[waterlesscloud]

Replying to myself. I asked Emily Lakdawalla on Twitter. She's a journalist for The Planetary Society website, has great info on all the rover stuff.

Rodney Ramsey: @elakdawalla Maybe you can answer a curious Q for me... Why does Mars dust stick to Curiosity's wheels?

Emily Lakdawalla: @RodneyRamsey Electrostatic! The dust is extremely fine, Mars super dry.