[X] My Assistant

[anorthosite]

Let's suppose for the sake of discussion that a rover becomes immobile, but that its cameras and instruments still work. What's the best science you can do with a stuck rover? For example, you could do atmospheric studies indefinately; you could take closeups of everything within reach; and you could look for change over time at the site. Now chances are, we'll get rolling again, but maybe someday we'll face the question of salvage science. What's Plan B?

Steve Pendleton

[Bill Harris]

All of the above are good, bit I think that the best long-term use of an immobilre Rover would be to study long term weathering, erosional and depositional processes. We think we kow what is happening, but that is really an educated WAG...

I think she'll move on, though.

--Bill

[dvandorn]

All of the above are good, bit I think that the best long-term use of an immobilre Rover  would be to study long term weathering, erosional and depositional processes.  We think we kow what is happening, but that is really an educated WAG... 

I think she'll move on, though.

--Bill

I think she'll likely move on, too -- but if she doesn't, we're in a *very* interesting place to observe weathering and erosion.

It's pretty obvious from the layering being exposed in some of the larger dunes we just started seeing recently that *some* of these dunes are ancient and, instead of being built up, are currently being deflated. Unlike water erosion and aeolian erosion of rocks, dune erosion can happen over relatively short time frames. (Of course, it depends on the grain characteristics of the dunes and the "crusting" that may have occurred at the tops of the layers within the dunes.)

The fine striations visible transverse and sometimes perpendicular to the some of the dune crests suggests to me that these are the dunes that are being deflated. Note that some of these dunes display a "crumbling" appearance near their crests, where mass wasting has begin to pull material down -- another indication that the prevailing winds have changed and old dunes are now being blown away.

If a good, layered dune is within the reach of Oppy's IDD, perhaps a combination of the RAT and using the RAT head as a rough scoop will let us do very clean, long integrations of the different layers in the dunes. Wherever the grains forming the various dune layers originated, they will tell a story of changes in the Martian environment over time.

And careful observation of even minute (but detectable) changes in the dunes around Oppy would provide some really valuable data on the speed and characteristics of aeolian deflation/deposition on Mars, maybe even giving time frames for the formation of the layers in the ancient dunes. Thereby providing the possibility of putting absolute (if inferred) dates to recent Martian climate cycles.

So, if we have to become immobile somewhere, there are worse places...

-the other Doug

[Marcel]

If she can't get out, and if they send MSL to Meridiani, they might as well pull Oppy out in 2012, after 7 years of immobility in the dust. Then they shouldn't forget a Nilfisk though to clean her panels, lenses, etc...so she can continue for another 1000 sols

[Jeff7]

If she can't get out, and if they send MSL to Meridiani, they might as well pull Oppy out in 2012, after 7 years of immobility in the dust. Then they shouldn't forget a Nilfisk though to clean her panels, lenses, etc...so she can continue for another 1000 sols

That just seems cool - a nuclear powered rover with a winch pulling a small solar powered thing out. Send it to Sojourner next, and let the little thing ride along.


Better yet, use that Chemical Laser thingy (don't remember the name for it, can you tell?) and vaporize the sand near Opportunity's wheels.

[Marcel]

If she can't get out, and if they send MSL to Meridiani, they might as well pull Oppy out in 2012, after 7 years of immobility in the dust. Then they shouldn't forget a Nilfisk though to clean her panels, lenses, etc...so she can continue for another 1000 sols

That just seems cool - a nuclear powered rover with a winch pulling a small solar powered thing out. Send it to Sojourner next, and let the little thing ride along.


Better yet, use that Chemical Laser thingy (don't remember the name for it, can you tell?) and vaporize the sand near Opportunity's wheels.

That wont do a thing, since it'll vaporize microns of material over a couple of mm patch. It's called "chemcam".

But seriously, i'd consider an anchor and a mortar on MSL to fire it, so it can pull itself out incase it might get stuck....

[chokai]

But seriously, i'd consider an anchor and a mortar on MSL to fire it, so it can pull itself out incase it might get stuck....

Actually that is a very valid concern given the increased ground pressure under the wheels of a larger vehicle such as the MSL. Think about how a bulldozer can drive across the top of a muddy field and only sink in 5 or 6 inches when it weighs 10 tons but a pickup truck will sink right in to the hub caps almost instantly. The German's learned this well during World War II on the eastern front when the treads on thier Panzers were narrower, hence had a higher ground pressure and they sank into the mud/snow while the Soviet T-34's rolled on top of it.

I've operated some heavy equipment including a cat-325 exacavator and a much better solution is a robust trenching tool. If you get something with bucket on a boom like that stuck what you do is reach out as far as you can, slam it into the ground and then literally DRAG yourself out of the mud inch by inch. I once saw a 325 drag itself out of a peat bog where the top of it's treads were covered , it had sunk in almost 4 feet deep! Hydraulics (not sure how that would work on Mars) are amazingly powerful! Now with that kinda power on MSL we could do some serious damage. Like oh say flip over rocks. Ever wonder how big a rock like say old Adirondack really is? We could dig 3 foot deep trenches and get a good idea of the depositional rates of the sand on Mars.. Caterpillar could sponsor! :-P I believe MSL was going to have a trenching capability but I hadn't read anything about it recently, and I doubt it would be that powerful.