Is it really necessary to send humans to those places just to get the knock-on benefits? Couldn’t we do those things directly, without going there?
It seems to me that, today, those who have the money to spend on these endeavors would only do so if there were perceived short-term benefits to themselves. That means they plan to exploit the resources, or increase their own power somehow.
I know the good engineers that make this happen are doing it for the challenge and in the pursuit of knowledge, and I know that’s why we poors support it, but that doesn’t “pay the bills.” What is the motivation behind the money? Why are they really doing this?
Hopefully, but we’re not a very forward-thinking species. More likely we’d only give haulers just enough fuel to make gravity-assisted trips (which are only possible when orbits match up optimally) because it’s cheaper that way, making on-demand interception unlikely.
Destruction doesn’t always work either. If it’s struck close to Earth most of the fragments will still hit, and even if they’re too small to survive reentry they will still dump tons of heat energy into the atmosphere.
Physics is a harsh mistress.
I wonder how much heat energy fragments would actually dump and if it would be statistically significant. Somebody do the math!
I couldn’t find any hard values, but Wikipedia does have a chart displaying the energy asteroids of various sizes would release if they exploded before hitting the ground, as well as the total kinetic energy they’d have upon hitting atmosphere. All that energy would still have to go somewhere even if it’s fragmented.
I also found that a single 50 meter fragment is enough to destroy an entire city and surrounding metropolitan area, so even if the heat isn’t an issue you’d still have to somehow ensure zero large fragments survive interception.