We knew the rover was gonna be a central element. We wanted to give people some eye candy and go sightseeing, so we knew we had to get away from the base, which after about day three is gonna have so many footprints and rover tracks and tele-operated rover tracks all over it that it's gonna look like the Mars Society convention was actually held there. Woodstock 2014.

So what happens when you start imagining the rover? You start figuring out what it needs to be, you start figuring maybe 10-day to 2-week sortie capability, the size of the tankage involved to have some decent range, redundancy systems, life support, storage for food, a little galley and all that sort of thing, and when you start working around an airlock and that kind of system, it starts to be a certain size. It's not an SUV-size rover. Ours is 22 feet long. I think it was called a Winnebago class rover.

One thing I want to mention while we have it here is the manipulators. I've spent hundreds of hours in a submersible, kind of mowing the lawn with a toenail clipper going across the sea floor. And it strikes me that the paradigm on Mars is gonna be fairly similar. You're gonna move along slowly, looking more down than forward, and you're gonna stop when you see something. And I think a lot of the work that people might think would have to be done on EVA, could actually be done from inside the rover.

I'm not saying, 'Let's not do EVAs'. I mean, you need a robust EVA capability but 500 days of EVAs could get old, I think. And could get dangerous. We still need data on what happens with the suits and so on when they're subjected to that kind of long-term exposure to dust and all that sort of thing.

So, we're gonna have a sample-collecting tray, like you'd have on a submersible, that can slide in and out. And the manipulators can put samples in. We're gonna show a little lock-in capability that they can actually lock directly in a sample, a small lock in the front.

What occurred to us after a while was that with the long-range capability and the cruise support required from a robust pressurized rover, it starts to basically look a lot like a full-on spacecraft. It has to be able to function reliably and with redundancy for up to two weeks in the air-vacuum conditions, thermal extremes and all that sort of thing.

So this led us to the idea that it could, in fact, function as a spacecraft and a lander by having a drop pack of decent engines that are clustered underneath, where the strut suspension could actually be used as your landing struts.

We don't know if they'll ever really do anything like this. It seemed like a cool idea. It's visual and I think it's technically justifiable, if not necessarily the very best thing to do. And of course there are a lot of mission architecture issues with respect to doing this.

-- from James Cameron's address to the International Mars Society, August 1999