It depends what you want the viewer to focus most of their attention on. The first version emphasizes the man & clouds. The second version emphasizes the crater landscape in the background.
I think Lisa has it right. One can crop seven ways to Sunday and still make an effective statement. It is neither worse nor better, but a matter of what you want to emphasize and/or express. Having said that, some subject-matter, clearly guides the way a crop should go. I note in the larger version, the dark triangle strip has some information, which in the context of this powerfully graphic image is a distraction. I think the dark triangle should remain black as possible and reinforce the power of the silhouetted man in his environment.