45 years ago this month Dr. Gerard O'Neill testified to congress on his proposals for our future in space, presenting his ideas for manufacturing in space, solar power satellites, and free-space habitats a the L5 point in Earth-Moon space. This was big stuff at the time amongst those of us interested in space travel, but seems to have faded into the background these days. I think these ideas need to be brought back to the forefront and given another look. A video about the Bernal Sphere type of colony: Here's a good video talking about the O'Neill Cylinder type of colony: And here's a link for a page with a lot of resources if you want to dig deeper: https://space.nss.org/settlement/nasa/ Why schlep out of our own gravity well and go all the way to Mars just to climb down into another gravity well that'll need to be terraformed? Why not just build a bit more locally without the hassle of gravity?