>Looks like she's returning to Home Plate

And not with Oberth, et al, in the Rear hazcam (forward-facing).

--Bill

I think they moved to the nearest patch that offered a slightly better tilt w.r.t. solar power for a few days of analysis - toward or away from HP, I doubt they cared much.

Doug

First impression: the right front wheel looks like it is locked.
But if you look at images from last year, you can see that Spirit created trenches when it traversed soft material.
Image from sol 313 for comparison
http://marsrovers.jpl.nasa.gov/gallery/all...00P0745R0M1.JPG
I assume for now that the wheel will turn when it meets enough resistance.

OH, Maannnnn. There is so much I don't know, it's scary!
OK I've never even dropped in at one of the other planets in UMSF. Until it went orbital, I'd never even seen the MRO section! My toolbar button goes straight to MER. The truth is I'm spending too much of my remaining 'fourscore and ten' already on the MER pages! But this is planetary science I can touch. This is almost as good as biology. (I can pay no higher compliment.) When I was an astronomer (age 7 - 10), I would have been able to quote chapter and verse of UMSF from A to Z. Time marches on.
Lavinia? Is that the ravishing name of that diaphanous 'flower' at upper left? Are they volcanoes? (I am as a newborn babe on this planet, but, PC be damned, I know a blessedly feminine place when I see it.)


Edit note: Now that I've studied the blowup, I assume they're impact craters. The radar makes the proximal ejecta look like flower petals! Cool.

http://static.flickr.com/41/113051772_e40da86735_o.gif
Nice animated anaglyph from the other forum, if you haven't seen it.

Jim Bell concluded his presentation in the morning session by mentioning that most recently they had taken diagnostic images of the wheel, and that Steve Squyres might have more to say when he speaks. After SS didn't mention it, all ll I could think was that they didn't know enough yet to speculate.

I had a short chat with Matt Golombek after the last presentation. Although I should have known better, I couldn't help but ask him if they had any ideas about the wheel problem. As you might expect, he told me it was too soon to speculate because it was such a recent development. He also said the engineers were investigating (again, something you might suspect). So, I wasn't able to learn anything new, but only confirmed what one would logically suspect.

...for what _that_ is worth.

The wheel is definitely looking dead (open circuit, consistent with a brush failure).

Without giving up on the motor, the most productive engineering effort will probably be enhancing the efficiency of 5-wheel-drive. The sol 781 drive took almost an hour to drive a total of ~4 meters, because of the need for visodom and other extra imagery. Their durrent energy budget only allows 1 to 1.5 hours of driving per day, so this gives you an idea of the pace you can expect.

Another drive is planned on sol 782.


My understanding is that it takes ~30 N-m (22 ft-lb) of torque on the wheel to overcome the detent. Good for holding position on slopes, but it now makes it unlikely that the wheel will ever turn again. Deeply embedded rocks could easily snare the RF wheel.

Oh dear...that's very bad news... Spirit's roving days are pretty much over then.

She's at the Lunar and Planetary Science Conference.

I was wondering where she had disappeared to.

Well, until next summer, at least.

> Well, until next summer, at least.

And don't discount their ability to come up with clever driving algorithms, that can improve efficiency without compromising safety.

I'm sure the MER engineers will be able to squeeze more meters out of future 5 wheel drives, so I don't think Spirit will turn into a lander mission just yet. It just looks like I'll have to give up my hope of seeing a pan from Spirit at the mouth of Ma'adim Vallis

That may be hoping for too much but I don't think that losing one wheel is catastrophic. The 4m progress rate is more a consequence of the visodm drive mode. In a fully planned or blind drive she should be able to go further if and when the circumstances and terrain allow.

On the plus side the rovers are scheduled to get a software upgrade in June. So the planning is still for the long term.

Yeah, I know that Ma'adim Vallis is not a realistic goal - I've just always fantasized about what a killer desktop image it would make