We've been very curious to figure out what they are.

Wind has to be involved at some level you figure. Frost might have helped. A frost build-up on arrays could coagulate the dust...but the fact is that we don't understand it very well. But I'll take it.

[Before launch] it just seemed impossibly far away, it seemed unreachable. Tonight, I go out knowing our rovers have been there a whole Martian year...it's a much more familiar planet. We know the place.

There are cliffs the rover could fall over and die if we aren't careful. We are gong to proceed carefully and methodically.

That's no Mt. Everest, but it's a heck of a climb for our little rover, ... When we first touched down at Gusev Crater on Jan. 4, 2004, the Columbia Hills looked impossibly far away.

That's no Mount Everest, but for a little rover this was a heck of a climb,