easier to rendezvous with. Rotating tethers are easier in higher orbits, or for places like the lunar surface with no air.
Yeah I agree that rotating tethers can't be much help getting to low orbits, touching the atmosphere makes them impractical. They really shine in doing transfers between higher orbits and planets.
Like you point out, the moon is particularly nice because there's no atmosphere and the lower gravity improves the scaling a lot.