Tires on the ground ...

Yeah, what he said.

Though, if you had sufficiently powerful braking rockets you could conceivably get it to low altitude without melting...so that it could then spectacularly collapse under its own weight and come crashing to the ground.

JR

The Mars balloon need not have a great deal of mass, its the strength of the shell that worries me. Now, the first privately sponsored ship into low earth orbit, didn't have a heat shield, it did it by constantly altering its drag. How to do that with a balloon presents problems. So, lets work out the minimum shell volume for mars, then make a very long thin vacuum balloon of that mass. So our payload travels round the planet like a migrating spider.

(edited) [] SpaceShipOne is sub orbital.

Why do we need this balloon?

Mark Vitrone

We don't [] but a vacuum balloon sound like fun. I do think we need to give some thought though to the mini Mongolfier balloon idea. We need to have one that stays up at night.

Here's a quick image of your rover "tank" model. I put the four front track wheels on an "L" shaped bar, and the dish right to the back. This way the tank could flip over and its wheel arrangement would be the same. The dish would have to flip 180 degrees. Perhaps we could put the camera lens at the top of the dish mount to give it a bit more height.

Now the diameter of the wheels on this model are 30 mm as per Larry's sizes but won't the view from such a small rover be pretty depressing?

<b>[Mark Vitrone] "Why do we need this balloon?"</b>

Stoat is right - we don't, but thinking about it is good mental exercise. IOW, fun. Out-of-the-box is frequently the equivalent of impractical. Until someone has an idea ...

That article was published back in the mid 1990s so it has been a while since I read it. It seems to me (but I'm not positive) that the author addressed most if not all of the objections that you guys have put forth. I'll dig through my back issues one of these days and see if I can find it.

LB

Stoat,

Thanks for the beautiful modeling job. One comment, I envisioned no empty space between the drive wheels of the tracks. This space would be good for adding mass for traction and placing sensors and power packs, (also no empty space means less chance of clogged or jammed tracks which is the major detraction from the design). A mast mounted fish-eye lens may generate good images. Also, 30mm is pretty small. This rover could be a total length of .4 meters and be a little more robust for scientific measurement. All in all thanks for the amount of effort you put into that, doing that kind of modeling is way out of my league, it makes my little power point stick drawings look so kindergarten.

Mark