Minimal mass of an Earth-like satellite to seriously deter space travel?
I want to write a story taking place on the natural satellite of a gas giant, with said satellite being massive enough to prevent, or at least strongly deter, space travel, such that the resources needed to achieve orbital velocity would be too great to consider it lightly.
Its peoples' technology would be at least as advanced as our own, and preferably quite more advanced.
Its gravity (or atmosphere) would also hopefully impede animal flight (at least for any animal bigger than an insect).
It would be fine (though not ideal) if they could send non-living things to space.
So far, I only know that the different obstacles could be that:
- More efficient fuel is too dangerous to handle.
- More efficient fuel is rare or very hard to mine on this satellite.
- The acceleration needed to reach escape velocity would kill anyone inside the rocket/launch loop/exotic propulsion device.
- The atmosphere itself impedes rocket launches.
- No one wants to invest in a space program, because the project is simply too expensive and the results uncertain.
What are the minimal requirements (in terms of mass, atmosphere, or whatever else you can think of) of an Earth-like satellite for its inhabitants to give up on space programs for a long, long time?
Many thanks in advance!