> response that just hand-waves a bunch of really hard problems or invents tech that doesn't exist
The tyranny of the rocket equation is irrelevant to the problem of extraterrestrial manufacturing, at least in the short term. It’s all ISRU.
> Has there been legitimate significant progress on orbital guns or space elevators since 2012
Actually, yes. I’m sceptical of SpinLaunch. But they are making real progress on the technology, even if they aren’t the ones to complete the package to orbital delivery.
The tyranny of the rocket equation is irrelevant to the problem of extraterrestrial manufacturing, at least in the short term. It’s all ISRU.
> Has there been legitimate significant progress on orbital guns or space elevators since 2012
Actually, yes. I’m sceptical of SpinLaunch. But they are making real progress on the technology, even if they aren’t the ones to complete the package to orbital delivery.