Printable Version of Topic

Posted by: sattrackpro Feb 28 2006, 05:17 PM

It seems it might be time to start a post about the run to the hills... there are few days left to get Spirit to a winter-friendly spot somewhere up there - with all those tempting spots that we ~might~ be able to stop by on the way. That is - if we don't dally too long at each!

A discussion of what the best spot would be, and why it would be the best spot seems in order - along with what the best targets on the way would be interesting.

I'm looking forward to the possibility that we'll have a chance to see several outcrops that appear to have layers, maybe similar in some respects to HP. Or will they be?

I'm also looking forward to the possibility that we might get a look from the top of these hills, off to the South as winter ends, before we descend from the hills and head to the "Promised Land."

Later I'll post some snips of locations I'm hoping to see up-close... thought I'd get it done on posting - but, just had an 'emergency' that demands quick departure!

Posted by: Tesheiner Feb 28 2006, 05:44 PM

I think I'll be the first to use this new thread...

Sol 766 drive images are available at the exploratorium: http://nasa.exploratorium.edu/mars/spirit/navcam/2006-02-28/


And the answer to the drive-direction is "clockwise". My guess is Spirit will NOT complete the circle but simply head to McCool hill.

Was there a song from Iron Maiden: "Run to the hills, run for you life" ?

Posted by: mhoward Feb 28 2006, 05:55 PM

Here's some views from Sol 766 (I'd set it to "On the Run" by Pink Floyd, maybe):

http://flickr.com/photo_zoom.gne?id=105880390&size=o http://flickr.com/photo_zoom.gne?id=105880376&size=o&context=photostream http://flickr.com/photo_zoom.gne?id=105880362&size=o&context=photostream

Here are the Pancam drive direction images in context (Tesheiner you can correct me if I'm wrong and they aren't drive direction images, as I didn't actually check the tracking database, but it seems like a pretty safe bet):

http://flickr.com/photo_zoom.gne?id=105880371&size=o&context=photostream

Posted by: Bill Harris Feb 28 2006, 05:57 PM

The Winter Retreat to a favorable slope is not necessarily a bad thing. There are several exposures on McCool Hill which might be related to HP and would be good to examine. In order to decipher HP we need to look at the lateral extent of the HP deposits. I wish we had the time to have stopped at the light-toned layered outcrop on the hill just south of Ultreya-ElDorado Basin: that may have been part of the HP Formation. And from atop McCool Hill we can get another set of Pancams from a different perspective.

I'm thinking move northeastward the north-facing slope of McCool Hill, work that slope during the Winter, moving southward along McH later in Winter and work down the western slope of McH, returning to HP in the Spring for followup observations. Over the Summer drive toward the Promised Land locality

I'll work up a map later tonight when I get home.

--Bill

Posted by: Ant103 Feb 28 2006, 06:04 PM

Winter will come around the month of May or April?
But, at the date of the passage from Autumn to Winter, the Sun will be at the nearest point to the horizon.
So Spirit need to run now if the engineer want to keep the rover in a good state of electric power, 'cause the Sun is now near of the south horizon.

Posted by: ToSeek Feb 28 2006, 06:21 PM

"Now run away before I taunt you a second time!"

Posted by: helvick Feb 28 2006, 07:02 PM

Southern Hemisphere mid winter on Mars happens on Spirit Sol 924 which is the 8th of August. The date of minimal insolation actually happens 11 or 12 sols earlier around Sol 912 (27 August).

The effects of mars orbital eccentricity and latitude mean that Opportunity's minimim insolation date is around a week earlier on Opportunity Sol 884\885 (20 August).

Posted by: Bob Shaw Feb 28 2006, 07:59 PM

"Let us leave Home Plate; it is a Silly Place!"

Bob 'Ni' Shaw

Posted by: elakdawalla Feb 28 2006, 08:08 PM

I heartily concur with the soundtrack choice!

--Emily

Posted by: AlexBlackwell Feb 28 2006, 08:24 PM

Yeah, Pink Floyd's music is well-suited to planetary exploration. As I recall, the Galileo team played some tracks from Dark Side of the Moon during the two Earth/Moon flybys.

And I once saw an animation of a Mars airplane concept with "Learning to Fly" played in the background. It was pretty cool.

Posted by: SigurRosFan Feb 28 2006, 08:39 PM

By Tom Petty, or?

Posted by: AlexBlackwell Feb 28 2006, 08:46 PM

Pink Floyd.

Posted by: imipak Feb 28 2006, 09:23 PM

Great images (and the new technique looks really nice!)

The voice in 'On The Run' says "live for today - no tomorrow!" which is a touch nihilistic for me (though the paranoid electronic throbbing is about right!) OTOH... 'Run' by New Order? "Well what's the use in complaining / When you've got what you don't need?" ...'cos I bet it's a bit more than 7x more disk space that's been filled with Mars images than would have been the case if the rover'd died when expected. I keep reminding myself to be grateful even when the Exploratorium is down.

Posted by: Nirgal Feb 28 2006, 11:37 PM

Micheal, your great panorama work is getting better and better !
I like your images especially for the more "dynamic look" of your projection techique
compared to the usual autostitch-look
And with your new vignetting reduction, it's even better ... great stuff

Posted by: odave Feb 28 2006, 11:46 PM

If we want to stick with Floyd, there's "Run Like Hell", but I wouldn't want to see Spirit sent back to Steve in a cardboard box.

How about Tom Petty's "Runnin' Down a Dream":

Posted by: ElkGroveDan Mar 1 2006, 12:01 AM

Actually a stanza from "Time" on Pink Floyd's "Dark Side of the Moon" would be appropriate here:

So you run and you run to catch up with the sun but it's sinking
Racing around to come up behind you again.
The sun is the same in a relative way but you're older,
Shorter of breath and one day closer to death.

Posted by: mhoward Mar 1 2006, 12:13 AM

Thanks Nirgal, imipak. It's nice to have some positive comments.

On second thought, I think Pink Floyd is too much of a downer for our intrepid rovers. Surely they will live forever, right? At least for a lot longer, I hope.

Posted by: Zeke4ther Mar 1 2006, 02:11 AM

I like it! Good choice!

Posted by: Tesheiner Mar 1 2006, 09:16 AM

This rover is driving really fast!
I'm still working on sol 766 images and the new pics after sol 767 drive are already available at the exploratorium.

http://nasa.exploratorium.edu/mars/spirit/navcam/2006-03-01/

Spirit seems to be currently at/near the NE corner.

(272k)

Posted by: Tesheiner Mar 1 2006, 09:56 AM

Sol 766 drive was a good one.
Here is a pancam mosaic (taken on sol 742) with the estimated positions on different sols.

<deleted image>

Now I'm trying to pinpoint today's position; help is welcome.

Edited: This is the estimated position, but I'm not really convinced.

(400k)

Posted by: Bill Harris Mar 1 2006, 01:32 PM

I agree with your assessment of Spirit's location: it has to be the NE corner of HP. And the drive was fast. I assumed that they took the route at the base of the scarp so that we could look at the lateral character of the HP Formation. I'm wondering, though, why they didn't stay on top of HP and make the drive so that we could image the bedrock "within" the bowl of HP. That would have taken an extra Sol, but it would have answered some questions (and posed more questions for later).

--Bill

Posted by: Burmese Mar 1 2006, 03:52 PM

I think they were afraid of crossing the top of HP and then not being able to find a way down, especially as any exit ramp on the south side would most likely angle Spirit away from the sun.

Posted by: tdemko Mar 1 2006, 06:24 PM

Maybe the JPL folks are reading our "backseat driver" posts!

This new locality is very interesting...it shows very clearly the boundary between the upper cross laminated unit and the underlying more poorly bedded unit.

http://qt.exploratorium.edu/mars/spirit/navcam/2006-03-01/2N194464218EFFAPA0P0685L0M1.JPG

This boundary was obscured by float and more recent aeolian material at Gibson. Here we can see that is indeed a very sharp boundary. Hopefully we will get a few close-ups, if not MI's of this surface. The poorly bedded, kind of "clotty" looking unit also is visible in vertical section here, rather than the oblique views we had at Gibson.

Posted by: jvandriel Mar 1 2006, 07:24 PM

Spirit is down from Home Plate and on its way to McCool Hill.

A 360 degree panoramic view taken on Sol 766 and Sol 767 with the L0 navcam.

jvandriel

Posted by: Bill Harris Mar 1 2006, 07:48 PM

It's easy to be an armchair quarterback; the eastern ramp off of Homeplate looked good from afar, as indeed it was, but they are properly playing it conservatively since power levels are waning and time is running out.

This underlying unit has been imaged much better than at Gibson, and even though we won't have time for a lenghthy stop, the Pancams will give us food for thought for the continuing adventure in the Spring.

I hope that they do listen to us here. After all, we are the best of the best of the best of the great unwashed off of Mt Ithaca...

--Bill

Posted by: Phil Stooke Mar 1 2006, 08:19 PM

Bill said: "After all, we are the best of the best of the best of the great unwashed off of Mt Ithaca..."


Oh good... I thought it was only me that didn't wash.

Phil

PS here's jvandriel's pan in a polar version:

Posted by: jvandriel Mar 1 2006, 08:21 PM

And a partial panorama of Home Plate taken later on Sol 767 with the L0 navcam.

jvandriel

Posted by: helvick Mar 1 2006, 08:30 PM

The http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20060301a.html puts Spirit on the approach to the north western corner of HP and explains that power considerations were the primary reason for this choice of route.

I'd love to get my hands on that model.

Posted by: neb Mar 1 2006, 09:02 PM

Note the broken chunks of fine grained basalt in the foreground of this panorama, Also some big pieces in the background that might be outcrops. Think there is a chance they might stop and look?

Posted by: mhoward Mar 1 2006, 09:06 PM

http://flickr.com/photo_zoom.gne?id=106421129&size=o http://flickr.com/photo_zoom.gne?id=106421131&size=o

Posted by: jvandriel Mar 1 2006, 09:15 PM

Here is the pancam L7 panoramic view.

Taken on Sol 766 and Sol 767.

jvandriel

Posted by: jvandriel Mar 1 2006, 09:41 PM

A panoramic view into the drive direction on Sol 767.

Taken with the L7 pancam.

jvandriel

Posted by: Steve Mar 2 2006, 01:28 AM

It's interesting that the dark formation on the slope of McCool hill (a dark outcrop of some kind surrounded by a dark shaded surface) is near the center of the drive direction panorama. Could the rover drivers have picked that as a target for investigation once they reach the hills?

Steve

Posted by: CosmicRocker Mar 2 2006, 05:37 AM

This is such an interesting place, and they have made it clear that 780 is the sol they do not want to linger beyond. I think we may yet have almost two weeks to study Home Plate. Also in the latest Planetary.org update, it was mentioned that they really do want to study the HP escarpment around the other side, to learn more about the layers. They could learn so much as they head for the hills that I can't imagine they'd simply try to make meters toward the hills. They are going to walk one side of this exposure and make observations along the way before running for the hills. I suspect they may leave before sol 780, just in case something else turns up that is worth more than a glance, but we should at least get to see what the rocks, contacts, and dips on the opposite side look like. At least, that's how I read it.

Posted by: sattrackpro Mar 2 2006, 12:06 PM

Thanks so much for that view! There are so many items I hope to see closer, but I'm wondering if we'll just see Spirit whisk on by most without much of a stop.

I've also began to wonder if the spot chosen to winter at might not be a surprise. Some think it must be far to the East in a more sun exposed area (green circle in attached) but, what of nearer options? Could not the "North facing slope" be somewhere along the nearer immediate South (yellow alternatives?) This would certainly provide a quick return to HP, and much closer trip to the "promised land."

The long-green-line certainly provides more interest to me, but what of travel time, there and back? What area provides the greatest chance of continued wind "cleaning" must also play a big part in where MER-B winters, I would think...

Posted by: djellison Mar 2 2006, 12:15 PM

I'm expecting the winter slopes to be almost exactly inbetween your green and yellow areas - just about where your blue line makes it's highest point. I don't think anyone's expecting them to go all the way over to that green area. Your yellow area is west facing, which doesnt offer any benefits.


Doug

Posted by: Phillip Mar 2 2006, 12:47 PM

An exciting aspect about the prospect of Spirit spending time on McCool Hill and then returning to Home Plate is that the scientific community will have an opportunity to thoroughly digest the information gathered during "Home Plate I," so that "Home Plate II" can be used to test the resulting theories. That process of field research on Mars, followed by extensive analysis and hypothesis formulation, followed by further field research at the same locale on Mars would itself be a "first" for Mars exploration.

Cross your fingers for dust devils and lots of sun for Spirit.

Phillip

Posted by: Tesheiner Mar 2 2006, 05:33 PM

Another move on sol 768.

Spirit is at/near the NE corner; images at the MER webpage.

http://marsrovers.jpl.nasa.gov/gallery/all/spirit_n768.html

Edited: Not a big drive. About 7m (parallax) heading in the direction of that far outcrop on McCool Hill.

Posted by: neb Mar 2 2006, 05:58 PM

Images pointed out by Tesheiner suggest Spirit has gradually climbed and is back on top of HP sequence??

neb

Posted by: Tesheiner Mar 2 2006, 08:45 PM

I think so.
Sol 766 & 767 moves were parallel to the northern edge but that edge (check the images) were gradually becoming smaller -- the terrain slope was higher than the top HP slope -- until tosol (768) drive, in which the rover moved again to the top.

Posted by: Bob Shaw Mar 2 2006, 08:58 PM

Some of that pavement is s-o-o-o like Meridiani...

Bob Shaw

Posted by: jvandriel Mar 2 2006, 09:41 PM

Spirit on its way to McCool Hill.

A 360 degree panoramic look taken on Sol 767 and Sol 768 with the L0 navcam.

jvandriel

Posted by: neb Mar 3 2006, 12:07 AM

In this panorama it appears the interval between the lower, discontnuous beds and the upper bedded unit is thinning toward the left. It seems that it may not extend beneath the flat upper beds in the background. Any comments??

neb




Bob: This kind of fracturing appears to be fairly common in exposed, flat-lying beds. It is even visible at a larger scale in some of the Mars orbiter images. Do you think think thermal activity (contraction- expansion could have anything to do with it??

neb

Posted by: RNeuhaus Mar 3 2006, 02:00 AM

I am surprised of the route which Spirit took. I tought that the best route would be to cross the center of Home Plate to study better about the bottom of bowl.

Analyzing the route, I think that the rovers are in very hurry and don't want to take any further risk to loose the time by crossing the center of HP and not be able to find a proper way out. The other speculation would be that the scientists would rather prefer to visit the north lateral of HP in order to study further about the formation of strata.

Now the Spirit is heading toward NE approaching to Mitchelltree Ridge. After crossing it, Spirit will be a volcanic valley heading to NE toward to Allegheny Ridge.

Rodolfo

Posted by: Phil Stooke Mar 3 2006, 02:50 AM

This is jvandriel's latest pan in polar form.

Phil

Posted by: Bob Shaw Mar 3 2006, 12:12 PM

Neb:

Well, there has to be *some* common(ish) process, and that would certainly be a planet-wide phenomenon. I don't remember seeing any numbers for temperatures at or just under the surface of Mars - you tend to see air temperatures quoted and figures for depths where water might exist, but not much inbetween. And I'm sure somebody will prove me wrong! Certainly, Lunar sub-surface temperatures are pretty static near the surface, barely seeing diurnal change - Mars, though? Maybe there's some THEMIS data out there...

Bob Shaw

Posted by: Bill Harris Mar 3 2006, 01:52 PM

I'd suspect that the diurnal thermal processes result more in exfoliation than the formation of the "paving slabs". This type of fracturing has a polygonal aspect and my first and continuing impression is that it is like mudcracks or frost polygons. There may not be a 1:1 analogue with these terrestrial processes, but the appearance is similar. Once a minute fracture forms, I'd suspect that the aeolian sandblasting over eons chips away at the fracture and significantly widens it.

OTOH, at Meridiani, I have noticed some apparent recent movement in the slabs so it lookss as though these are complex processes with many causes. Our Earthly experiences do not include rock that can lay on the surface for a billion years and be slowly weathered and eroded, so the timeframes are quite different.

I did a "google heatflow mars" and came up a lot of relevant topics to Bob's subsurface temperature question. A bit OT but still useful was http://www.mantleplumes.org/index.html .

--Bill

Posted by: Toma B Mar 3 2006, 02:58 PM

This is a surprise to me...take a look...
http://marsrovers.jpl.nasa.gov/spotlight/20060302.html

Posted by: SigurRosFan Mar 3 2006, 03:20 PM

Holy ...

Posted by: djellison Mar 3 2006, 03:29 PM

That's this winter's holiday trip sorted then....we're going climbing again

Actually - I wonder if they will go for the summit again, with the aim to roll to the top by next summer - would there be any benefit, or would it make more sense to head to different terrain.

Doug

Posted by: RNeuhaus Mar 3 2006, 03:35 PM

At the top of Mc Cool Hill would have a 23 meters higher than Husband Hill. Climbing during the winter until reaching the top would be very tough! I don't know if it is worth to effort to climb up to there again. Let see !

Rodolfo

Posted by: paxdan Mar 3 2006, 03:46 PM

They have to go for the summit.

as for it being higher, i'm actually several kinds of supprised nobody here spotted it first

Posted by: odave Mar 3 2006, 04:29 PM

I suppose the decision to get to McCool's summit might be driven by what comes out of the home plate analysis. If they do want to return to HP in the spring, would it be worth the time & effort for Spirit to top another peak? ISTR Steve saying that he and several team members are climbers, so there may be an emotional factor there too...

Posted by: Bob Shaw Mar 3 2006, 04:37 PM

Bill:

Interesting site!

Bob Shaw

Posted by: RNeuhaus Mar 3 2006, 05:21 PM

Now Spirit has stopped close to Mitcheltree Ridge and is currently spending three sols studying a rock target called "Fuzzy Smith" using three instruments on the robotic arm: the microscopic imager, Mössbauer spectrometer, and alpha particle X-ray spectrometer.

http://marsrovers.jpl.nasa.gov/gallery/all/2/f/769/2F194630651EDNAPBCP1131L0M1.JPG

During the coming week, Spirit will communicate with Earth in UHF-only mode while NASA's Mars Reconnaissance Orbiter arrives at the red planet.

Does anyone know about the speed (bit/sec) and reliability of UHF communication between MER and Earth (Stanford University Radatelescope in California). It will be much lower than 128 bps? It is probably that the transfer rate of image will be slowed down since UHF is much slower than the X-band communication which is perfomed by Odyssey and MGS. How long will last with this protocol of comunication, UHF?

Rodolfo

Posted by: Pertinax Mar 3 2006, 05:38 PM

I can't exactly say that I nailed it (I didn't trust my 'gut', my experience, enough), but I wondered about it: http://www.unmannedspaceflight.com/index.php?s=&showtopic=1301&view=findpost&p=17789

Higher or not it would be nice to view from the surface the south slopes of McCool Hill. I would question the value of doing so however with so many tasy things to explore in the inner basin yet.

-- Pertinax

Posted by: Deimos Mar 3 2006, 05:42 PM

I'm pretty sure the MER-Stanford communication is at best 1 bit. Not per second, just signal/no signal. Normally Spirit is commanded via X-band from Earth and downlinks via UHF through ODY; occasionally Spirit downlinks via X-band to Earth. Spirit will still talk to Odyssey via UHF, but the DSN stations aimed at Mars during the time Spirit would be commanded from Earth will be occupied by MRO. So, UHF only: uplink and downlink. That changes the timing of the uplink communication so as not to conflict with MRO (the Earth-ODY communications would have to occur when MRO doesn't need the DSN). So, Spirit will be in restricted sols (driving every other day at best) since there will be less time to write commands, but the data will continue to flow.

Posted by: centsworth_II Mar 3 2006, 05:51 PM

The rover drivers took a lot of time learning how to climb Husband Hill, also, a lot of time was spent examining new types of rock outcrop. They may surprise us with how quick McCool Hill can be climbed with a combination of previously learned climbing techniques and less time spent examining already seen rock types. If that's the goal.

Posted by: GregM Mar 3 2006, 06:14 PM

.

Posted by: centsworth_II Mar 3 2006, 06:24 PM

This assumes a decision not to return to Home Plate/Pitchers Mound in the spring. That may be a difficult decision to make.

Posted by: GregM Mar 3 2006, 06:48 PM

.

Posted by: odave Mar 3 2006, 07:24 PM

I'm inclined to agree with GregM - Spirit's remaining time is probably best spent getting the widest survey of her environs as possible. From the http://www.planetary.org/news/2006/0228_Mars_Exploration_Rovers_Update_Spirit.html, the leading HP hypothesis, that most of the team agrees with, is that it's an "eroded down volcanic construct", such as a tuff cone. Would evidence of the ground water that helped create the HP tuff cone, if that's what it is, still be accessable here? If not, a return to HP in the spring may not be necessary.

Posted by: jvandriel Mar 4 2006, 09:05 AM

A beautiful 360 degree panoramic overview of Home Plate and Husband Hill and McCool Hill.

Taken with the L0 navcam on Sol 768 and Sol 769.

jvandriel

Posted by: Phil Stooke Mar 4 2006, 02:29 PM

... and jvandriel's pan in polar form. The pattern of light and dark areas can be matched easily with the MOC view to locate the site on the route map.

Phil

Posted by: climber Mar 5 2006, 01:17 AM

In case you missed it, on MER's web site, the status as on march 3rd says :
"During the coming week, Spirit will communicate with Earth in UHF-only mode while NASA's Mars Reconnaissance Orbiter arrives at the red planet."
Does it means we'll have less data coming down for a while ?

Posted by: Reckless Mar 5 2006, 04:23 AM

Just a few colour pics from homeplate area Sol 770 this is what happens if I wake up at 4 in the morning.
Roy F Edit All are L457 and Tweaked.

Posted by: Bill Harris Mar 5 2006, 02:32 PM

This image shows the path that I think Spirit might follow over the Winter and next Spring. Spirit will start the trek to the north-facing slopes of McCool Hill and investigate the various outcrops-- layered and massive-- along the way. The impact crater near the summit may show a good section. Depending on time and what is seen on the way up, she may or may not look at the top of the hill. As Winter passes and insolation increases, she will make her way down the Western slope of McCool Hill. Depending on the need to do additional work at Homeplate and Pitchers mound, she will work her way Southward toward the chaotic terrain ("Promised Land"??) working the outcrop or she will stop by the "Ballfield" on the way to PL.

I am inclined to think that another visit to the "Ballfield" will happen since this is good exposure of a volcanic construct close at hand.

Again, thanks to Alan for his much-used color image of the Inner Basin.

--Bill

Posted by: centsworth_II Mar 5 2006, 03:57 PM

I hope they get to the top of McCool Hill. For the view, the geology, and, frankly, because it's there. I also think a return to Home Plate is in order. It's not even accurate to speak in terms of "return". The South and West sides of Home Plate have not even been seen, never mind visited. And Pitchers mound -- an even more intriguing feature than Home Plate in my view -- certainly deserves a closer look than the distant pancam shots taken so far.

Whatever they decide is fine with me though. To say I can't complain is a huge understatement.

Posted by: mhoward Mar 5 2006, 04:08 PM

I like this view toward Husband Hill, nicely composed with the rover tracks:

http://www.flickr.com/photo_zoom.gne?id=108151288&size=o

Posted by: alan Mar 6 2006, 01:38 AM

Spirit's getting ready to leave

772 p1941.03 0 0 0 0 0 0 home_plate_exit_5x1_3_bpp

Posted by: Tesheiner Mar 6 2006, 09:02 AM

Yup.

And talking of imaging sequences, I found the ones planned for tosol quite strange.

I believe not all of them will be ("were" by this time) executed, there is a lot of repeated shots, but I don't understand the reason for such disgregation.

Posted by: alan Mar 6 2006, 01:50 PM

I read that this week Spirit would need to send back data using its high gain antenna instead of the normal relay because MRO is arriving in Mars orbit. They may be breaking the sequences up so they can download the frames individually.

Posted by: Tesheiner Mar 6 2006, 02:29 PM

Spirit moved again on sol 772.
Some navcam pics available at the exploratorium and, based on their seq. ids, correspond to that "home_plate_exit_5x1_3_bpp" shot.

Mmmm, is really this the exit?

(122k)



Mmm, wasn't the communication restrictions a limitation to only use the UHF channel?
In that case, the constraints would be on the direct uplink of commands to the rovers, which would have to be made via Odyssey.

Now I'm puzzled.

Posted by: djellison Mar 6 2006, 02:40 PM

It's the other way around. UHF comms wouldnt get in the way of MRO - but DTE and DFE to the LGA or HGA have potential for cross talk with MRO.

The tracking site often mistakenly repeats sequence listings - the spacecraft can manage packatising the imagery itself, there's nothing specific required to do that.

Doug

Posted by: alan Mar 6 2006, 02:55 PM

OK that does make more sense.
I guess I should stick to maps.
http://www.unmannedspaceflight.com/index.php?s=&showtopic=44&view=findpost&p=44303

Posted by: Tesheiner Mar 6 2006, 03:00 PM

Now the whole set of pics is available. A much better view (Dilo's style)!

(392k)

Posted by: Bill Harris Mar 6 2006, 03:25 PM

Yep, that is a good panorama. I saw that Spirit was in the edge of the HP bowl and was looking around for a way to drive out. It looks as though she might drive to the right of the panorama (around the dark scoria outcrop) and then cut to the left and towards McCool Hill.

--Bill

Posted by: Tesheiner Mar 6 2006, 04:27 PM

Actually, the "drive-direction" pancam mosaic looks on that direction.
There are some dune fields which can be seen on the rightmost navcam image of my panorama; those ones are (I guess) on the same north-south corridor Spirit was from sols 714 to 735. Now it will be time to approach the corridor and go back northwards (then NE).

Posted by: mhoward Mar 6 2006, 05:40 PM

Wow.

http://www.flickr.com/photo_zoom.gne?id=108766432&context=photostream&size=l http://www.flickr.com/photo_zoom.gne?id=108766433&size=l&context=photostream http://www.flickr.com/photo_zoom.gne?id=108766434&size=l
http://www.flickr.com/photo_zoom.gne?id=108767392&size=l

Posted by: Bob Shaw Mar 6 2006, 06:01 PM

Great images, as ever - and Mitcheltree Ridge looks more and more interesting - that is if I'm seeing what I think I am!

Bob Shaw

Posted by: Phil Stooke Mar 6 2006, 07:26 PM

The new pancam mosaics also show great detail in the outcrops on McCool Hill, in the background. Clearly there will be lots to look at over there throughout the winter. And if a close inspection shows similarities to Home Plate, the need to come back will be greatly reduced.

Phil

Posted by: neb Mar 6 2006, 08:44 PM

M Howard's middle image on the left indicates the flat lying HP beds where the rover is sitting , show increasing dip toward the edge of the outcrop where the dip appears steeply toward us.

Also his upper right image shows beds dipping inward in a small circular depression. Any ideas??

Posted by: Oersted Mar 6 2006, 08:44 PM

What a dramatic ridge! - It is almost like a fortress wall with a bastion to the right.

Posted by: Bill Harris Mar 6 2006, 09:01 PM

Wow is right. This is what I think we're seeing: the prevailing/local wind direction is from the NW, so the "Gibson" side of HP is being eroded face-on to the section so it shows the layering quite well. The wind at this current exposure blows more parallel to the laminations so it shows the bedding surfaces better, although the view cuts across.

I'm thinking that the volcanic ash here did blanket this area and those wonderful outcrops on McCool Hill will be related and will show lateral changes. As Phil suggests, Spirit may gather enough data, as well as providing another image viewpoint, to reduce the necessity to return to HP, although the "cinder cone" at Pitchers Mound calls for a closer look.

--Bill

Posted by: Bob Shaw Mar 6 2006, 09:09 PM

Yes - Mitcheltree Ridge looked like not a lot until we saw these views, though it'd still be great to circumnavigate HP and have a look at Pitcher's Mound. Baby Mound, though, looks just like a mound - whatever is there seems well hidden. Anyway, the bottom line is that the structures we see locally may be part of an overall complex of exposures, and that's got to be good news.

Bob Shaw

Posted by: DFinfrock Mar 7 2006, 02:20 AM

For us non-geologist types... could someone give a best guess to what we are seeing on Mitcheltree Ridge? Is that an igneous dike? Or simply a harder more erosion-resistant layer? Or something else entirely?

David

Posted by: neb Mar 7 2006, 04:09 AM

David: Imo what you are seeing on Mitchelltree ridge are beds equivalent to those we are siiting on at HP.
The resistant layer is equivalent to the lower part of HP and is overlain by the lighter colored X-bedded layers. The unconsolidated material at the base is equivalent to the same material we saw at HP.

Posted by: CosmicRocker Mar 7 2006, 06:28 AM

Oh, man are there some things going on between where where Spirit now sits and across the gully to the next outcropping layers. The recent images of this side of the "plate" are astounding. I'm going to bite my tongue for the time being, because every time I look at them, I see something different. Oh, to be there in person.

Just why does the vesicular basalt float become abundant at this boundary? Was it extruded from dikes? Are the dips really changing? I don't think I was expecting this. The good news is that I think we are going in this direction and should get more useful information soon.

Posted by: Bob Shaw Mar 7 2006, 10:35 AM

Yup - and so far, nothing that shouts 'dyke', though originally I'd have thought that was a serious contender. But now we see the same structures elsewhere it mat mean that, strictly, we don't need to return to HP (though I'd still like to see Spirit drive right round, and have a good go at Pitcher's Mound too!).

(interesting typo there, now fixed, 'a good goat' - which seems to describe Spirit quite well!)

Bob Shaw

Posted by: edstrick Mar 7 2006, 11:02 AM

Considering what Sprit's made of, it'd be more likely to munch on old tin cans like a goat than on martian grass, if there were any.

I don't see any old tin cans, though... even if Richard Hoaxland and acolytes initially identified gobs of "artyfracts"

Posted by: Bill Harris Mar 7 2006, 12:17 PM

I've been sittting here fidgeting and waiting for the next image shipment to come in. If HP is an eroded maar, we are seeing details of the vent. I'm thinking that this change in lithology represents a change in the eruption. Earlier phases of the eruption produced the frothy vesicular "fractal spongebob" basalt which changed to the light-toned frothy "styrofoam-like" rock of the laminated "Gibson unit". I'll predict that we may see a transition between the two, and may also find rocks produced even earlier in the eruption.

Remember the things we saw on the headlong rush from Ultreya to here.

--Bill

Posted by: Tesheiner Mar 7 2006, 04:49 PM

773 p2380.15 32 0 0 32 2 66 pancam_home_plate_top_L257R1

FYI, there is a nice 4x2(?) L257 pancam mosaic being downlinked.

(170k)

Posted by: Oersted Mar 7 2006, 06:57 PM

Yeah, that would make one gasp.... and ears popping!

Posted by: mhoward Mar 7 2006, 08:34 PM

False-color:
http://flickr.com/photo_zoom.gne?id=109341835&size=l
http://flickr.com/photo_zoom.gne?id=109341836&size=l

Posted by: DFinfrock Mar 8 2006, 01:17 AM

I was unsure of what a maar was, so I did a little Google search. Check out: http://www.maar.us/

I'm sure that's not what Bill intended! But some of the other search results (including the USGS) were very helpful.

David

Posted by: Shaka Mar 8 2006, 01:35 AM

Coincidence....??

I'm staying with sandstone.

Posted by: mhoward Mar 8 2006, 04:18 AM

Nice Pancam false-color of "El Dorado" from here. Can't wait to see the mosaic tomorrow.

http://flickr.com/photo_zoom.gne?id=109497140&size=o

Posted by: Shaka Mar 8 2006, 05:35 AM

Hey, guy. I've heard of wish-fulfillment, but would even Ustrax want Lake Wobegon in place of Ultreya? I can't see the sailboats and waterskiers, but somehow I know they're there.
This colorizing business can go too far.
Seriously, the way Eldorado's albedo varies according to the viewpoint is not only amazing but a caution.

Posted by: jamescanvin Mar 8 2006, 05:40 AM

You don't need to...

http://www.physics.usyd.edu.au/~jcanvin/mer/index.html#A0773

Posted by: AndyG Mar 8 2006, 09:36 AM

Don't you mean fageting?

Andy

Posted by: algorimancer Mar 8 2006, 01:48 PM

That's the view I've been looking forward to seeing since we first looked down on home plate from above. Nice one

Posted by: Tesheiner Mar 8 2006, 02:02 PM

Beautiful, James!

I see an interesting/strange pattern at Ultreya/El Dorado dunes. Is that real or may it be a sort of jpeg artifact?

(Crop from http://www.physics.usyd.edu.au/~jcanvin/mer/index.html#A0773 full-res image)

Edited: I've edited the previous crop and added some drawing. I hope you don't mind, James.

Posted by: djellison Mar 8 2006, 02:19 PM

No - that's real - we saw the same 'ripple' pattern up close some time ago

http://pancam.astro.cornell.edu/pancam_instrument/el_dorado.html

Doug

Posted by: Tesheiner Mar 8 2006, 02:29 PM

Could be, but it's not the same effect seen from quite far away.
See that zig-zagging -- I've edited the previous crop and added some drawing.

Posted by: Tesheiner Mar 8 2006, 02:46 PM

Spirit moved again on sol 744.

(264k)
(Current navcam mosaic)

And it's position, as seen from sol 742 navcam mosaic.

(159k)

Goodbye Home Plate! See you again next spring.

Posted by: mhoward Mar 8 2006, 03:27 PM

I did anyway, but it was worth the (self-enforced) wait.

I can't add much to that, but here you can see the extent of Husband Hill:

http://flickr.com/photo_zoom.gne?id=109669795&size=l http://flickr.com/photo_zoom.gne?id=109669793&context=photostream&size=l

Posted by: alan Mar 8 2006, 04:01 PM

Check out the seam that leads to Oberth ( name is from JPL's latest route map )
http://qt.exploratorium.edu/mars/spirit/pancam/2006-03-08/2P195078715EFFAPFIP2382R1M1.JPG

Posted by: mhoward Mar 8 2006, 06:43 PM

Looks like the investigation is just beginning.

http://flickr.com/photo_zoom.gne?id=109736334&size=l

Posted by: jamescanvin Mar 8 2006, 10:21 PM

No problem, the more use my pictures get the better.





I'm pretty sure thats the real structure of the dunes/ripples. Attached is a .png of the raw .jpgs in that region with just contrast/brightness adjustment. Those markings are in all the filters and look like real dunes/ripples to me.



P.S. This is about it from me for the next 2.5 weeks. I look forward to seeing MRO safely in orbit, Spirit well on the way to McCool and Oppy the best part of a km closer to Victoria with a good view of it, when I return. I trust you lot can ensure that for me!

Bye,

James

Posted by: Phil Stooke Mar 9 2006, 12:02 AM

Consider it done.

Phil

Posted by: sattrackpro Mar 9 2006, 04:54 AM

Thanks Tesh, for the news! We've indeed left HP, and are heading straight for the next most interesting outcrop on the hill that Spirit will spend the winter on. That's a great picture!

We may not spend a lot of time at these places, but as fast as Spirit has been moving, it appears we have more than a month left before we reach the most ideal wintering place NASA might choose. I'm hoping this means we have time for thorough examinations enroute - before we 'park it' - so to speak.


You'll be missed, James... but, we'll do our best to leave a good diary here for you to read when you can get back.

Posted by: jvandriel Mar 9 2006, 10:26 AM

Here is the black and white one.

Spirit looking back.

Taken on Sol 773 with the L7 pancam.

jvandriel

Posted by: vikingmars Mar 9 2006, 11:02 AM

Now my gess for the route is :
1) to Korolev and Faget ;
2) spend the winter on the hills ;
3) go back to Home Plate (if needed after Korolev and Faget results) after the winter ;
4) and/or sample Von Braun ;
5) go south-east to Promised Land and follow as much as Spirit can the channel to its entrance into Gusev...
Lots of more nice pictures to come !

Posted by: Tesheiner Mar 9 2006, 01:44 PM

IIRC, Oberth, Korolev, and Faget are all on the western slope. Given the time constraints to be at a northern slope, my guess is that the study of those outcrops will be limited to the pancam & mini-tes.

Posted by: sattrackpro Mar 9 2006, 02:19 PM

Here's a quicky of the 4 frame 774 pancam

Posted by: Bill Harris Mar 9 2006, 06:34 PM

Here is a zoomed-in view of the Oberth outcrop/rubble-pile from a Sol 774 L7 Pamcam. This shows a blocky dark basalt with a thin "airfall" deposit around it. We probably won't look closely at it now, but it appears to be the same material as two other outcrops, Korolev and Faget, which are on the way to the North Slope.

--Bill

Posted by: Astro0 Mar 10 2006, 04:19 AM

Did anyone else think 'the 2001 Monolith' when they saw this on http://flickr.com/photos/36868531@N00/109736335/?

Considering the way the Rover mission has been going I wouldn't be surprised at all!

Hey, there's a thought for a very special SFX image!!
Astro0

Posted by: edstrick Mar 10 2006, 05:54 AM

Maybe about 6 MER rovers and a couple "baby" Sojourner types around a monolity, one close up to it with the robotic arm up on the side of the monolith?

Posted by: dilo Mar 10 2006, 06:48 AM

...and then, finally, we will make a mission to Europa (or Enceladus ) in search form alien lifeforms!
(hey, this is a pocket monolith!)

Posted by: Tesheiner Mar 10 2006, 10:50 AM

It's sized for "little green man".

Posted by: jvandriel Mar 10 2006, 12:45 PM

Again,

a great 360 degree panoramic view of Home Plate and McCool Hill and Husband Hill.

Taken with the L0 navcam on Sol 772 and Sol 773.

As soon as all the data is down, I will make a new one.

jvandriel

Posted by: Tesheiner Mar 10 2006, 12:53 PM

Tosol (776) planning includes driving and a 120º pancam of McCool for long baseline stereo.

Posted by: jvandriel Mar 10 2006, 01:23 PM

The passage to McCool Hill.

Taken on Sol 774 with the R0 navcam.

jvandriel

Posted by: Tesheiner Mar 10 2006, 03:30 PM

A quite short drive tosol (766); "just" 9m southwards.

Posted by: Shaka Mar 10 2006, 07:20 PM

Who's got a recording of the cadenza from Also Sprach Zarathustra played on the kazoo and piccolo? (No kettledrums, please, they give me a headache.)

Posted by: jvandriel Mar 11 2006, 02:18 PM

Spirit looking back at the wheeltracks after driving of Home Plate.

Panorama taken on Sol 774 with the L7 pancam.

jvandriel

Posted by: jvandriel Mar 11 2006, 09:43 PM

McCool Hill.

Panorama taken on Sol 776 with the L2 pancam.

jvandriel

Posted by: edstrick Mar 12 2006, 01:10 PM

This may be the same pan... bands 2 and 7 only.

Posted by: Bill Harris Mar 12 2006, 01:38 PM

It is going to be interesting to see what the story behind Oberth, Korolev and Faget is. I had hoped that a visit to Korolev and Faget would tell the entire story, but it seems that these two outcrops are stratigraphically higher than Oberth, so a visit to Oberth next Spring may be in order. All three seem to be blocky, deeply weathered and oxidized and likely related.

--Bill

Posted by: Steve Mar 12 2006, 02:56 PM

Wow

Looking at Oberth in the center of this picture what are we to make of those two shadowed dark circular features? Are they some kind of vents with dark deposits from some kind of emissions (dusts, deposits from vapors or even fluids) on the downslope?

Posted by: algorimancer Mar 12 2006, 03:04 PM

Really gives a sense that the Home Plate unit continues into the hills. Nifty layering

Posted by: Bill Harris Mar 12 2006, 04:28 PM

This is going to sound a bit off the wall, but this is what Oberth has always impressed me as being...

--Bill

Posted by: alan Mar 12 2006, 04:59 PM

Anaglyph of 776 panorama

Posted by: jvandriel Mar 12 2006, 08:25 PM

The last data is down and here is the complete 360 degree panoramic view of Home Plate, Husband Hill and

McCool Hill.

Taken with the L0 navcam on Sol 772, Sol 773 and Sol 774.

jvandriel

Posted by: jvandriel Mar 12 2006, 08:51 PM

Spirit on its way to the passage and to McCool Hill.

A 360 degree panoramic view taken with the L0 navcam on Sol 774 and Sol 775 after leaving Home Plate.

jvandriel

Posted by: CosmicRocker Mar 13 2006, 06:21 AM

That was such a spectacular cross-sectional view of of the wind-driven sand ripples of the upper part of Home Plate that I am compelled to post a false color version of it from the sol 774 L257 pancams, composited by MMB and assembled by Autostitch. The first face we saw of Home Plate was fairly spectacular with its grotesque erosional features, but this slice through the plate will be the one I remember. This image could have been recorded from any number of places in Arizona, Utah, or New Mexico, not to mention many other countries on our planet.


Just a few days ago I thought I had convinced myself that as the dips rolled over as we left HP, a part, if not all of the section was missing. More recent imagery seems to show Spirit driving on a weathered, "popcorn" textured surface reminiscent of the lower beds of HP. The most recent images are even showing the upper, cross-bedded section, it appears. Why are they spending so much time here, and barely moving? They must be closely looking at something.

Posted by: Bill Harris Mar 13 2006, 11:15 AM

There have been a few spectacular panoramas lately. My favorite is the stretched pam by Dilo that clearly shows the bowl-like aspect of HP.

But, as Tom asks, why are we lingering here so long? Last I heard a week or two back was that Spirit had to, had to , had to get moving to a north-facing slope because of the power situation?

--Bill

Posted by: djellison Mar 13 2006, 01:18 PM

Spirit's currently on UHF only due to the MRO/MERA DSN channel clash. I'm sure this will be worked around in due course, but the latest JPL update does mention it....

During the week, NASA's Odyssey spacecraft has been relaying commands from Earth to Spirit via the UHF link. Communications over X-band frequencies have been allocated for use by the Deep Space Network to track the Mars Reconnaissance Orbiter during its approach to the red planet. Next week, Spirit is expected to resume operations via X-band uplinks.

Commanding via UHF has a longer lead time, as uplinks to Odyssey are not a daily event.

Doug

(PS - at 360 whrs in a sol, it may be that serious activities such as driving etc are limited not just by comms, but also by power. A few days to ensure some very fully charged batteries will be good given that there may be some unforseen unfavorable tilt on the way to McCool)

Posted by: Phil Stooke Mar 13 2006, 04:09 PM

A couple of recent polar views, adapted from the panoramas posted by jvandriel. We get a good view of the 'dugout' between Home Plate and Mitcheltree Ridge.

Phil

Sols 772-774:

Sols 774-775:

Posted by: Tesheiner Mar 13 2006, 05:17 PM

Sol 779 post-drive navcam images are available at the exploratorium.
http://nasa.exploratorium.edu/mars/spirit/navcam/2006-03-13/

Spirit seems to have moved about 30m (parallax measurements) towards Oberth.

Posted by: sattrackpro Mar 16 2006, 05:40 AM

It looks like immediately beyond Oberth may be one of the best North facing slopes nearest to Spirit. If the latest power numbers are correct, MER-A is operating on somewhat low power now, and without doubt the wheel problem helps (to a degree) make that problem worse.

If I don't miss my bet - I'd think they will act to get to any kind of nearby slope that tips the PP surface of Spirit Northward, and get the power level up before going much of any place else - while they fully assess the situation.

At this point I doubt we'll see much of any effort to climb too far up McCool - anywhere - in the next few days, and possibly through the winter, if they find the terrain above and behind Oberth satisfactory.

Posted by: sattrackpro Mar 16 2006, 06:00 AM

Spirit is at (about) the red square in the attached - with three almost equidistant slope choices nearby - but only one, behind Oberth, seems to offer the brighter green (better) sunny slopes. But, the best spot has to be climbed up to.

The other two spots are of a less bright green, and both look limited in suitability by comparison. But condition of the wheel will make the choices less clear though, as climbing will limit them.

Posted by: Shaka Mar 16 2006, 06:05 AM

Sorry, Sat, I can't agree. I'm not ready to immure Spirit in that 'cemetary plot' forever or even for seven months . She dragged herself several meters yesterday and had enough power to do it. I say it's worth the risk of losing her to haul ass and bad leg as fast as we can to a hero's zone where she can 'limp' out her remaining weeks or months continuing her epic exploration of Mars. I can't accept that the very SPIRIT of this Mission might end in a whimper.

Posted by: sattrackpro Mar 16 2006, 06:21 AM

Nor do I.

Posted by: djellison Mar 16 2006, 08:30 AM

Well - chances are the rovers will both die in a whimper type fashion - slowly and painfully.

Doug

Posted by: Tman Mar 16 2006, 08:52 AM

Maybe we should see it like a human grow older. Anything is going slower and wiser and one can look back on a fulfilled life

But it isn't especially funny...

Posted by: sattrackpro Mar 16 2006, 09:36 AM

True, but hopefully not any time very soon... however, Sol 800 is near. Twenty days to reach safe haven - and they have a dead wheel to contend with. Somehow, I believe they will make-do - and the drama of the MER saga will continue to amaze.

Posted by: Tesheiner Mar 16 2006, 10:03 AM

I did some parallax calculations to estimate the last movement.
About 2.2m headed towards a point left of Oberth's line of sight; a very short drive.

(81k)
(Pre-drive navcam)

(77k)
(Post-drive navcam)

Let's hope tosol movement (yes, another drive is planned for sol 782) is better.

Posted by: Analyst Mar 16 2006, 10:25 AM

Some people here seem to think Spirit MUST reach the northern slopes of the hill to survive the winter. This is simply not true.

Spirit needs A northern slope to do any useful work, and maybe to survive the worst days in winter. BUT it doesn't have to be McCool hill. Any northern slope works for suvival, even the rim of a 3m crater or the rim of Homeplate. It may be desireble to reach McCool hill because you can drive there even in winter and study different places, it's not only a small local norhern slope there you have to stay. But to do useful work again in spring you don't have to be at McCool from an engineering point of view. To say we run for our lives is simply wrong. I'm sure there is a local northern slope within 25m (If you consider this a run, o.k. )

Analyst

Btw., the sol 800 deadline is a little flexible by itself (and not a DEADline).

Posted by: djellison Mar 16 2006, 10:27 AM

But do you want to spend 300 odd sols parked in one spot?

Doug

Posted by: Analyst Mar 16 2006, 10:44 AM

I didn't say this; and if it's a spot at Homeplate why not? I'm only speaking against this "run to McCool or die (by sol 800)" attitude some people have.

Analyst

Btw., we didn't drive much the last winter and did useful work at West Spur. And we missed lot's of local spots there because the slope was bad 2m away from our position.

Posted by: djellison Mar 16 2006, 11:02 AM

Depending on how you define winter, we drove all the way from West Spur to the Wishstone area, several hundred metres in all.

The choice is - spend a few days getting the McCool where there will be several hundred metres of hill to explore during the winter, or park near a small local slope where there will be a few metres to explore and leaving that risks killing the rover.

The effort to get to McCool hill is very very worth while. If things get worse than they are now, there are parts of McCool that will offer some really good slopes to get the very best power we can.

Also - if you're doing mobility analysis on that FR wheel - doing it on the slopes of a hill where you have dozens and dozens of metres of driving available to you whilst maintaining a good slope is a viable option. Doing it on the edge of Home Plate isnt.

Getting up onto that Hill has the potential for stronger winds ( as we saw at Larry's Lookout ) and thus more cleaning events - something we've not seen since hitting the south side of Husband Hill 200 sols ago. Being higher up means that UHF passes will probably be a little cleaner and longer. There are lots and lots of reasons to get to McCool hill. Other than 'it's a bit closer' - I can see no reason to use some of the poorer, restrictive local slopes.

Doug

Posted by: sattrackpro Mar 16 2006, 11:03 AM

I don't believe anyone here holds that impression at all.

Steve Squyers has said they want to be in safe territory by Sol 800 - he didn't say that the rover would die if it were not - and I think everyone understands that NASA at least tries to work within a margin of safety when they set published goals.

Posted by: Ames Mar 16 2006, 11:07 AM

I think the problem with locally favourable slopes are that there are lots of less than favourable slopes all around. If a drive was prematurely terminated for some reason(!), and the rover happened to stop on one of these bad slopes then that could be IT! - Gonner!
It is a risk that is much reduced by sticking to a larger area northern slope.

I am also sure that there will be a lot of good stuff to do on McCool - On Mars, surprise is just around the corner (or just up there a bit!).

Nick

Posted by: djellison Mar 16 2006, 11:11 AM

Consider a winter on McCool's Northern slopes - we could trundle along to the eastern edge - image the far Eastern Basin, then trundle back again ready to return to HP or other targets next spring. It's very very worth while getting there in my opinion.

Doug

Posted by: sattrackpro Mar 16 2006, 11:30 AM

And I hope they do too! I'd very much like to see that 'Eastern Basin' - and sure many others would too.

Here's an interesting old topo map from OSU (2003) that we can tell isn't exactly accurate (from what we have seen) but it illustrates West Spur, and that Northern side of McCool that many think the best place to be is... in that blue circle somewhere.

Other possible sites (red circles) don't have the interest level, though they were considered 'safe' in the prior image from GSI, but they would certainly limit movement. It'll be very interesting to see which way we go...

Posted by: Tesheiner Mar 16 2006, 11:52 AM

Another interesting (imo) target would be those "dark stripes" indicated by climber in http://www.unmannedspaceflight.com/index.php?showtopic=2246.

Posted by: antoniseb Mar 16 2006, 12:07 PM

I don't recall whether the dust devils are seasonal or not, but it strikes me that we'd like to try and place Spirit where the wind will be likely to clean dust off. I got the impression that during the trip down to Home Plate, we were in a high dust accumulation zone.

Can someone who actually knows about this fill me in please?

Posted by: Analyst Mar 16 2006, 12:30 PM

From your first quote I did. And there were similar postings by others. But of course it can be only me.

I never said I McCool is not desireble. Sometimes I doubt someone really read my posting.

Last thought: I strongly doubt Spirit will die after an terminated drive ending on a bad slope, yes, even in winter. The batteries can compensate for one or two bad days with say 250 whr. Surely you have to recover fast, probably the next two days, and yes it is risky. The slope one McCool can avoid this risk to some degree, but not completely. There may be local bad slopes too.

Analyst

Posted by: sattrackpro Mar 16 2006, 12:37 PM

That's a most interesting thread, Tesh... - particularly the image posted by SigurRosFan http://www.unmannedspaceflight.com/index.php?s=&showtopic=2246&view=findpost&p=41544 which seems to indicate a possible fairly quick arrival in Doug's most green area. But, image compression plays tricks, too.

Looks like a 3 or 4 day six-wheel drive... perhaps 6 to 9 days, 5-wheeling it, but it may be several more. Doug thinks it possible - hopefully so do the drivers.

Posted by: djellison Mar 16 2006, 12:47 PM

Dust Devils are seasonal - but remember, there is not evidence that an actual DD has ever cleaned Spirit - it's just good strong winds that have done that. Of course, stronger winds occur when there is more energy around, triggered by more sun, which happens during the summer. However - hill sides will always offer stronger winds that the inner basin.

Doug

Posted by: Bill Harris Mar 16 2006, 01:40 PM

And also, these "thermal winds" are caused by the temperature difference between the warmer air at the sun-heated surface and the cooler air a few meters aloft, so during the winter there is also great potential for thermals on the north-facing slopes.

She'll survive; our intrepid explorers are plucky.

--Bill

Posted by: Shaka Mar 16 2006, 09:34 PM

G'Day, everybody!
Just to clarify a point regarding my view on Spirit's future, and its possible mis-analysis:
Run to McCool, or it might as well be dead.
Yes, Spirit has as much chance, or more, of surviving the winter perched on the north slope of Home Plate, but it hasn't got another 300 sols worth of science to do there. We may already know 85% of what Spirit could ever learn about that area. The area of Home Plate we could safely occupy over the winter is perhaps 80 to 100 square meters, the area on McCool is orders of magnitude larger, and we know close to zero percent about it now.
There may be nice northerly facing slopes high up above Oberth, but if you try to climb a westerly facing slope to get there, you will fail. We apparently are operating close to our insolation minimums now, and getting lower day by day. Tilt the solar panels west and we will drop below minimums long before you can climb McCool. There Spirit will die with a whimper.
The north face of McCool puts us in as safe a winter location as could be found anywhere in the Columbia Hills, it offers us as much new science to do over the nest 300 sols, as Spirit could hope to accomplish even with six good wheels. It is a major pass through the Hills, and will probably have enhanced wind velocities as soon as we get there to clean our panels. It offers a steady climb with new science along the way and finally, next spring a view to the east and south that may reveal hitherto unknown wonders.
Run to McCool.
Shaka

Posted by: alan Mar 16 2006, 10:30 PM

Maybe we should rename this thread "Limp to McCool"

Posted by: Shaka Mar 16 2006, 10:44 PM

"Drag to McCool"
It's cooler.

Posted by: Gonzz Mar 17 2006, 12:39 AM

Important item for any future rovers's that rely on solar power:

Tilltable solar panels!

Posted by: Marz Mar 17 2006, 02:44 AM

And maybe a dust-mop attachment for the arm?

Seriously, with the success these rovers had in surviving so long, I'm sure the next solar-powered rovers will have some consideration into ensuring their longevity.

Posted by: ElkGroveDan Mar 17 2006, 02:50 AM

Let's include retractable wheels on our wish list.

Posted by: Shaka Mar 17 2006, 03:00 AM

Meanwhile Spirit drags on regardless:
I would like to introduce a new geological term: a Popcorn Mesa http://qt.exploratorium.edu/mars/spirit/navcam/2006-03-16/2N195788011EFFAQ67P0665R0M1.JPG
Looks like pretty good progress for a 'cripple', and what's that patch of white our hero has already turned up with his 'pegleg'? http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2006-03-16/2F195787603EFFAQ67P1211L0M1.JPG
Let's get this 5-legged show on the road!
http://marsrovers.jpl.nasa.gov/mission/status.html
Our beloved managers think so too!

Posted by: Tesheiner Mar 17 2006, 09:44 AM

I double-checked my numbers and did the measurements again with both algorimancer's and jmknapp's parallax calculators and the result is again net distance=~2m.
Maybe that 4m figure was the planned manouver or distance measured by wheel turns (without taking slippage into account)?



Spirit moved again on sol 782. This time the covered net distance was about 8-9m, based on parallax calculations.

Posted by: kungpostyle Mar 17 2006, 02:15 PM

I think the Rovers would look great with a spare tire on the back like a Jeep!

Posted by: mars_armer Mar 17 2006, 02:20 PM

I think they drove forward first, then backward, so the net distance was less than the total drive distance.

Posted by: Burmese Mar 17 2006, 02:23 PM

Yeah, they are determinedly dragging the bum wheel along. Getting a good view of the bedrock just under the surface power, though.

http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2006-03-16/2F195787603EFFAQ67P1211L0M1.JPG

Hope they can do better that 10 meters a day that way.

Posted by: ljk4-1 Mar 17 2006, 07:31 PM

Spaceflight:

* Spirit Mars Rover In 'Drive Or Die' Situation

http://www.space.com/missionlaunches/060317_spirit_update.html

NASA's Spirit Mars rover has wrapped up exploration of a baffling feature called
"Home Plate" but now faces the onset of martian winter while dealing with
dropping power levels and fighting a balky right front wheel.

Posted by: Marcel Mar 17 2006, 08:13 PM

The problem of a moving part is that it can stop moving. Just like a wheel. Or a joint in an arm. It's not robust. The more mechenical systems are introduced, the smaller the chance of operating without failure for long timespans. It's better to install larger panels (that provide more energy as an intrinsic property of the system), than smaller moveable ones (that can fail in keeping track of the sun).

I think the sweeper on an arm isn't an option too: they surely thought about that before. There's been a thread about this long ago on UMSF: there simply was no extra weight budget left. Every gram of these vehicles is thought trough. Wipers, removeabel foil, canisters with compressed gas to blow them clean...i'm sure these options have passed all the smart minds several times. Besides: it would have been too complex to integrate (one of these) options in an rover that made it's interplanetary trip folded up like an elephant in a matchbox.

I think the best two options are
1 RTG's
2 Solar panels that somehow make use of electic repulsion forces that prevent the dust from settling down.

Posted by: helvick Mar 17 2006, 08:23 PM

3 More efficient panels. The state of the art is now almost 50% more efficient than the panels on the two MER's and a further 15-20% is within reach over the next 4 years or so.

Posted by: Shaka Mar 17 2006, 09:39 PM

Yes, and I have little doubt that they will soon be sturdy and flexible enough to cover the entire outside of a rover like a coat of paint. Still the RTG in MSL will relieve us of a lot of fretting about the supply of power - day - night, winter - summer, sunlight - shade, north-facing - south-facing, duststorm - clear, - it's all the same. If we're going to get down and dirty in the channels and ravines of this dusty planet looking for the signs of life, we've got to get away from dependence on solar power. It's fantastic in space, but too unreliable for exploring Mars.

P.S. Erin go Bragh

Posted by: djellison Mar 17 2006, 10:37 PM

But with solar panels - you can still get unlucky - a bad dust storm and you're done. Good night. So long. You don't know if you'll have 1000 Whr's in a months time, or 300. You can't plan long term.

RTG's are the only sensible power platform currently available for long term surface exploration. You know exactly what power you're going to have, every single day, for the next 10 years.

Doug

Posted by: helvick Mar 17 2006, 11:25 PM

That's true for a rover and is absolutely true for MSL in particular but the improvements in photovoltaic power are not to be sniffed at.

A fully cladded MER (and I mean the same chasis and wing layout but pretty much fully covered on all major surfaces including those on the underside) with current cell efficiencies would have about 4m^2 of cells running at 40% efficiency (assuming we had them).

Peak power under good optical conditions would only be around double the current design since most of the surfaces will be shaded or at a poor angle most of the time.

The interesting thing though is that in a really bad storm even though total surface insolation drops the diffuse insolation rises. At mega storm level (Tau=5) the insolation drops to 20% but since its virtually all diffuse all of the cells will be generating and the net output would sill be 25% higher than the normal peak output of the current MER's. And most of that (70%) would be from cells that are pretty much immune to dust losses.

Additionally the penalty for poor orientation would not be as severe since some surface would always be in an improved orientation. It wouldn't be totally foolproof but it would drop the orientation penalty from around 30% to around 10%.

One other advantage of this is that it makes the Northern Hemisphere more accessible (since the higher Tau season corresponds with local winter).

Posted by: Shaka Mar 18 2006, 03:02 AM

T' be sure, t' be sure, but in a really bad storm y'll also be needin' a leprechaun with a broom constantly sweepin' the top, or the weight of dust buildup will push ye into the dear old sod. 'Tis the Lord's truth.

Posted by: edstrick Mar 18 2006, 12:30 PM

4 frame color pan (a big "jpeggy") of outcrops near HomePlate, and a single frame of "popcorn"

That stuff reminds me of pot-of-gold, way back when, or some popcorny textured sulfate rock at the lowest levels reached in Endeavour crater.

Posted by: Steve Mar 18 2006, 02:41 PM

http://qt.exploratorium.edu/mars/spirit/pancam/2006-03-17/2P195873859EFFAQ67P2391L7M1.JPG suggest another alternative that the dark deposits on the downslope may be aeolian deposits forming in sheltered areas. As we drag our way toward Oberth (and vicinity) time will tell.

If these do mark areas where dust is deposited, they might be places to avoid to keep the solar cells going.

Posted by: Shaka Mar 18 2006, 09:37 PM

Actually, my interpretation of the most recent rear hazcams indicate we are heading more or less directly toward Korolev and Faget: http://qt.exploratorium.edu/mars/spirit/rear_hazcam/2006-03-18/2R195964770EFFAQ75P1311L0M1.JPG
This is the correct direction to reach the North Slope ASAP. Oberth is just out of the frame to the right.

Posted by: sattrackpro Mar 21 2006, 04:09 AM

Well, this is most interesting...

MarsDaily.com has a new article up (dated today) that has Steve Squyres saying that Spirit does not have to get to a north-facing slope to survive, but has to in order "to keep doing science." You can read the article http://www.marsdaily.com/reports/Squyres_Getting_A_Handle_On_Home_Plate.html

Posted by: sattrackpro Mar 21 2006, 05:45 AM

I have some friends that work at JPL in Pasadena - and am running the following thinking by them.

The speculation at NASA is that the motor brushes (one, or more, or all) ‘lost contact’ – causing the inoperative front wheel. That's certainly possible, but seems less likely, for a number of reasons that I won’t discuss here, than another cause.

That possibility is - we are seeing the result of another broken wire. The robotic arm on MER-B stopped working, NASA believes, due to a broken wire. Both that wire, and the wiring to the wheel on MER-A, must flex in a limited amount of space, and must do so repeatedly under very cold conditions – under which most metal-content conductors will suffer fracture-failure sooner or later.

Of course, I have near zero knowledge of the materials used to construct the conductor that provides power to the motor, nor how much stress is placed on the conductor via flexing. But, given that the motor stopped shortly after turning the wheels to line-up for satellite communication, I’m of the opinion that a conductor just reached the end of its ability to endure repeated flexing.

I don’t know for certain if they can raise or lower the amount of D/C power fed to the wheels, but I’m led to believe that they can. If they can, and if they can stop the power feed to all five working wheels, and raise to max, the current to the non-working wheel for measured milliseconds at a time – they may be able to restore the wheel to powered service, under very limited terms.

It is possible to ‘fuse’ some conductors back together, as I have done many times – but the bond is usually extremely weak, and normally would not suffer much flexing of any kind. However, I’ve seen such ‘emergency arc-bonds’ last a very surprising long time under difficult circumstances.

Tests being conducted at JPL will tell the real story soon enough. But, I think we can guess one part of it – flex-joint wiring is often very difficult to design, build and guarantee, particularly on Mars, beyond limited terms. That 90 day limit was set, to a large extent, for this and other relevant reasons.

Posted by: Cugel Mar 21 2006, 08:51 AM

A broken wire makes more sense to me than the brushes losing contact because in the latter case you expect to see some gradual performance degradation. (But maybe we just don't know...) Unfortunately, it doesn't really matter, does it? If one wire breaks because of wear and tear, how much longer will the remaining and identical components last? I believe it is extremely unlikely that spirit will survive another winter.

Posted by: tty Mar 21 2006, 12:43 PM

The good news in this case is that it was the wheel that had been drawing more power and had therefore been through more severe thermic cycling than the others that broke. Similarly it was Opportunity's arm joint with the stuck heater, and therefore also a more severe thermic environment, that failed first suggesting that in both cases the other unit(s) probably have some life left, though we are probably getting close to some irrecoverable failure.

tty

Posted by: atomoid Mar 21 2006, 10:18 PM

I'd always thought this was the source of the salt pockets that the rover wheels keep churning up, which would result from blown-in accumulations of dusts of this easily-eroded popcorn stuff buried under other types of dust with the changing wind patterns. Now we see a huge popcorn bank here, there should be deep salt pockets all around if this were true. did we get spectra of this or other popcorn to compare it with the salt pockets?

Posted by: Oersted Mar 21 2006, 10:49 PM

That's good thinking!

Posted by: Shaka Mar 21 2006, 11:03 PM

http://qt.exploratorium.edu/mars/spirit/navcam/2006-03-21/2N196232393EFFAQAEP1908L0M1.JPG
Looks like a certainty. Popcorn=iron sulfate salt aggregates.

Posted by: mhoward Mar 22 2006, 01:56 AM

Sol 787, looking down:

http://flickr.com/photo_zoom.gne?id=116116170&size=l

Posted by: RNeuhaus Mar 22 2006, 02:25 AM

Squyres mentioned that solar panels are dirty and he didn't mention that any other places would guarantee to have good winds speeds and amount to clean Spirit's solar panels. He is just thinking of a proper a north-facing tilt. Maybe he has missed to stress it to the press.

Rodolfo

Posted by: edstrick Mar 22 2006, 06:55 AM

The more I see interesting stuff *CHURNED* up by the rovers wheels, the more frustrated I am that there's no very simple plow or trenching tool on board.

Then, as always, I ask myself what would that have had to leave off the rover I'd miss just as bad.

Posted by: djellison Mar 22 2006, 08:35 AM

Well - both rovers have done a fair bit of trenching already

Doug

Posted by: Oersted Mar 22 2006, 08:39 AM

North-facing tilt is something you can go out and look for, wind cleaning is down to chance, even though you can try to go to places that look promising.

Posted by: edstrick Mar 22 2006, 11:33 AM

Using bands 2, 5, and 7, a closeup of the salts in the track (with a strong contrast stretch) show interesting color differences.

Posted by: Bill Harris Mar 22 2006, 01:59 PM

Me too; but as you say, these rovers are the prototypes and of they had everyone's kitchen sink we'd still be admiring them in Pasadena. My mental image of a trencher is a box blade on a simple arm in the rear; to trench, drop the blade, lock it down and drive forward. I'd like to have the ability to have a nice, clean wall to examine soil profiles.



That is really groovy, Ed. I'm not sure if the sulfate deposits are an on-going process or if they are ancient, buried and being uncovered.

If this were under terrestrial conditions, I'd speculate that sulfide-bearing rocks have weathered, created mineralized groundwater which has moved along an aquitard/bedding plane to the outcrop and the sulfate salts have crystallized out as the water has evaporated. But you need "STP" for that and this is too alien an environment for that, although the weathering and crystallization have been likely processes.

--Bill

Posted by: Burmese Mar 22 2006, 02:08 PM

Anyone want to take a stab at estimating how much of Spirit's precious power (in Watt hours) is consumed by the wheel trenching up the soil?

Posted by: ljk4-1 Mar 22 2006, 02:09 PM

I bet you a shiny Martian quarter that Squyres is sick to death
of being asked by the press how much longer the rovers have,
along with "Did you ever think they'd make it this long?"

Though he should be honored in one sense: The question is
right up there with all the Apollo astronauts being asked megatimes
what it was like to walk on the Moon. Pete Conrad had the one of
the best responses: "Great! Terrific!"

Then again, I suppose it beats the alternative: Being asked what
went wrong with the rovers and what made them crash. I'd put up
with some annoying questions from the press to be part of a historic
space mission that made it.

Posted by: sattrackpro Mar 24 2006, 10:51 AM

Don't know about watt/hrs - but know the amount of drive time will be limited at most to perhaps 10 meters per drive-day... and drive days may be two to even three days apart. At least, that is what seems to be current reality.

It has been a periodic habit in the past that weekends see no drives - I think, giving the crew as well as Spirit a bit of rest. But, this past three days of almost no movement has taken place mid-week.

Perhaps they are still 'assessing the situation' - as well as charging batteries and waiting for satellite telcom support.

Posted by: djellison Mar 24 2006, 10:54 AM

Yes - Spirit can't really afford the power of HGA DTE passes long enough to give the downlink capacity for imagery to allow safe driving. She's safe where she is, and can look after herself for now. Once Odyssey's back up and working, she'll be fully charged, and the team will have had plenty of time to look at and plan for the next few drives toward the hill.

Doug

Posted by: slinted Mar 24 2006, 12:00 PM

Coincidentally, Deborah Bass recently mentioned http://phoenix.lpl.arizona.edu/features/weblogs/deborah_bass.php that the Phoenix lander will have no DTE X-band antenna at all, and will rely entirely on MRO (or Odyssey) relay for commanding and data return.

Posted by: djellison Mar 24 2006, 12:04 PM

That'll save quite a lot of mass, volume, power and thus money

I think it's fairly safe to do so, you have MRO as primary, Odyssey as backup, MEX as backstop. I'd have thought perhaps an LGA might be usefull just for redundency and acknowledging the transition to a new daily sequence.

Doug

Posted by: Marcel Mar 24 2006, 05:39 PM

Crew, yes...Spirit, no. The more spirit is on her own doing no science, the more dust will accumulate. And thus loss of potential for getting us scientific data within her lifetime.

Posted by: djellison Mar 24 2006, 07:50 PM

I think we've seen that in the long term, dust deposition isn't really a problem.

Doug

Posted by: kungpostyle Mar 25 2006, 11:54 AM

Looks like we are moving again, new pics on exploratorium

http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2006-03-25/2F196323968EFFAQB6P1211L0M1.JPG

Posted by: Tesheiner Mar 25 2006, 09:26 PM

Those pics were taken on sol 788.
Given the amount and kind of data available (there are Oppy's images too!) I can only think that Odissey is back on-line.

Posted by: mhoward Mar 26 2006, 01:51 AM

Spirit Sol 788 L257 false-color:

http://www.flickr.com/photo_zoom.gne?id=117886038&size=o

Yes, Odyssey must certain be working again

Posted by: Jeff7 Mar 26 2006, 02:15 AM

Darn nice and colorful there. All kinds of fun minerals and such.

Posted by: alan Mar 26 2006, 03:03 AM

Three frames Autostitched

Quite a contrast between the two tracks

Posted by: mhoward Mar 26 2006, 03:30 AM

Yes, at first I thought it was just a color balance difference in the third frame, but that doesn't seem to be the case.

Here are some more views:

http://www.flickr.com/photo_zoom.gne?id=117919657&size=l http://www.flickr.com/photo_zoom.gne?id=117919327&size=l http://www.flickr.com/photo_zoom.gne?id=117919074&size=l

Posted by: Tesheiner Mar 27 2006, 02:03 PM

Spirit is inching it's way to McCool Hill (I guess that's still the plan, isn't it).

Last driving sol was 792 (yestersol), and this is the progress on the last two moves:

-> ->
(Sol 787) -> (Sol 788) -> (Sol 792)

Posted by: Pertinax Mar 27 2006, 03:02 PM

Calibrated ~True Color of the newest 'salt trench': http://marswatch.astro.cornell.edu/pancam_instrument/images/Sol790A_P2531_1_True_RAD.jpg

-- Pertinax

Posted by: alan Mar 27 2006, 03:31 PM

I've noticed the salt often shows up when Spirit unexpetely digs in, particulaly in cases when the slope does appear very steep. It makes we wonder if perhaps the salt is causing Spirit to dig in at these spots because the salt patches are less cohesive.

Posted by: dvandorn Mar 27 2006, 03:52 PM

I don't know about that, Alan -- instead of looking less cohesive, I get the impression (in this latest unintended trench, anyway) that the white (presumably salt) layer is *more* cohesive than the soil in which it's buried.

Notice that the light-toned-to-white material has left some sand-sized grains (and larger) along the wheel track, while the redder soils seem much finer, more like talc in their grain sizes.

It really looks to me like the salt deposits are somewhat more cohesive than the soils in which they are embedded.

-the other Doug

Posted by: jamescanvin Mar 28 2006, 03:21 AM

You sure did! I feel fully up to date after the last day and a half of catching up on UMSF posts!





Thanks Phil.
Although I didn't say anything about breaking Spirit along the way, and can we see Victoria yet? I'm not so sure.

James

Posted by: Pertinax Mar 28 2006, 08:44 PM

I recently contacted Dr. Kirk of the USGS' Astrogeology group inquiring about the availability of MOC NA generated elevation maps. In reply, he was kind enough to point me toward: ftp://ftpflag.wr.usgs.gov/dist/pigpen/mars/usgs/topo/moc_na/gusev_hills_dem.zip

The resulting maps that I quickly put together today (with Microdem) I thought be worth sharing. I was unable to use a mars projection, so the results are not perfect, but all things considered, still reasonable.

-- Pertinax

- Columbia Hills - Elevation (as provided in the ZIP above)

- Columbia Hills - Ridges


- Columbia Hills - Slope

- Columbia Hills - Slope Aspect

Posted by: climber Mar 28 2006, 10:11 PM

This is not only helpfull : this is beautifull.
I'm particularly interested in the Slope rendering. Even if we all know it, Spirit is very close to a nice north facing slope in the South-East of her actual position that show very well on this picture :

- Columbia Hills - Slope

Posted by: Shaka Mar 28 2006, 10:43 PM

Ooooohhh! Pretty! Pretty! Me like'um plenty much!
Want'um legends bilong dispela color scales! You got'um?

Still worried about getting there, chaps. Today's update from our beloved managers only covers up to a week ago!
Sol 788 (March 22, 2006): The flight team planned to have Spirit drive approximately 11 meters (36 feet) to a new waypoint.
Say wha'? Does anybody know what has happened since? The silence out of Spirit is altogether redolent of the grave!

Posted by: Pando Mar 29 2006, 03:04 AM

The delays have been due to Odyssey safe mode, and restricted sols. Ody is now out of safe mode, and rovers are in a recovery mode. Because of the power situation they are in a hurry to get moving when the normal downlink is established with Odyssey, sometime this week.

Posted by: Bob Shaw Mar 29 2006, 11:50 PM

I was interested to see a nice exhumed crater in the recent MEX Libya Montes image - here's a crop which shows it. It sort of puts Home Plate in perspective... ...my back of the envelope size for it is about 5km across, though I could be wrong, wrong, wrong!

Bob Shaw

Posted by: jamescanvin Mar 30 2006, 05:28 AM

These are very nice, good job.

Any chance you could make one showing the component of the slope in the north-south direction?

Cheers, James

Posted by: Tesheiner Mar 31 2006, 08:24 AM

Spirit "moved" also on sols 794 and 796 (tosol), making an almost 180º turn since sol 787.
Mmm, what's the plan?

Posted by: general Mar 31 2006, 08:50 AM

I think she's trying to get away from that sandy patch. I hope she's not got stuck.

Posted by: Tesheiner Mar 31 2006, 08:58 AM

Looks like they are making this (aprox.) 180º turn trying to drag the stuck wheel as less as possible i.e. turning around that wheel.

Let's see if there is a new status update today; the last one is a bit old.

Posted by: odave Mar 31 2006, 01:55 PM

I seem to remember reading somewhere (my Google is failing me right now) that "spin" turns are difficult on five wheels, so that may be why we're seeing "pivots" instead.

Posted by: mhoward Mar 31 2006, 02:29 PM

Wow, you're right - I hadn't figured that out yet.

Here is a http://www.flickr.com/photos/marscat/sets/72057594095039215/show/. This is the first time I've tried making a Flickr slideshow - it's kind of slick, but I wish there was a way to view it in a larger size.

Posted by: centsworth_II Mar 31 2006, 05:19 PM

Maybe they want to try pushing the dead wheel on drives East and see how it compares with pulling it. I don't think they've decided to go back and park on the north face of Homeplate for the winter.

Posted by: ToSeek Mar 31 2006, 06:52 PM

Should we change the thread title to "Ooze Toward The Hills"?

Posted by: Shaka Mar 31 2006, 08:01 PM

It was beginning to look like "Burrow toward the Hills" was the plan (or else Spirit was preparing to lay eggs )
Now however we have some authoritative information from our beloved managers (3 hot wahines and a groovy kane): SPIRIT UPDATE: Difficult progress with five-wheel drive - sol 790-797 , Mar 31, 2006:
http://marsrovers.jpl.nasa.gov/mission/status.html
Thank you, guys! Here's hoping we can soon move out of this salty quagmire. If in doubt, remember the key lesson from Purgatory Dune:
Throw it in reverse and gun it!

Posted by: RNeuhaus Mar 31 2006, 08:05 PM

The rockier is the land, the easier would be the driven toward the McCool due to the greater sleepage.

Rodolfo

Posted by: Shaka Mar 31 2006, 08:09 PM

Yeah, that too.

Posted by: Jeff7 Apr 1 2006, 01:53 AM

Hey now, that's exactly how they got into Purgatory Dune.
They had to pop it into forward and gun it.

Posted by: Shaka Apr 2 2006, 07:28 PM

No one else has mentioned it, so I thought I'd point out the latest Planetary Society progress report on MER:
http://www.planetary.org/news/2006/0331_Mars_Exploration_Rovers_Update_Spirit.html
It looks like Spirit is pretty well bogged down, as we imagined, and the planners are doing some of the same kind of debating of strategies for progress as we have recently. E.g.:

About all I can say now is "Good luck, guys." I'm convinced McCool Hill's north slope is the only place we can carry on the mission more-or-less normally and with optimal productivity. I'm not at all confident Spirit will last another 300 sols, so just hibernating on a little local patch of north slope, in the hope of getting back to work in spring, is tantamount to giving up. It would be nice if we had a spare month to try out different motoring strategies in the Mojave Desert, but we don't. I think we'd better do what Steve said got us out of Purgatory: Gun it in reverse until we're out and rolling. Disable the slip monitor. I can feel the chill approaching.

Posted by: djellison Apr 2 2006, 08:01 PM

And it'll get even colder for longer if 'gunning it' creates a purgatory situation instead of saving us from one.

Doug

Posted by: Shaka Apr 2 2006, 08:18 PM

True, Doug. You pays your money and you takes your chances. But where we are now is not good enough to hibernate in, so we must get out to survive. The clock is ticking down. How much time have we left before we are finished without a north slope? Maybe it's already too late to make McCool.

Posted by: djellison Apr 2 2006, 08:23 PM

Indeed - so commanding activities that could get us very stuck really isn't a good idea is it?

Doug

Posted by: general Apr 3 2006, 06:56 AM

http://www.planetary.org/news/2006/0331_Mars_Exploration_Rovers_Update_Spirit.html

Quote: At this point, the team hasn't decided whether or not Spirit will actually try to hit the slopes of McCool Hill, Arvidson said. "Spirit is on the edge and there's a very strong desire to get the rover tilted north and it may not be climbing McCool Hill. It may just be finding a local hill in an interesting area. It doesn't have to be a huge hill. We have a five-wheel drive vehicle now and that's making it a little bit tough to do slopes and sandy areas, so we're reevaluating the approach to be used for the rest of the mission. It really has to do with the extent to which that wheel dragging makes it more difficult either forward or backward to go onto slopes, particularly sandy slopes."

As it turns out, McCool Hill is, after recently revised calculations, taller than Husband Hill and the tallest of the seven hills in the Columbia Hills, so hiking up McCool could be Spirit's greatest challenge yet. "But I'm not sure the vehicle in its configuration with 5-wheel drive is as good a climber as it was with 6 wheels," said Arvidson. Still, McCool is alluring so the team is assessing the possibilities and will be discussing them next week. "It might be just going to the base of McCool Hill and tilting north," said Arvidson, "and then driving back and forth along the base on the north facing slope."

Posted by: Tesheiner Apr 3 2006, 08:36 AM

Post-drive images for sol 799 are already available at the exploratorium.
http://nasa.exploratorium.edu/mars/spirit/forward_hazcam/2006-04-02/2F197299111EFFAQHAP1211L0M1.JPG

It looks like Spirit is "undoing" it's previous path and is currently somewhere inbetween sol 782 and 787's positions.

"Happy" sol 800, Spirit.

Posted by: edstrick Apr 3 2006, 09:18 AM

I'd hate to imagine the bill if they decide to call for a tow-truck.....

Posted by: chris Apr 3 2006, 10:21 AM

There is an interesting bit of curled up crusty material in the right hand side of that image..

Chris

Posted by: sattrackpro Apr 3 2006, 11:21 AM

Don’t count Spirit out just yet. Yes we’ve reached Sol 800 - the day they hoped to be snugly ensconced on a slope of choice. But, there is yet a bit of time to get there...

Today it is April the 3rd on earth but on Mars it is Monday, the 16th of May - not even at the midpoint of Autumn in the southern hemisphere of Mars. The days and nights are colder, but far from the coldest days coming up just after the middle of June (Mars calendar) when Mars reaches apsides (pronounced ‘ap-si-deez’) at its furtherest point from the Sun. Winter actually begins in the southern hemisphere - on July 10th - Mars date, at the winter solstice. See the seasonal orbit plot below, with arrows point to where Spirit is now on the calendar, noting the middle of May, and the 63rd, or end of May - and also see http://cmex.ihmc.us/cmex/data/MarsCalendar/index.html, for an in depth look at the Mars calendar.

How much slack we have to get to the best site available - before things get very dicey - only the pros at NASA know. A wild guess might be at least another 15-20 days. Cutting it close? Yes. Possible? I’d think so... but driving results in the next 10 days will tell the tale. The biggest problem faced right now is the inability to drive but every other day - and traction!

Posted by: sattrackpro Apr 3 2006, 12:12 PM

Well - hope it isn’t so... but, from the latest images down, it appears Spirit is beating a hasty retreat back toward Home Plate... possibly to climb up on the sides of a couple of small rises to the southeast of the top of HP itself, near where Spirit was on Sol 774. Not the most exciting place to park for weeks on end - but, maybe the only choice under the conditions extant.

See possible emergency parking sites (red arcs) in the images below.

Say it isn’t so, and I’ll hope right along with you. But, I’m convinced the path is back to HP, otherwise why drive so far in the reverse direction, and not toward McCool?

If this is the plan, then we’re much closer to entering a period where we can’t get enough sun than we are to very cold weather... and it could be a very long, dull and perhaps dicey winter.

Posted by: climber Apr 3 2006, 12:32 PM

I see again this "Tau" evaluation as been assessed by the rovers in the recent reports. Do you think that clouds could be an issue too ? Fortunately it doesn't seams that this year is a bad one for global or local sand storms. Is the season over yet ?

Posted by: sattrackpro Apr 3 2006, 12:43 PM

Clouds will not be an issue - nor sand storms (they happen during the summer.) Summer (wind storm time) on Mars begins about the middle of our July and ends about the middle of our Novermber (a swag, really.) The Summer soltice begins about our mid September.

Someone who has watched the dust devils on Mars can probably tell you about when they ended - and when they began.

Posted by: Bob Shaw Apr 3 2006, 01:26 PM

Doug:

I wonder if the folk driving Spirit are regretting those rather dramatic assaults onto the top surface of Home Plate now?

Rough play breaks even the best of toys...

Bob Shaw

Posted by: climber Apr 3 2006, 01:42 PM

Personaly, I don't think so. Even if they kind of play it safe, they keep pushing hard. Nevertheless, I wonder, when they say that they consider each Sol as if it was going to be the last Sol, how much they believe in that.

Posted by: mhoward Apr 3 2006, 02:51 PM

I'm guessing she's heading for the little ridge to the southeastwest. In addition to providing a north-facing slope, it might provide a safe route around the sandy area they've been struggling with for the last several sols. As it happens I was just looking at it last night, and thinking "oh - they should have gone that way!" Perhaps the rover drivers have been thinking the same thing.

I'd be really surprised if they were heading back to Home Plate, but I guess you never know.

Posted by: mhoward Apr 3 2006, 03:03 PM

http://www.flickr.com/photo_zoom.gne?id=122617588&size=o of the ridge from back on Sol 779, just after she left Home Plate and right before she waded out into the sandy area. One nice feature of the ridge is it might provide a little peek at "Pitcher's Mound", but mainly I'm thinking they'll follow it west east right around the sandy area. The view is facing due South. Edit: If you can' tell, I'm optimistic - they are at least out of the sand trap, and perhaps headed in the right direction. Second edit: If you can't tell, I'm directionally challenged - had "west" and "east" confused for a bit there.

Posted by: Shaka Apr 3 2006, 08:17 PM

Here's a little something in Spirit's recent wheel trench that has another forum stumped - and me too
http://www.flickr.com/photos/hortonheardawho/121890890/
Any regolith experts out there who can help with a diagnosis?

Posted by: sattrackpro Apr 4 2006, 01:16 AM

I'd be surprised too - if they actually returned to the top of HP... but, not if they go back to one of those rises just off HP. How long they stay there, or what route they take from there is what everyone wonders about.

I just hope they haven't given up on getting to better digs on the side of McCool - but, conditions and circumstance might preclude that. Whatever they decide, I'm sure it will be consistent with the best way to keep Spirit alive through the winter.

Posted by: Pando Apr 4 2006, 05:09 AM

I think considering that Spirit's energy is down to low-300 Whrs it's already getting dicey. They have to move to some local mound fast to tilt the rover. The flip side is that they can't just "gun it" due to the already low power available.

Posted by: sattrackpro Apr 4 2006, 07:37 AM

Is there anyplace where they post the days power readings? I would sure like to know what they are... and I guess everyone else would too.

Posted by: djellison Apr 4 2006, 07:41 AM

Not that I've found - we try to keep track of them as and when they are mentioned, but day to day figures are not even at the PDS, they seem be mentioned as more of an anecdotal figure than one of genuine scientific value.

Doug

Posted by: Tesheiner Apr 4 2006, 08:56 AM

This is from a http://www.newscientistspace.com/article/dn8944-mars-rovers-broken-wheel-is-beyond-repair.html; nothing really new on it except for this mention of three possible "safe-heavens".

Posted by: sattrackpro Apr 4 2006, 09:32 AM

Tesh, if they want to do science, I just can not imagine them not making another try to get on McCool in some way.

Perhaps the alternate route around the sand will be through the somewhat rocky area just to the south of where the rover is now. Maybe the plan is to backtrack, then jog south, something like the green trace in the following...

(edit) The problem with that route may be some pretty steep climbs in spots.

Posted by: odave Apr 4 2006, 02:01 PM

...but certainly one of pretty high engineering value - would that push it behind the ITAR curtain?

Posted by: jaredGalen Apr 4 2006, 03:42 PM

With the permanent loss of the wheel, the next problem may be the distribution of the lubricant and it's potential to cascade into some nastiness.

Just how much more difficult is it to push the crippled wheel than to drag it?
A lot more I would think, so, now that winter is creeping in, will the lubricant be more susceptible to becoming unevenly distributed?
Perhaps spinning of individual wheels while stationary in the backwards direction, which sounds like a waste of mileage really...

Posted by: helvick Apr 4 2006, 03:55 PM

I don't think the daily power numbers alone would fall foul of ITAR but any decision to make a habit of publishing them would have to be cleared and the interest in them is marginal so I think the effort has been better spent elsewhere, even if sad geeks like me would just love to see them.

We have already seen some interesting derived numbers published (as in http://www.unmannedspaceflight.com/index.php?showtopic=1718&st=0# in the "Oppy vs Spirit Power Consumption" thread) so they can't be considered too dangerous.

I've used the efficiency chart in the above comment as source data to add what is hopefully a much more accurate trace of power generated per sol to my power estimation charts.
Blue Line - Estimated theoretical maximum power (no atmospheric or dust losses, horizontal panel).
Purple Line - Estimated theoretical maximum power factoring in Tau (atmospheric losses), using the published Tau values for the MER Analyst Notebook.
Green Line - Estimated power including both atmospheric losses and dust losses (using the efficiency chart above).
Red Line - Interpolated estimated power based on actual reported figures and assuming steady state dust build up leading to additional efficiency losses of 0.18% per sol. That appears to be consistent with the recent rate at which power levels are dropping and it is a lot worse than it seemed to me to be at the start of March (0.08%).
Blue dotted line - Supposed minimum survival level.

Areas where the red curve is above the green curve are times when Spirit's orientation was tilted towards the sun and gains of 22-25% have occurred in the past, hopefully they will be again fairly soon.

It's all quite messy but it does show the problem times that are ahead. As things stand if nothing else changes power will drop to 280whr per Sol on Sol 828 and could drop as low as 204whr by Sol 950 unless the drivers can get her to a safe haven.

Posted by: indy Apr 4 2006, 04:11 PM

There are some clips here of when they practiced driving on 5 wheels backwards previously when the front right wheel was drawing too much power. You can see in the clips how pushing it causes it to dig in so dragging works out better.

http://marsprogram.jpl.nasa.gov/gallery/video/2001-2004.html

Yes, I would think lubrication would be a worry and wouldn't the constant dragging be more of a strain on the other wheels?

Posted by: Nirgal Apr 4 2006, 05:27 PM

helvick, do you also have an updated Oppy chart, counting in this effect of much-worse-than-expected
dust loss factor ?
Do you think, that at this rate of dust-loss the power situation could even even become crititcal for Opportunity within the next 100 sols ?

Thanks
Nirgal

Posted by: helvick Apr 4 2006, 06:16 PM

I haven't seen any update on Oppy's power since early march so I didn't repost that chart and I don't have much reason to think that the dust situation on Oppy has similarly disimproved.

The dust deposition rate should primarily track the seasonal changes in Tau (as that is an indicator of atmospheric dust loading) so the apparent change for Spirit surprised me a bit since tau should be dropping steadily down towards 0.5/0.6 with the onset of SH winter.

The decrease in performance since early March (from 370whr around Sol 774, 350 around Sol 781 and 330 around Sol 794) could well be due to orientation of the panels and not additional dust so without confirmation on the cause my assumptions should be taken for what they are - amateur speculation.

But to answer your question if dust deposition is the reason for this and if Oppy is experiencing the same dust levels as Spirit then her minimum power level will drop to 339 whr on Sol 937 and start to rise again on Sol 966. With my prior estimate of 0.08% dust deposition loss rate those numbers were 405whr on Sol 902 and rising again from sol 925.

Posted by: Nirgal Apr 4 2006, 07:09 PM

thanks helvik ! as always, very informative answers

Posted by: Jeff7 Apr 4 2006, 07:28 PM

Spirit sure made http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2006-04-04/2F197297371EFFAQGMP1290L0M1.JPG, but is making slow progress again.

Tesheiner mentioned the little curly thing in http://nasa.exploratorium.edu/mars/spirit/forward_hazcam/2006-04-02/2F197299111EFFAQHAP1211L0M1.JPG. Anyone ever figure out what it might have been? Just some really weird rock formation?

Posted by: RNeuhaus Apr 4 2006, 07:41 PM

A curved and lamined stone is very strange for a geological formation, IMHO, unless it is related to any kind of biological material which is capable to make these in odd shapes. However, it would be silly to say that this is might be a biological material. Maybe someone have seen that formation based of stone material.

Rodolfo

Posted by: dilo Apr 4 2006, 08:19 PM

I didn't see these movies previously, they are very impressive and not very encouraging, looking to the huge slippage increase and steering difficulties arising from only one blocked wheel.
Anyway, did someone noted this strange, thin "whormhole" in the sand ?
http://qt.exploratorium.edu/mars/spirit/pancam/2006-04-04/2P197380695EFFAQHAP2401L5M1.JPG (look almost at the center of the picture). cannot find reasonable explaination...

Posted by: ElkGroveDan Apr 4 2006, 09:13 PM

Let's not jump to conclusions now.

There's no evidence this was made by a "worm". It could just as easily been made by an insect, a rodent or a very small humanoid pulling a sack full of rocks back to his lair.

Posted by: Shaka Apr 4 2006, 09:32 PM

http://marsrovers.jpl.nasa.gov/spotlight/20060404.html
Now, that's what I'm talkin about!
An excellent Rover Feature update on the Spirit dilemma, including great topo and energy maps!
http://marsrovers.jpl.nasa.gov/spotlight/spirit/20060404/20060404_1143219799_31986-1_FagetArea_3D_Energy_060331130029.jpg
Go for Blue, guys!

You tell 'em!

Posted by: lyford Apr 4 2006, 09:54 PM

If you mean this bit, it looks like the rock got plucked out by the wheel rolling over it and left a hole...

Posted by: paulanderson Apr 5 2006, 12:29 AM

Why would it be silly? Even the MER team admits that a few odd things seen so far have been puzzling, such as the "rotini" for example, although none were distinctly biological-looking enough to say "eureka!". I don't rule out the possibility though. Maybe one of these days...

Posted by: ElkGroveDan Apr 5 2006, 02:08 AM

No I believe he meant this:

Posted by: dilo Apr 5 2006, 06:05 AM

Absolutely yes.
This is a comparison between images taken from L1 and R5 (it works also like a crossed-eyed stereogram):

It seems a track caused by a rolling object, but I do not clearly see the object and, if it is a rock, the pushing force (slope or wind) should be too weak!

Posted by: MizarKey Apr 5 2006, 06:51 AM

Thanks Dilo for the stereo image. I took the images into PaintShopPro and enlarged them to try and get a better view of the 'end' of the trail. It almost looks like there may be a crevasse of some sort under the sand and Spirit's close passage caused a sinking along the length of it.

It would be nice if they could investigate it just a little better, rule out 100% the possibility of some weird critter leaving the rock and trying to make a run for it.

Posted by: Tesheiner Apr 5 2006, 09:53 AM

According to the tracking web, sol 801 (tosol) was supposed to be driving day.
However, today's top priority images have been already downlinked and correspond to a 180º navcam taken on the same place as sol 799.

I assume Spirit currently doesn't have enough power to take a pre-drive panorama AND drive AND shoot the post-drive images, so I would say tosol plans have been changed and we'll have to wait for tomorrow's plan to see the rover moving again.

Posted by: mhoward Apr 5 2006, 03:46 PM

Another Flickr slideshow experiment: http://flickr.com/photos/marscat/sets/72057594099533418/show/.

Posted by: RNeuhaus Apr 5 2006, 04:21 PM

The rover's suspension system, which keeps all six wheels in contact with the ground with a weight evenly distributed on all six wheels. That keep the rovers balanced so they don't tip or roll backward.

It also prevents relief against the dragging right-front wheel disrupting Spirit's progress, however, because it continues to maintain equal weight on it.

For me, this will be very difficult for Spirit to advance a soft sand. One of the best solutions for this is that the rover rover must try to rover on any outcrop or low deep of sand and also, of course, the stuck wheel must be back of the rover, so that the otheres two healthy wheels open a track that the stuck wheel will meet less resistance. If all are not possible, look for a close place where the Spirit can tilt properly its solar panels against the sun. Any other more ideas to solve that problem?

Rodolfo

Posted by: centsworth_II Apr 5 2006, 05:22 PM

there have been discussions in this forum of what useful life the rovers could have after an end of mobility. Think of this as a preview. If Spirit gets to a north-facing layered outcrop, think of the monster microscopic mosaic that can be made. Think of the timelapse studies of dust and sand movement around the rover. Think of the weeklong mossbaur and APXS integrations.

Hopefully Spirit will make it throught the winter and can continue trekking, however slowly, in the spring but in the meantime, there is lots to do, even standing still.

P>S> Where's that dust cleaning event?

Posted by: helvick Apr 5 2006, 05:50 PM

Depends on the wind and we can't really expect that to be strong enough until very close to the SH vernal equinox when the arrival of spring begins to heat things up.

Spirit's first definite major cleaning event occurred on sol 420\421 so I wouldn't expect any until sometime around Sol 1089 give or take a couple of weeks. Opportunity had a couple of minor (5%) cleaning events while in Endurance (between Sol 120 and 250 which is around this time of the year) so there is some possibility of a minor event but I think it is slim given the fact that Spirit didn't see anything similar last time around.

Posted by: odave Apr 5 2006, 06:57 PM

IIRC Spirit had also gained some altitude on Husband Hill when the cleaning events started. I know she's in "any port in a storm" mode now, but I wonder if the blue areas at a higher elevation on the http://marsrovers.jpl.nasa.gov/spotlight/spirit/20060404/20060404_1143219799_31986-1_FagetArea_3D_Energy_060331130029.jpg would be good to shoot for - to try to catch what wind there is.

Posted by: Shaka Apr 5 2006, 07:04 PM

I hate to say it, but I fear that where we are now may be one of the worst places to look for a cleaning wind. The morass of fines we have just been stuck in collected here because it is a trough of minimal wind velocity. Remember all those parallel windstreaks behind every pebble up in the crest of Husband Hill? Find any around here. http://marsrovers.jpl.nasa.gov/gallery/all/2/p/778/2P195430351EFFAPGBP2388L5M1.JPG
If we remain in this area I expect the solar panels will just get dustier and dustier until they die.

Posted by: sattrackpro Apr 6 2006, 06:49 AM

There's two tidbits of information in a MarsDaily.com article today (at http://www.marsdaily.com/reports/Spirit_Team_Facing_Critical_Decision_As_Martian_Winter_Approaches.html) - that winter is "still more than a month away" and that, "... minimum sunshine in the Martian winter is more than 100 days away."

Not much else is new in the article, and it restates the current goal of, "moving laterally to a different slope that should be easier to climb and will provide the maximum available sunlight for the rover's solar panels."

With being able to drive for only about an hour per day - with an average best-case advance of 20 feet per day, it would take roughly16 days to travel the estimated 100 meters to one of the three alternative sites they have mentioned. Expecting that turns, which are very tricky now, will take up to two days to negotiate - I'm guessing we won't see a safe spot until about four weeks from now - that is, if indeed we are headed for a spot "about 100 meters away."

Lets hope we can get some longer drives behind us, as soon as we get on this upcoming altenative path!

Posted by: Tesheiner Apr 6 2006, 07:54 AM

Spirit moved again on sol 802.
Fhaz: http://nasa.exploratorium.edu/mars/spirit/forward_hazcam/2006-04-06/2F197562169EFFAQI8P1211R0M1.JPG


Here is a navcam mosaic taken at the previous position with my guesstimation for the current site.
The rover seems to be approaching a nearby "northern slope" (point A) but the question is if that's a contingency "winter's quarters" or just a waypoint on the route to McCool Hill (towards B ).

Edited: current position re-adjusted.

Posted by: Tesheiner Apr 6 2006, 09:44 AM

And this is the "drive-direction" pancam mosaic taken on sol 802.

I think it's time to say good bye to McCool Hill winter quarters.

(193k)

Posted by: climber Apr 6 2006, 11:07 AM

I don't agree. It has been said (two posts above) that they're trying to get rid of sandy's part, then, that it'll take like 1-2 days to make a turn because of the dead weel : it's consistant from where you show we are. So, I keep thinking that we're still going to McH...

Posted by: djellison Apr 6 2006, 11:23 AM

At some point you have to cut off and say "right - we wont make it across this terrain, it's too uncertain and the time isnt there to guarentee getting onto the slope beyond" and then make for smaller good slopes, the sort that we disregarded before the FR wheel packed up as being too limiting w.r.t continued exploration during winter.

I don't know if that point has passed, but the ammount of imaging they've done of the slope at the SE edge of HP would suggest that they might camp there - there's a few M of exposed outcrop to explore, a 360 degree pan to be had etc etc.

I guess we'll find out sooner or later if that decision has been taken or not.

Doug

Posted by: sattrackpro Apr 6 2006, 11:51 AM

Doug, I tend to agree on this rise being a possible candidate - the North side of it. Using Tesh's 'drive direction' image - IF (a big one) this is the goal - I'd say they'll scoot (limp) around to the North side of it, something like the green line suggests. Then I would expect later travel to the North side of another greater rise just to the west of it.

This wouldn't be a bad place to camp, and get the power up - as it may afford short visits for continued HP examination - something many people wanted to see.

Posted by: sattrackpro Apr 6 2006, 12:08 PM

I fear you are right about the conditions here, especially below HP in that valley - but, there is one possibility that stands out from photographic evidence - the top of HP is pretty bare. There's not much dust accumulation up there - so it's possible this rise we're looking at will have enough wind at some point for a cleaning job. But, I'd guess that will be many... many weeks away.

I'm not at all certain - but, I wouldn't be surprised to see Spirit doing a lot of 'deep sleep' in the coming months - perhaps starting more or less right away. We just don't know what the battery level is, or what the daily charge rate is right now. From what can be gleaned - it can't be very good.

Posted by: abalone Apr 6 2006, 12:33 PM

This makes perfect sense to me. As mentioned before they can not lift the dead wheel but they can reduce the weight on it by driving west backwards on a north facing slope, thus tilting the rover to place more weight on the side with three good wheels as it climbs higher

Posted by: Bill Harris Apr 6 2006, 12:34 PM

I imagine that Spirit will scoot to that nearest north slope on the Mitchelltree Ridge line to weather the winter and then decide what to do next. Clearly, she will need to explore around (or on) Homeplate since long journeys are out of the question. We've seen dust tails behind pebbles here so I think that the wind may be sufficient to keep the solar panels clean, depending on wind direction _vs_ panel orientation.

There is still a lot of science left in this three-legged dog...

--Bill

Posted by: abalone Apr 6 2006, 01:02 PM

Less likely to me, going east means three legged dog has broken leg on down hill side not uphill side and therefore more weight

Posted by: mhoward Apr 6 2006, 02:26 PM

Here is a three-image http://www.flickr.com/photos/marscat/sets/72057594100294380/show/ or wherever she's heading for. These are Navcam views facing West, from Sol 792, 799 and 802.

Posted by: jvandriel Apr 6 2006, 05:00 PM

A view of the wheeltracks from the other side.

Taken with the L0 navcam on Sol 799.

jvandriel

Posted by: mhoward Apr 6 2006, 05:25 PM

Here are a few images from way back on Sol 776-779, showing the north-facing slope(s) we might possibly be heading for. First is a view facing directly South, so you can tell we are looking at some north-facing slopes. After that are a couple anaglyph version of the same view for those who like that kind of thing. Finally is a wider view, showing another potential stopping area to the right? That one happens to be almost on the edge of Home Plate, interestingly enough.

http://flickr.com/photo_zoom.gne?id=124237854&size=o http://flickr.com/photo_zoom.gne?id=124237842&size=o http://flickr.com/photo_zoom.gne?id=124237837&size=o http://flickr.com/photo_zoom.gne?id=124277187&size=o

One wild thought that crosses my mind: Would it be possible to go *over* this rise and make a dash for "Pitcher's Mound"? Sure, probably too dangerous...

Posted by: Bill Harris Apr 6 2006, 06:03 PM

That might be a possibility. We need to get to that slope directly south ASAP since that is a secure spot for the immediate future. Safest route for continued exploration would be to stay on the hard-surfaced Homeplate surface. But we could do a survey of the route to PM from atop that rise and decide what to do when the insolation increases.

--Bill

Posted by: jvandriel Apr 6 2006, 07:19 PM

How about this view.

A complete 360 degree panoramic view taken on Sol 799 and Sol 800

with the L0 navcam.

jvandriel

Posted by: Nix Apr 6 2006, 07:28 PM

Sweet work, always improving -thanks jvandriel for the continuous contributions.

Nico

Posted by: Shaka Apr 6 2006, 08:12 PM

Excellent, JVan, and I can finally see what the drivers might have in mind. Instead of the left turn at the knoll toward "B", as Tesh suggested, They might be planning a right turn (toward "C"). It a fairly long trip, and I don't know if there is time and energy to make it, but I think it's worth a try. We will get pretty bored over 300 sols looking at the 'spongebob' basalt on the north side of that little knoll.
Now to see if I can make this image appear, without setting off Doug's alarm bells...

Posted by: Tesheiner Apr 6 2006, 08:23 PM

IIRC, that area in the midpoint between A and C is a "red zone", meaning it has a southern slope.
Spirit would have not enough power to survive traversing by that area.

And wrt going *over* the hill Spirit is currently headed, there was also a "red area" on the top of it.

Posted by: djellison Apr 6 2006, 08:32 PM

Shaka - the area you've labelled 'safe' is the exact opposite, that's a south facing slope. A few days on that and Spirit would be dead.

The slope that can be seen against the skylin between your A and B points is north facing and the sort of slope they require.

Doug

Posted by: Shaka Apr 6 2006, 09:01 PM

Doug,
Wow, can I possibly be that confused about my Martian geography. The blue blob I labelled "Safe" is supposed to correspond to the blue safe area behind Korolev in JPL's 3D Energy Map (see yellow arrow)


Yes, B is the little "knoll" I mentioned. A place with probably nothing to study but vesicular basalt for 300 sols.
If that is our fate, so be it. But I would hope for more. The A to C path is supposed to pass in front of Mitcheltree Ridge so the panels don't tip south.