 What would have happened if Ledman had stayed on Earth?
The planet itself was tough enough—barren, desolate, forbidding; enough to stop the most adventurous and dedicated. Nothing but what had stopped us could stop a sandcat: sand in the delicate mechanism of the atomic engine. Maybe we shouldn't have come to Mars after all. I thought I knew everyone on sparsely-settled Mars. Earth needed radioactives, and the only way to get them was to get out and look. And that started the chain of events that led Val and me to end up as a madman's prisoners, on Mars. With every source of uranium mined dry on Earth, we had tried other possibilities. It's a stopgap effort, just to keep things moving until Project Sea-Dredge starts functioning.
 He might not have needed a wheelchair long-term
 He would've managed to maintain leadership of his company  He might not have needed a wheelchair long-term  He would have joined the Project Sea-Dredge mission  He would've become more depressed and never found revenge