Like, we’re destroying the one place we know is a sure bet on where we can prosper if we keep it healthy, but instead the world’s richest man is trying to expand to other planets while this one’s ability to sustain life is in jeopardy. IMO that makes us potentially a very stupid species compared to a species that doesn’t really care about meeting other aliens because they value the life on their own planet far more than we do.
i doubt that. the basic physics behind rocketry is well-understood. we know why electric propulsion cannot be used for lift-off (rocket equation), nuclear-thermal propulsion induces its own problems (nuclear waste), etc.
there’s just no way that you’re gonna circumvent the ways that physical laws push you into, even if we wait 300 years.
I don’t think it’s possible to know now that there won’t be significant developments in the next three hundred years. Tech savvy people in 1726 would have been looking at this, which I don’t think would give them enough information to make any useful predictions about how jet propulsion works.
Even the idea that non-ICE means electric- maybe in three hundred years, we’ll be have a new type of engine. Or maybe more likely, we’ll have a type of fuel that doesn’t pollute and it will be an ICE, just without emissions. Or maybe nuclear waste will be a solved problem.
We can’t know, but we do know that space flight is currently super pollutant, and continuing to launch rockets at the rate we have been is unsustainable.