 Which term best describes Mars' population?
The planet itself was tough enough—barren, desolate, forbidding; enough to stop the most adventurous and dedicated. No, we had decided together to come to Mars—the way we decided together on everything. I watched her, sleeping peacefully, a wayward lock of her soft blonde hair trailing down over one eyebrow, and it seemed hard to believe that we'd exchanged Earth and all it held for us for the raw, untamed struggle that was Mars. I thought I knew everyone on sparsely-settled Mars. And that started the chain of events that led Val and me to end up as a madman's prisoners, on Mars. So, Mars. There's not much uranium on Mars, and it's not easy to find or any cinch to mine.
 meager
 congested  meager  sustainable  uninhabited