Earth, this hunk of material orbiting the sun, doesn't need saving. It's also unlikely that anything would scratch it's life bearing capacity too. Life has weat

Earth, this hunk of material orbiting the sun, doesn't need saving. It's also unlikely that anything would scratch it's life bearing capacity too. Life has weathered big mass extinction events. It looks quite resilient. So I assume by saving earth you mean saving earth's ability to sustain human society. It's a great goal! So how we do that? What's the plan with asteroids for example? It wouldn't surprise me if by doing all the necessary research and engineering to make a stable mars settlement possible we would make leaps toward a sustainable life here on earth too. After all you won't live there by wasting your resources.