Let's see... pop cans, some zip tie hold-downs, chicken wire, part from various models, including most notably to my eye, the Klingon cruiser from the movies...
Gorgeous work, really! I love how a skilled modeler can take pretty mundane odds and ends and a nice paint job and whip something like this which looks very plausible. The rock-strewn field this stuff is set up on really sells it as an outpost on Mars.
I love it!
--Alex