Mars Rover Stuck in a Dune

Bamfarooni writes "The NASA Mars rover Opportunity has gotten stuck in a dune, buried up to the hubs of the wheels. While they haven't given up yet, it doesn't look good for the little guy who's now 359 days into the extended mission." From the article: "The Mars machinery had been cruising southward across the open parking lot-like landscape of Meridiani Planum, full of larger and larger ripples of soil. Opportunity has been en route to its next stopover, Erebus crater, nestled inside an even larger crater known as Terra Nova."

Comments

Job well done

[witchman]

Too bad if it's permanently stuck, but what an amazing success for this mission, which has gone on far longer that it was planned for. I hope the NASA engineers get the recognition they deserver for this job well done.

Re:Job well done

[Rei]

When the Mars Rovers start launching 25K kg to LEO, you can start making that comparison. We're not even talking about remotely comparable classes of vehicles.

You know how new, large jet engines can cost millions of dollars, even though they're mass-produced? Picture an engine that dwarfs your typical jet engine in terms of complexity (in order to get such extreme performance - a single SSME no larger than a 747's engine could propel a 747 at 4 Gs, and still manages to be one of the most efficient rocket engines), and is not mass-manufactured, and you start to get an idea of what is involved here. Real rocket engines (we're just talking about the engines here - the rest of the craft is incredibly difficult, too!), as opposed to little joyride engines that use a heavy tank of nitrous and tube full of rubber, deal with some of the hottest (hotter than the boiling point of lead), most corrosive (high temperature hydrogen-rich thermodynamically imbalanced mixtures corrode things very easily), high vibration, very high thrust, and yet very maneuverable (for gimballing) environments that humans have ever produced. And to make it reusable? A truly incredible feat.

And to think that the fuel is LH (just barely above absolute zero - the temperature alone makes metals brittle - and hydrogen itself severely embrittles metals and leaks through almost anything), while the oxidizer is LOX (one of the most corrosive oxidizers you can get apart from LF). You need to not only contain them (and prevent ice from forming on these frigid structures without adding much weight at all), but to build your tanks with such a bare-minimum-thickness that if you were to turn many rockets upside down when full, they'd rupture due to the taper. These tanks need to be somewhat pressurized (although most pressure needs to be added in the turbopumps - amazing devices on their own). Every last pipe (and there are *many* of them), every last joint, must be as weak as possible, but still welded/attached security, uncorrodable, not allow ice buildup, not melt, and not be vibrated loose. And then, the structure overall is collossal - the whole thing needs to be built this way.

We haven't even gotten into reentry and the problems of being in space for a long time. It's really incredible that we can get off this rock at all; the term "rocket science" being used to mean "highly difficult problems" is quite apt.

Dear NASA & JPL

[computerme]

If any NASA or JPL people are reading this thread I have one thing to say:

Mission _very_ accomplished.

The human race knows infinitely more of our red neighbor thanks to your hard work.

THANK YOU!

Re:Dear NASA & JPL

[ajnsue]

I just linked to the pictures on the marsrover website. Gives you chills. /.'ers get into raving discussions about technology thats obsoleted in a few months. And somewhere, somebody is DRIVING A FREAKIN VEHICLE AROUND ON ANOTHER PLANET, TAKING PICTURES! ...geez i feel so insignificant, I need a hug.

Re:Dear NASA

[east coast]

If you had let Xzibit and West Coast Customs pimp out the Rover with 20 inch rims you would have avoided this problem.

Yeah, but the only thing they would have done to the drive train was put another quart of motor oil in a 25 year old Ford engine with 320,000 miles...

We'z gonna fix yo bucket!

Re:Change type of vehicle?

[stlhawkeye]

Considering the Martian soil is practially all sand (at least where they like to land) wouldn't it be better to use hovercrafts there? there's plenty of atmospheric gasses (CO2 mostly) and i think this doesn't get all that affected by dust.

Somebody else mentioned treads as well. I'm guessing these things were considered and discarded due to the extra complexity, weight, and power requirements of those modes of locomotion.