If you had a ladder stretching all the way into space, you could climb it without needing any rocket propellant
On the moon it's just about doable with current technology and realistic levels of mass.
Paging Larry Niven...
A ring with a diameter matching your skyhook's length might seem to need 22/7 times the mass lofted to orbit, but the stresses on it are much less complicated, so it may be lighter than that. You may imagine one rolling around Earth, dipping to 100 km and flinging off whatever grabs on at up to 10 mi/s.
BTW, I calculated that the tensile strength of the material of any rotating ring, whether girdling the sun like Niven's, or just orbiting the regular way like a Halo or Culture "orbital", must be enough to support against its inside surface "gravity" a full radius's length of the material.
So, a ring rotating to provide 1G and taking 24hrs to do it (so days are the right length), would have to be about 2M km in radius. It would therefore need to be made out of something that could support a 2M km long constant-thickness cable against 1G, or more than 100x as strong as what you would need for an earthly space elevator.
A ring of 100 km radius rotating so that its tangential velocity matches earth orbital velocity less earth's rotation, 7.5 km/s, accelerates anything that latches onto it at 560 m/s^2, or 55 G. One at 1000 km radius would pull 5.2G, a little less strenuous for puny humans; they would need to endure it for a few minutes until flung off. That one would need to be made of stuff that could hold up 5200 km of itself, which might be just within range of what we can make.
Methods for dodging satellites are left as an exercise for the reader.
Will be interested if you have any studies on it.
http://hopsblog-hop.blogspot.com/2016/08/lunar-sky-hook.html
https://hopsblog-hop.blogspot.com/2016/04/liftport-lunar-tet...
There's also a wikipedia article:
The catch is that nobody can actually build a ladder strong enough. Space elevators from Earth require sci-fi materials.
You might even be able to take advantage of this by chilling the compressed air before it goes into the beanstalk, so that it absorbs heat from the surrounding air on the way up. Or have separate pipes with one carrying methane to burn as fuel. Lots of options to evaluate.
Yes, we've ruled out aluminum and wood. But don't give up! Got any single-crystal graphene? That might work!
"Real" versions of this scheme would use laser power beaming. Of course, a "real" version of the scheme would also need hefty rockets on the passenger vehicle to keep them from dying if the vehicle fell off the ladder (or if the ladder broke). The rockets are needed to either slow the vehicle before atmospheric entry (so the deceleration is not fatal) or thrust sideways to put the passenger pod into elliptical orbit that just misses the atmosphere. The delta-V needed at the worst case altitude is non-negligible.