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Posted by: jamescanvin Dec 15 2008, 07:12 PM

Conjunction is over, so it is probably a good time to start a new thread.

I just saw this update from http://twitter.com/marsroverdriver

Posted by: mhoward Dec 15 2008, 07:32 PM

That's great news. I was starting to get a little worried about Spirit (again). Looking forward to a status update.

Posted by: fredk Dec 15 2008, 08:07 PM

Still no new images at exploratorium, though. I hope we can interpret that somewhat ambiguous twitter message as meaning that they've actually heard from Spirit...

Posted by: mhoward Dec 15 2008, 08:16 PM

Hmmm. Good point.

Posted by: RoverDriver Dec 15 2008, 09:18 PM

We heard from both rovers. MER-A is around 190Wh I heard. Today's drive was postponed for several reasons. Time is running out on our attempts to climb uphill.

Paolo

Posted by: dvandorn Dec 16 2008, 05:39 AM

OK, I'll admit my ignorance -- what was wrong with the idea of driving downhill and making our way around Home Plate on the ground below? As I recall, the parking spot was selected with the idea of driving down, not up, in mind.

-the other Doug

Posted by: centsworth_II Dec 16 2008, 06:39 AM

The trip to the post winter objectives south of Home Plate would be quicker if Spirit could cut across the top -- more direct, easier terrain.

Posted by: RoverDriver Dec 16 2008, 03:21 PM

Not to mention we have already driven on it and we have ground based imaging.

Paolo

Posted by: climber Dec 16 2008, 03:25 PM

How much do we have to drive to get the solar panels leveled?

Posted by: RoverDriver Dec 16 2008, 04:32 PM

One or two drives worth. The ramp were we are parked is quite short, maybe 1-1.5 mt? I don't recall exactly.

Paolo

Posted by: peter59 Dec 16 2008, 09:17 PM

Everything indicates that we are after the solar conjunction. I'm not sure, but the time in the name of the files is significantly higher.
http://qt.exploratorium.edu/mars/spirit/navcam/2008-12-16/

Posted by: mars loon Dec 16 2008, 09:30 PM

I just got word from a team member that signal has been reacquired for both Spirit and Opportunity

Spirit is up to about an amazing 200 WHRs. way better than 89 !!

The next new adventures are on TARGET. The girls are ready to roll !!

more at my NJ lecture later this week at AAI astro club

ken

Posted by: mhoward Dec 16 2008, 09:47 PM

We've already heard that about seven posts up, but it's still good. 200 Wh would be news.

There is a Navcam pair on Exploratorium from Spirit Sol 1761, which is today (soon to be yestersol). No move yet. There is an existing Navcam image from back on Sol 1724, and comparing the two seems to show some changes due to wind, although it's hard for me to say how much of it is due to the lighting. The sol 1724 image was taken almost an hour later in the day.

Onward and upwards! Both in elevation, and Wh's.

Posted by: fredk Dec 16 2008, 11:38 PM

We were doing around 170 Whrs before conjunction, so 190 or 200 is pretty good. I'm not sure, but that seems like too big an increase to be due to just the increase in sunlight as we head into spring. So maybe dust is clearing from the air (tau is dropping) faster than the dust is falling onto the arrays, raising the dust factor. Or maybe we had a small cleaning event?...

I've been wondering about the optimal tilt for the arrays. Is anyone keeping track of the maximum solar elevation these days? If we drove onto level ground now, would that improve or worsen the power situation?

Posted by: peter59 Dec 22 2008, 08:54 PM

Unfortunately, rover is increasingly pushed to the right. This tendency worried me.
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2008-12-21/

Posted by: alan Dec 22 2008, 11:05 PM

If they get all three wheels on the left side onto the top of home plate could they drive mostly parallel to to the edge until the right side wheels are on top too?

Posted by: RoverDriver Dec 22 2008, 11:21 PM

The terrain on the right side of the rover is more benign: lower slopes and smoother. Unfortunately it seems that in spite of moving to a better surface does not help making much progress uphill.

Paolo

Posted by: RoverDriver Dec 22 2008, 11:26 PM

Yes, probably that would do, but it would take several drives and very likely the rover would slip downhill adding difficulties to an already complex situation. At this time I do not think it is a good idea to change the rover heading so drastically that would affect an emergency drive downhill. As it often happens, many good ideas have to be discarded to maintain the rover safe.

Paolo

Posted by: OWW Dec 28 2008, 10:06 AM

http://qt.exploratorium.edu/mars/spirit/navcam/2008-12-27/2N283673336EFFAZ55P1914L0M1.JPG

Or, or, or.... could it really be? I would like to know Spirit's power numbers now!!!!!!!!!!

Posted by: Tesheiner Dec 28 2008, 10:12 AM

Wow!
I was coming here to add a post about the latest "bump" which happened yestersol (1772) but this navcam shot, if it's trully a cleaning event, is a great gift. Thanks Santa!

<searching for a previous navcam shot...>

Posted by: Tesheiner Dec 28 2008, 10:29 AM

Got it!
Here's two shots at this same pointing; the one to the left was taken on sol 1435 while the one to the right was on sol 1772.
http://marsrovers.jpl.nasa.gov/gallery/all/2/n/1435/2N253754697EFFAX05P1914L0M1.JPG http://qt.exploratorium.edu/mars/spirit/navcam/2008-12-27/2N283673336EFFAZ55P1914L0M1.JPG

Posted by: Astro0 Dec 28 2008, 10:53 AM

Doug blowing out those 30 candles may have made a difference after all!
Animation http://astro0.files.wordpress.com/2008/12/spirit_1435-1772.gif....and detail http://astro0.files.wordpress.com/2008/12/spirit_1435-1772detail.gif

Hopefully this is not just a trick of the light and there has been some improvement to power levels.

Astro0

Posted by: akuo Dec 28 2008, 11:02 AM

Yay!

Definitely not a trick of light since you can see dust streaks on the hinged solar panel. The cells closer to pancam seem a lot cleaner! This looks like great news

Posted by: helvick Dec 28 2008, 11:53 AM

Looks like a significant change to me, can't wait to see power numbers.

Posted by: sci44 Dec 28 2008, 12:06 PM

You see? Gluing on a mince-pie, glass of sherry and a "Dear Santa" letter onto the side of the Rover is *much* more effective than adding silly wipers on the panel. This way Spirit is guaranteed to get a good cleaning every Xmas!
Seriously, if that is right, well spotted guys!

Posted by: BrianL Dec 28 2008, 04:50 PM

Back to the bump, which I perceive as intentionally downward...
Does this mean the attempts to get back on top at this spot are over?

Posted by: imipak Dec 28 2008, 05:05 PM

Is it my imagination or does the dust look a bit thicker on the rear (I think?) panels, to the right of the image? If so I hope it's not enough to negate the power gain from the cleaner panels

Posted by: Oersted Dec 28 2008, 10:46 PM

Those two pics in Tesheiners posting make it pretty evident that a cleaning event has taken place. Did we ever have such a partial cleaning before, with dust streaks on the panels? Numbers, numbers please!

->

Well spotted OWW!

Posted by: Fran Ontanaya Dec 29 2008, 02:38 AM

The rear hinge and a wire are partially covered by darker dust. And the... huh... stick, has a dark streak

Posted by: Shaka Dec 29 2008, 02:41 AM

Not before time either! http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2008-12-27/2F283675634EFFAZ57P1212R0M1.JPG
Looks like it's all downhill from here, guys.
I grok that. There's science a'waitin' along the west edge of HP!

Posted by: fredk Dec 29 2008, 05:05 AM

The dust around here is light. It may look like streaks of dark dust, but those are really the areas where the dust has been cleared.

Man, I can't wait to hear some numbers!

Posted by: CosmicRocker Dec 29 2008, 06:04 AM

Perhaps it's premature to join the cheerleaders, but are these rovers fortunate, or what? Can someone toss us a bone, for crying out loud?

Posted by: Tesheiner Dec 29 2008, 02:27 PM

While still waiting for new Whr figures, just one remark for those comparing the two navcams I posted before. The idea was to have a reference picture together with the latest image to be sure what we were seeing was real and not an image artifact. If anybody wants to make comparisions about dust levels on them, remember that the first picture was taken about one year ago and not last week.

Posted by: hortonheardawho Dec 29 2008, 06:01 PM

sol 1738-1761 R2 comparison:

http://www.flickr.com/photos/hortonheardawho/3147329251/


Another R2 of the solar cells was taken on 1772 labeled pancam_dust_motion. The stamp image actually looks dustier - so we will have to wait for the full size image download.

Posted by: Oersted Dec 29 2008, 11:29 PM

But Horton, that comparison is not with an image taken after the possible cleaning event, is it?

Posted by: hortonheardawho Dec 30 2008, 12:10 AM

The animation was made to show that there was not nuch change between sols 1738 and 1761.

The 1772 R2 pancam image when posted hopefully will show more change.

Posted by: jamescanvin Dec 31 2008, 02:00 PM

Here is a gif flick between the sol 1761 and 1772 'dust_motion' pancams

Posted by: djellison Dec 31 2008, 03:51 PM

Something's definitely happened, but those few cells visible in the Pancam frames are less convincing that the large streaks across the right rear array on the Navcam shots.

Posted by: jamescanvin Dec 31 2008, 03:55 PM

I think that this pancam is pointed at the rear of the right side array which shows very little change compared to other parts shown in the navcam image.

Posted by: RoverDriver Dec 31 2008, 04:04 PM

That is correct. This pancam subframe was used to compare its vew with the same pancam subframe we captured during the first attempt to drive uphill.

Paolo

Posted by: sci44 Dec 31 2008, 11:11 PM

I was wondering - as you know, Spirit is trying to climb up a fairly steep slope. Looking at the direction of the dust streaks as it appears to "clear", could that be consistant with mechanical vibration aiding the clearance, or is that not possible - so this is purely the wind doing the work? To what extent could the clearing be an optical illusion - ie, when there is bright light fully reflected by the panels, they appear dusty, when not, the dusty patterns on the dark panels stand out..

Just my 2 cents..

Posted by: PaulM Dec 31 2008, 11:43 PM

I was wondering if the dust movement was caused by a Marsquake.

Posted by: Fran Ontanaya Jan 1 2009, 12:15 AM

But Mars crust is dead, and probably a quake strong enough to shake the rover would make a lot of dust go airborne over Gusev.

A very small vibration can't be the solution, or that shaking mode they tried to clean the MiniTES mirror would have been enough.

Posted by: PaulM Jan 1 2009, 12:51 AM

The Viking seismometer did not detect any Marsquakes. However as this abstract makes clear the seismometer was not very sensitive and only worked on none windy days:

http://adsabs.harvard.edu/abs/1979GeoRL...6..368G

It is stated in this article that a picture taken by MRO may be evidence of a Marsquake:

http://www.universetoday.com/2008/03/03/hirise-captures-stunning-images-of-mars-avalanches-in-action/

Posted by: Fran Ontanaya Jan 1 2009, 08:41 AM

There must be a minimum seismic level the MER can directly sense if it tries to.
Would the vibration trigger the dust devil capture program if it was running (and would the microscope be able to capture movement if it was looking)?

About the avalanches, I remember from high school geology that thermal expansion, abrasion, frost weathering, weight removal or even haloclastia or chemical weathering could be involved.

Posted by: djellison Jan 1 2009, 11:56 AM

It has IMU's and Accelerometers, not Seismometers. This is an issue we've covered before here.

Even if it detected shuddering from a DD (and indeed, there is about a pixels worth of shift at the summit of Husband Hill during strong winds) then by the time the rover had stopped doing whatever it was doing ( if indeed it has the power to be doing anything at that time anyway ) - it wouldn't even know which direction to point the Navcams to take an image of the DD that would be long gone anyway.

The new software to do DD/Cloud watching is a far more sensible and productive means to achieve that sort of thing.

Doug

Posted by: RoverDriver Jan 1 2009, 02:51 PM

Indeed. We tried to see what happens to the testbed when we drop a 30lb rock from a height of about 3' near the rover. No indications whatsoever from the IMU and the drop could be felt throughout the Sandbox.
This was done in preparation for one seismic observation (MERB) during Conjunction which unfortunately was never sequenced.

Paolo

PS: Happy New Year!

Posted by: ElkGroveDan Jan 1 2009, 05:27 PM

Happy New Year Paolo.

Say....before you put down your sunglasses and took off your leather gloves left for the weekend did you happen to glance over at the dashboard? Was there a gauge labeled Wh? Can you give us a hint what it was at?

Posted by: peter59 Jan 1 2009, 05:56 PM

December 29, 2008
http://marsrovers.nasa.gov/newsroom/pressreleases/20081229a.html
"Occasional cleaning of dust from the rovers' solar panels by Martian wind has provided unanticipated aid to the vehicles' longevity. However, it is unreliable aid. Spirit has not had a good cleaning for more than 18 months."

Posted by: djellison Jan 1 2009, 06:30 PM

That article was probably penned before this suspected event anyway

Doug

Posted by: lyford Jan 1 2009, 07:12 PM

A cleaning event would be a good way to celebrate 5 years on Mars.... maybe the cosmos is just waiting for dramatic timing.

Posted by: Stu Jan 1 2009, 07:24 PM

Yep, a cleaning event would be a fantastic New Year pressie!

On the subject of celebrating, some personal "5 year reflections" http://cumbriansky.wordpress.com/2009/01/01/5-years-of-walking-on-mars... hope others will share their thoughts and memories too; it would be fascinating reading, I'm sure, especially for our newer and younger members who weren't actually there at the time.

Posted by: centsworth_II Jan 1 2009, 09:55 PM

My granddaughter was born as Spirit was working its way down Haskin Ridge from the summit of Husband Hill. Both continue to fill me with wonder. My Granddaughter must undergo daily dust clearing events!
(Happy new year to all!)

Posted by: RoverDriver Jan 2 2009, 05:34 AM

I don't have exact numbers but I heard around 150Wh. It was decided t drive down the slope and abandon the path uphill. The drive was supposed to happen middle of the week. Unfortunately the DNS station had hydraulics issues with the antenna and the sequence was not radiated. The drive was sent on New Years Eve. Hopefully the bubbles in our virtual champagne will help in bringing new Whs for the new year.

Paolo

Posted by: CosmicRocker Jan 2 2009, 06:10 AM

I've been eagerly watching for the much anticipated http://www.planetary.org/news/2008/1231_Mars_Exploration_Rovers_Update_As.html, assuming it would mention a recent cleaning event if there actually had been one. It just popped up at the Planetary Society's web site a little while ago. I see no mention of a recent cleaning event; only a comment that they are hopefully waiting for one.

Although we didn't hear the good news we were hoping for, as usual, there is a lot of other interesting news contained in the report.

Posted by: CosmicRocker Jan 2 2009, 07:53 AM

I know this is OT for this thread (move it, if necessary), but Salley's report mentioned the Garrels pan.

I'm a big fan of that geochemist. I can see parts of the pan in MMB. Has anyone assembled it in full Technicolor? His textbook is a classic.

Posted by: djellison Jan 2 2009, 08:10 AM

It's BnW pan, similar to the Lyell pan - but a bit closer to the cape, not as close as the final nice postcard of the cape however.

Doug

Posted by: jamescanvin Jan 2 2009, 12:37 PM

Garrels was taken in colour but in the end the L2 & L5 were discarded before being downlinked to free memory so it is only in L7.

Posted by: Ipparchus Jan 4 2009, 01:36 PM

I didn`t hear anywhere if there really was or not a recent cleaning event that has vanished some of the Spirit`s solar panel dust coat. I think that the photo that we all saw a few days ago in this site shows clearly that such an event really happend, but why then MER team says nothing if that`s the case?! how many watts/hours has now Spirit?

Posted by: djellison Jan 4 2009, 01:39 PM

Please read through this thread for all the information. It's been covered already.

Posted by: Oersted Jan 4 2009, 06:36 PM

I for one am still looking forward to info on an eventual change in power output...

Posted by: centsworth_II Jan 4 2009, 08:08 PM

I'm looking forward to the next Spirit update. If Rover Driver's comment, "around 150Wh", reflects an accurate post dust pattern "change" figure, then apparently there was no change as far as power goes.

Posted by: Tesheiner Jan 4 2009, 08:47 PM

FWIW, there is a deck mosaic planned to be taken today (sol 1780) with the navcam.

01780::p1914::02::5::0::0::5::0::10::navcam_5x1_deck_LEYE_3bpp

Posted by: Astro0 Jan 4 2009, 09:22 PM

While we wait for power numbers, movement, deck pans etc, here's a fun Bonestell polar panorama with virtual rover (and some virtual ground) to enjoy.

...and before anyone says it, yes, there's not enough dust, I know.

Astro0

Posted by: briv1016 Jan 4 2009, 10:32 PM

According to the tracking site the Bonestall Pan is not fully downlinked yet?

Posted by: djellison Jan 4 2009, 10:38 PM

95% of it's down - and of the remaining 5% - it's mostly lower-tier fill in images.

Posted by: Ipparchus Jan 5 2009, 11:11 AM

I `d like to propose a route for Spirit, that I think, could possibly make her arrive to Goddard and Von Braun easier and faster. Spirit could drive down the slope she is on, then drive west following her old tracks and climb on the ramp she used on Sol 755 to arrive on Home Plate. After that, she could easily and fast drive on the good terrain of HP and arrive to the South edge where she could find a good ramp (a low-degree slope) to drive down and continue South until she reaches Goddard or Von Braun (the whole route is represented with a red line). Please, tell me your opinion about this proposed route. I would be grateful to have, also, a comment from Paolo, the Rover Driver! I`m sending you a new (my) version of the great post I found in the site. I hope you like it! Happy Birthday Spirit !!! Astonish us more times than you have done before!

Posted by: djellison Jan 5 2009, 11:13 AM

She did that with 6 wheel drive. She can't get up the slope she's on now with 5 wheel drive - I doubt she'd get up the 755 slope with it either.

Whilst straight over home plate would have been preferable - going the 'long way round' has benefits, a trench that will depict the distribution of more silica, if it's there, down one length of home plate will be interesting.

Posted by: PaulM Jan 5 2009, 12:48 PM

Now that Spirit is committed to backing off Home Plate, I think that Spirit should retrace its old route back to Lowe Ridge.

My reason for suggesting this is that a route already driven is guaranteed to contain no sand traps. My suggested route may be even safer than the originally planned route diagonally across Home Plate. As was demonstrated on Sol 1384 there are hidden sand traps even in the apparently solid ground on the top of Home Plate.

I understand that the safest way to escape from a mine field is to retrace your old footsteps. This is effectively what I am suggesting that Spirit should do.

Posted by: sci44 Jan 5 2009, 12:55 PM

With only 150W/h available, wont most of the driving be short hops mostly within the field of view for the Navcams/Pancams? Wouldn't that help avoid that danger? Unless there is a good reason, I would have thought it better to cover new ground..

Posted by: mhoward Jan 5 2009, 01:38 PM

The interesting question is, could she now make it up the slope slightly to the east? Hard to say.

Posted by: djellison Jan 5 2009, 02:56 PM

She did get onto Home Plate with 5WD after the Silica / Innocent Bystander etc. campaign

Doug

Posted by: mhoward Jan 5 2009, 03:05 PM

True, and I'd like to think she could make it. That said, a trip around to the west has some appeal, despite the lurking danger of getting stuck.

An anaglyph view east-ish:
http://flickr.com/photos/marscat/3148752988/sizes/l/

Posted by: BrianL Jan 5 2009, 06:29 PM

On the other side of the planet, there seems to be a high level of confidence that the purgatoids can be identified and avoided, or should embedding occur, that the rover can be easily extracted. Does that same confidence exist with Spirit's "purgatoids", such as Tyrone or Tartarus? Can areas of likely or even possible embedding due to the dragging wheel be identified before being driven into?

Also, why not put the stuck wheel in front? Would this not give earlier warning of increased resistance to movement while the driving wheels are still on fairly solid ground?

Posted by: djellison Jan 5 2009, 06:41 PM

Significant testing and experimentation shows that dragging is the better driving method.

Posted by: lyford Jan 5 2009, 06:48 PM

Plus, dragging the wheel behind gives it an http://www.youtube.com/watch?v=XaPZZJVDx6Y -

"Yes, MARSTER!"

Posted by: djellison Jan 5 2009, 07:17 PM

I tend to describe it as a puppy dragging a broken paw -it gets more 'awwwww' from an audience.

Posted by: ElkGroveDan Jan 5 2009, 08:55 PM

Stu's going to have fun with you over that one Doug. After all, it's just a machine.

Posted by: fredk Jan 5 2009, 09:13 PM

For a long time I've considered myself in the "if we can't get onto HP here, drive down and try to climb onto HP somewhere else" camp (is it actually a camp?!). As others have pointed out, we've done it before with five wheels, on sol 1306.

Remember why we chose this spot at the edge of HP for our winter haven: it had the steepest slope! So it's not surprizing it's hard to get up here. Almost anywhere else should be easier to climb onto HP. And there are spots that would be much easier.

I guess I'm driven by fear of getting bogged down in West Valley. Also it's a matter of time: a route over HP would be more likely to get us to von Braun/Goddard before a catastrophic failure.

Posted by: fredk Jan 5 2009, 09:18 PM

Isn't she getting a little long in the tooth to be a puppy?

Posted by: djellison Jan 5 2009, 09:54 PM

Steepest NORTH FACING slope.

Doug

Posted by: Stu Jan 5 2009, 10:21 PM

I use the puppy/broken paw image myself for "general" groups... for more spacey groups I compare it to "that little robot in SILENT RUNNING that has to walk with a limp..."



That usually gets a BIG "Awwwwwww!"

Posted by: CosmicRocker Jan 6 2009, 04:41 AM

If you are talking about the sol 768 location (the second place Spirit climbed onto Home Plate), I think it would be worth trying before going all the way to Silica Valley for an attempt. Even though Spirit had the use of all six wheels when she climbed up on sol 768, the slope appears to be moderate. Attached is a MMB anaglyph panorama of the approach showing the rover's track.

Posted by: peter59 Jan 7 2009, 08:55 AM

Finally a clear decision.
http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-01-07/2F284561238EFFAZ89P1212R0M1.JPG
http://qt.exploratorium.edu/mars/spirit/rear_hazcam/2009-01-07/2R284561290EFFAZ89P1313R0M1.JPG

Posted by: briv1016 Jan 7 2009, 01:39 PM

The real question now is what are our power levels now that where at a near zero tilt?

Posted by: Stu Jan 7 2009, 02:03 PM

On the move again...

Animation http://cumbriansky.files.wordpress.com/2009/01/animation2.gif.

Posted by: RoverDriver Jan 7 2009, 05:49 PM

We are at about 13 degrees tilt (10 deg northerly tilt), not flat. The values I have seen (~180Wh) are from sol 1782 which has peen party spent at 30 deg so it is not representative of the values we will have from now on. We have to be patient for a couple of days.

Paolo

Posted by: Sunspot Jan 7 2009, 06:18 PM

Judging by the deep shadows the sky looks like it must be quite clear.

Posted by: mhoward Jan 7 2009, 06:52 PM

http://planetary.org/blog/article/00001801/:

Just to get super-nitpicky, I think we may still be high up enough to see over Home Plate, just. Probably not for long, though.

Edit: I mean from the camera mast, obviously.

Posted by: brellis Jan 7 2009, 08:02 PM

Remember to look both ways before crossing the (sol 766) tracks!

Posted by: Tesheiner Jan 8 2009, 08:40 AM

Based on the imaging plan I would say East.

01784::p0665::03::10::0::0::10::0::20::navcam_5x1_az_108_3_bpp
01784::p0765::01::10::0::0::10::0::20::navcam_5x1_az_288_1_bpp

Posted by: RoverDriver Jan 8 2009, 03:37 PM

There is a potential passage about 7m to the east. It was seen on Sol 768 IIRC, it might be traversable. We'll see.

Paolo

Posted by: Ipparchus Jan 9 2009, 11:40 AM

Paolo, when is Spirit going to move again, east? What distance can she rove on each sol with the current watt/hour numbers ? Has the MER team got a plan to find a ramp and drive on HP?

Posted by: RoverDriver Jan 9 2009, 12:22 PM

All very good questions, for which I have no answers yet. There will be a pow-wow today discussing these issues but I will be on a MER-B shift today so I am not sure I will be able to attend. I will let you know if I hear anything.

Paolo

Posted by: mhoward Jan 9 2009, 03:44 PM

New Navcam pan for Sol 1784. Here once again is my http://mmb.unmannedspaceflight.com/MERA1784Navcam.mov (QuickTime 3.6 MB)

Posted by: Doc Jan 9 2009, 07:07 PM

And a panorama for quick browse.

The ground sure looks like its tilted towards the plains... watch your step

Posted by: Zvezdichko Jan 9 2009, 09:35 PM

http://qt.exploratorium.edu/mars/spirit/navcam/2009-01-09/2N284650783EFFAZ89P1914L0M1.JPG

I think that we have less dust than before. What do you think?

Posted by: djellison Jan 9 2009, 09:52 PM

In some places less, in some places more - I think we're seeing redistribution rather than clearance here.

Posted by: ElkGroveDan Jan 9 2009, 10:15 PM

But a good sign nonetheless. Now if we get a few more "redistribution" events it might redistribute some of the dust to the ground.

Posted by: djellison Jan 9 2009, 10:20 PM

Oh yeah. We're at 'cleaning time' in terms of season - we're less than 20m from the last SIGNIFICANT cleaning event location. All the signs are positive.

Doug

Posted by: CosmicRocker Jan 10 2009, 06:30 AM

I noticed a partial deck pan from sol 1783, so I thought I would do a quick stitch.

The result is a bit distorted for some reason, but interesting to study. It appears that there are several populations of dust, silt, and sand grains on the deck. I obviously cannot see the grains themselves, but I am hypothesizing (speculating) from the colors and patterns I see. We observe light, medium, and dark colored patches of sediment on the deck. There clearly has been a lot of moving and sorting of grains on the rover's horizontal surfaces over the past months. The wind-oriented fingers of sediment flowing around minor obstructions such as the bolt heads to the left of the mast are scary. That is some pretty heavy buildup, and without the aid of saltation, some of it might be pretty difficult to remove in typical "dust cleaning events."

Looking at this scene, I can't help but wonder if this WH3 location, below the very edge of HP has allowed larger saltating grains hopping across Home Plate's surface, to hop onto our desperate rover as it clung to its life-giving, north-facing slope all winter and into this spring. I guess I am not certain what the prevailing wind direction is here as the seasons change, so I probably shouldn't speculate about such things.

I suppose I should edit this post to note that the areas of the heaviest buildups are mostly away from the solar panels.

Posted by: Stu Jan 10 2009, 08:14 AM

http://cumbriansky.wordpress.com/2009/01/10/looking-back-up-at-homeplate... (3d pic)

Posted by: RoverDriver Jan 10 2009, 01:50 PM

We did not have much of a choice, unfortunately. :-( It is possible that the orientation of the rover could have caused additional deposition of particles, but no matter where we could have parked, the orientation of the rover would not have been significantly different relative to the direction of the prevailing winds. In addition, the rover deck was for a good portion at a higher elevation than HP. If saltation was really the process in play here, I am misunderstanding the scale of the height and length of the hops.

Paolo

Posted by: jamescanvin Jan 10 2009, 04:54 PM

The Bonestell pan is finally all down! here is my version.

http://www.nivnac.co.uk/mer/index.php/full_bonestell

And a Mars bar to the first person to spot what is missing from this pan that is in (I think) every other large 360 degree pan from the rovers.

James

Posted by: Stu Jan 10 2009, 05:31 PM

A plesiosaur..?

Seriously James, that is truly stunning.

Posted by: Tesheiner Jan 10 2009, 05:34 PM

The rover itself?

Posted by: mhoward Jan 10 2009, 05:49 PM

Probably the low-gain antenna (LGA)? It's out of the way because we're tilted at such an angle.

Posted by: djellison Jan 10 2009, 05:54 PM

Yup - the top of the LGA is in every other pan.

Posted by: jamescanvin Jan 10 2009, 06:00 PM

Yep, it was the LGA

Congrats Mike. I'm actually all out of Mars bars I'm afraid - would you accept a polar projection instead?

http://www.nivnac.co.uk/mer/index.php/full_bonestell

Posted by: ngunn Jan 10 2009, 10:09 PM

That's really beautiful James. I notice you've made the sky colour the same at both ends.

Posted by: Shaka Jan 10 2009, 11:51 PM

Sorry to bother people with my petty problems of computer iliteracy, but this image does not appear on my screen unless I switch off ZoneAlarm.
I already have the UMSF site designated a ZA favored site (with all green checkmarks - no red x's ), but I still don't see many images or animations (e.g. emoticons no longer animate ) Please don't advise me to discard ZoneAlarm - If it dosn't protect my machine, I have no ability to do so manually.
Is anyone out there able to co-exist happily with ZA? As of some weeks ago I cannot.
The wheel ain't goin' aroun' no more!

Posted by: mhoward Jan 11 2009, 12:17 AM

I don't deserve the Mars bar anyway - I had to Google the answer, since I can never remember which antenna is which.

Posted by: ElkGroveDan Jan 11 2009, 01:13 AM

I dunno Shaka, but I suspect there's probably a setting in there related to the level of caution to use when loading images. If you find it change it.

Or instead of ZA you could install Norton or McAfee which I have on several machines and my UMSF images always load fine with them.

Posted by: fredk Jan 11 2009, 02:45 AM

The polar projection thumbnail image that appears above in this thread is hosted on Canvin's site www.nivnac.co.uk, not here at UMSF. You could check that Canvin's site hasn't been blacklisted for some odd reason.

Posted by: briv1016 Jan 11 2009, 12:28 PM

James, the full res version is not working for me. (Red "x" of death.) The other 3 versions do.

Posted by: jamescanvin Jan 11 2009, 01:02 PM

They seem OK to me - maybe just a temporary glitch (my hosting sometimes is a little slow) try again.

Also the large image is VERY large - 153 MegaPixels. Some browsers assume that such large dimensions can't be true, and flag the image as corrupted. So you may want to try right clicking and choosing 'save linked file as...' instead.

Posted by: briv1016 Jan 11 2009, 03:06 PM

It worked. I had to save link to my documents. I guess IE didn't believe it's size.

Posted by: Oersted Jan 11 2009, 11:37 PM

For anti-virus I'd suggest freeware AVAST. Updates very often, very good.

http://www.avast.com/eng/avast_4_home.html

Posted by: djellison Jan 11 2009, 11:56 PM

Totally off topic for the thread and UMSF generally - but I will second a vote for AVAST. It's on my home desktop PC, and 6 machines at work. Touch wood - never had a problem, nor seen a significant performance impact when working.

Posted by: mcaplinger Jan 12 2009, 01:04 AM

Zonealarm and Avast are not the same sorts of thing: Zonealarm is an intrusion detection system that can see unauthorized traffic outbound from your machine; Avast is an antivirus program that as far as I know doesn't look at network traffic at all (at least the free version doesn't.) The two can be complementary.

Posted by: Astro0 Jan 12 2009, 03:08 AM

Meanwhile...back on- topic...

Any thoughts here? A noticeable darkening of images on Sol 1785 between 11.42 and 11.48 local time.
All navcam L0. 5 frames, the last two seem to darken. Illusion? Passing cloud?

Astro0

Posted by: fredk Jan 12 2009, 10:37 PM

We see similar things from time to time. I'd guess it has to do with the fact that these are subframes. Probably some portion of the rover was in the field of view, but has been cropped away now so you can't see it. As the series of images proceeded, the sun moved and by the end of the sequence there was perhaps a bright glint of sunlight off the rover part. That resulted in a shorter exposure for the final frames.

This can't be exactly right, since the jpegs we see are supposed to be autostretched. But if you look closely at the bottom of these frames, you can see a few rows of white pixels. So the autostretching isn't working properly - it's biased by those bright rows.

The real question is where do those white rows come from. I still suspect my description above is more or less right, and that the rows of white pixels are increasing in absolute brightness (before stretching) as the sequence proceeds, which would explain the darkened later frames.

Posted by: RoverDriver Jan 12 2009, 11:32 PM

Astro0, is this a readiometrically corrected image? If not, the autoexposure might be affected by areas outside the subframe. If Im not mistaken the autoexposure works on the entire frame, not just the subframe.

Paolo

Posted by: Astro0 Jan 13 2009, 03:01 AM

The images are just straight off the exploratorium site as delivered there. Stretched yes, altered in any other way(?), no.
I thought about it being some kind of reflective surface elsewhere lightening the earlier frames, but the frames only cover a period of 6 minutes - could there be that significant a change in that time? The dip in light levels seems consistent across the frame too.
I'm not suggesting anything here, just curious? The more technically minded among you will know the answer I'm sure. Fredk's response sounds right.

Astro0

Posted by: dvandorn Jan 13 2009, 05:30 AM

The one event that would explain a real "darkening event," it seems to me, would be the very close passage of a dust devil. (Or at least the passage of a dust devil between Spirit's immediate surroundings and the Sun -- i.e., in the DD's shadow.)

Anyone check the solar panels since that observation? Or the watt hours?

-the other Doug

Posted by: CosmicRocker Jan 13 2009, 05:39 AM

Apparently fredk had already suspected that, but, that is good to know. It hadn't occurred to me that the auto-stretch algorithm might be automatically applied to the full frame of a subframe image.

O'Doug: I suppose it could be a close encounter of one kind or another, but is this a fun place to hang out, or what?

I saw two earlier images from sols 1511 and 1517 come down today. For a moment I thought, "OMG, Spirit is almost on top of HP again.

Posted by: mhoward Jan 13 2009, 09:27 AM

I think he means the exposure duration that happens on the rover, not the brightness stretching that is applied to the JPG images we get online, CR. But then it seems like the brightness stretching should tend to hide that, so I don't know.

Posted by: RoverDriver Jan 13 2009, 09:39 AM

Yes, I mean the exposure setting is determined on board based on the full frame image. I have no idea what algorithm is used to do the 12->8 bit conversion. If it is just a scaling factor, it would not compensate correctly and if it is a full linear conversion, the algorithm might get fooled sometimes. Granted, the difference presented by Astro0 is quite large and am not sure if it can be explained this way. Mine is just a guess. I haven't heard anybody from Power screaming in joy or in terror. That might be a more reliable data point.

Paolo

Posted by: Stu Jan 13 2009, 05:23 PM

I love these "rock pile" shots... makes you want to reach into the screen and just grab one, doesn't it?

Posted by: Deimos Jan 13 2009, 09:27 PM

Hit the nail on the head. The white rows are related to electronics noise generated by the way "fast dust devil" subframes are generated. The rover uses the capability of the readout hardware to generate a subframe that is transfered into memory, rather than transferring a full frame and then cropping. This is faster, but has side affects at the readout end of the frame. The side affects are temperature dependent, and so increase with time as the electronics are used. The actual scene brightened very slightly over the sequence of images. Most of the frame is not affected, so cropping the bottom couple rows masks the effect (an old example is here: http://www.lpl.arizona.edu/~lemmon/mer_dd/dd_enhanced_1239a.gif).

These images didn't use the 12-->8 bit conversion (I think). So the electronics generated 12 bits, these were downlinked, and then a linear scaling was done (tossing the brightest 1% and darkest 1% of pixels, I suspect). If the 12-->8 scaling had been done on board, that would be non-linear--sort of like square root encoding with the most commonly used look up table. Also, since these images use hardware subframing, the autoexpose software never saw the rest of the frame--but it normally would. It was happy with a consistent exposure, allowing the fastest image acquisition.

Posted by: Oersted Jan 13 2009, 11:25 PM

Well, that sounds pretty authoritative to me

Posted by: fredk Jan 14 2009, 08:32 PM

Very good to hear all the subframing details; Thanks Deimos!

A few things worth mentioning in recent images. First, look not just at the rover deck, but at the ground in the foreground of this sol 1784 image:

http://marsrovers.jpl.nasa.gov/gallery/all/2/n/1784/2N284739208EFFAZ89P0665R0M1.JPG

To me it appears more mottled than usual (there's a high-contrast mix of lighter and darker patches). I think we're seeing the effect of wind clearing some patches on the ground. The ground in that new navcam reminds me of how the ground has looked after previous cleaning events, for example see this image from sol 424:

http://marsrovers.jpl.nasa.gov/gallery/all/2/n/424/2N164013816EFFA8B3P1705R0M1.JPG

or this image from 1250:

http://marsrovers.jpl.nasa.gov/gallery/all/2/n/1250/2N237338466EFFAUCMP1665R0M1.JPG

Either I'm starting to get a pretty good feel for how the Gusev ground should look, or I've been staring at Mars for too long!

And it looks like we've dug up some more of the tasty white stuff:

http://marsrovers.jpl.nasa.gov/gallery/all/2/p/1787/2P285005967EFFAZ89P2598L7M1.JPG

Posted by: jamescanvin Jan 15 2009, 03:09 PM

Finally got my computer to crunch out the full Bonestell pan in 3D colour.

Enjoy your stroll around - and try not to trip over any rocks.

http://www.nivnac.co.uk/mer/index.php/bonestell-anaglyph

James

Posted by: fredk Jan 15 2009, 04:00 PM

Thanks so much, James, that's absolutely stunning! It's also great to see real 3D, not the odd constant-depth anaglyphs we've seen recently from official channels.

Posted by: djellison Jan 15 2009, 05:23 PM

What do you mean? I've made a lot of them, viewed a lot of them, and I don't know what that means.

Posted by: fredk Jan 15 2009, 06:27 PM

Well, I don't know if there is a proper name for that style of anaglyph, but "constant-depth" seems to fit. Have a look at the recent official Bonestell stereo pan http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20081230a.html (I was looking at the "medium image" version.)

Look for example at the far right side of that stereo pan. The foreground surface and rocks appear set slightly back from the surface of your monitor. An easy way to see this is to place the mouse cursor at the patch of surface in question and then you can see that the surface in the foreground is slightly behind the mouse cursor.

Now, still on the far right side of that pan, do the same for Husband Hill. You'll see that Husband Hill appears at the same depth as the monitor surface. (You can also see this by noticing that the two colour channels line up for Husband Hill.) But the background/horizon should appear much farther back than the foreground! So in this case the depth is going the wrong way: in the official Bonestell stereo pan the foreground appears farther than the horizon, at least on the right side of the pan. Compare with James's stunning anaglyph pan.

You can see similar effects all over the official pan, and on other official pans. I believe what has been done to the official pans is that a shear has been introduced to one (or both) of the stereo channels to "flatten" the stereo effect over the range of distances from foreground to horizon. Think of what a bare, unprocessed anaglyph would look like that extends from nearby ground to the horizon. If you line the two channels up at the horizon, they get progressively out of alignment towards the foreground.

So you could imagine applying a shear to one frame, that leaves the horizon unchanged at the top, but progressively shifts the pixels to the right or left as you move down the frame to the foreground, in just such a way as to keep the two channels always (nearly) aligned. Then viewing the resulting anaglyph would be like looking perpendicularly at a wall. Of course small hills, rocks, ridges, dunes, etc would still stand out in 3D, since the shear you applied is smooth and gradual.

It looks like this is being done to official stereo pans. I would guess the reason is to make it easier to view a stereo pan that extends over a great range of depth, foreground to horizon. Basically you compress the "dynamic range" of depth greatly. Some people have a very hard time viewing anaglyphs and the more exteme the depth range the harder, I think. And, like I said, you can still see smaller features like ridges, rocks, etc in more or less proper 3D. But I don't like the result!

Sorry about the longwinded response - you can see why I didn't give any details in my previous post!

Posted by: djellison Jan 15 2009, 07:43 PM

Ahh - I get what you mean. I got around it when I was doing lots of anaglyphs by co-registering in the middle-ground - but even then, the channels were so seperated at near and far distance, they effect was lost. By 'moderating' the effect, you can, I suspect, get more effect over a greater range, but I can see why some people would like the 'raw and uncut' flavour of anaglyph instead.

You could use MMB - the anaglyphs are au-naturelle in there

Posted by: mhoward Jan 15 2009, 08:00 PM

That's a charitable way of describing it. "Minimalistic" might be accurate as well.

Posted by: Oersted Jan 16 2009, 01:41 AM

What a beauty, but could we have it stretched out properly, i.e. flat and tidy?

Posted by: djellison Jan 16 2009, 02:34 AM

Spirit wasn't

Posted by: jamescanvin Jan 16 2009, 08:49 AM

Exactly. For the best 3D effect the way your eyes look at the anaglyph should be the same as when Spirit looked at it, by keeping it this way it means you don't have to tilt your head or put up with strange distortions. .

I do have both the left and right colour pans made with a flat horizon, so I may try and put them together and see how the it looks when I get the chance.

Posted by: Tesheiner Jan 16 2009, 01:00 PM

FWIW, today was a driving sol. Expect pictures from the new site in the next downlink session.

01791::p0685::03::10::0::0::10::0::20::navcam_5x1_az_144_3_bpp
01791::p1206::04::2::0::0::2::0::4::front_hazcam_half_bpp_pri_56
01791::p1214::05::2::0::0::2::0::4::front_hazcam_ultimate_4_bpp
01791::p1306::02::2::0::0::2::0::4::rear_hazcam_half_bpp_pri_56
01791::p1313::02::2::0::0::2::0::4::rear_haz_ultimate_3bpp_pri15

Posted by: Oersted Jan 16 2009, 01:35 PM

Our dear Spirit doesn´t have the ankle joint of any field geologist who would have stood in her place, upright, parallel to the gravity vector. I'd like to see the view that field geologist would have had...

I tried fooling around with the half-size version of the panorama in Photoshop (tilting it vertically, then using the "shear" filter, then turning it back to horizontal again). I actually thought it quite pleasant to look at with red-green glasses, the flat horizon was beautiful. Only concession was that it was necessary to tilt my head a bit at times, to get the 3D-effect to click into place. But that felt like a small concession for getting an undistorted pan. Probably not acceptable to casual viewers, but for "pro image peepers" it works, even at the price of a bit of dizziness.

My woeful PS job was so bad that I didn't want to upload it, I hope some of our fantastic image pro's can do it better.

Posted by: jamescanvin Jan 17 2009, 04:48 PM

Just for you Oersted.

Flat horizon version, seems to work quite well generally, but there a re a few areas that don't work well. Don't complain to me when it gives you a headache.

http://www.nivnac.co.uk/mer/index.php/bonestell_anaglyph_flat

And here are the images taken after the drive off HP looking back at the slide. Loving all those disturbed rocks caused by all that trying to get up on top.

http://www.nivnac.co.uk/mer/index.php/1788

James

Posted by: ElkGroveDan Jan 17 2009, 05:19 PM

What? No polar version? Where's Phil Stooke when we need him?

Posted by: Tesheiner Jan 17 2009, 05:32 PM

He is at the http://www.unmannedspaceflight.com/index.php?s=&showtopic=5702&view=findpost&p=134300.

Posted by: mhoward Jan 17 2009, 07:14 PM

Here's a short movie flying by the depression just to the north east, where Spirit might possibly make it back up onto Home Plate. The empty area is where Spirit is currently located, more or less.

http://mmb.unmannedspaceflight.com/HomePlateBump_s.mov

Posted by: jekbradbury Jan 17 2009, 07:49 PM

Wow! How did you make that movie? That looks sort of like MER3DSiteViewer from the "My Personal Mars Rover 3D Program" thread, but I could never make it look like that.

Posted by: mhoward Jan 17 2009, 07:54 PM

It's generated from the rover 3D data as a programming experiment, and recorded off my Mac using "iShowU". Uses basically the same data as the MER3DSiteViewer, I imagine.

Posted by: Phil Stooke Jan 17 2009, 08:05 PM

Gimme a break, I can't be everywhere.

Phil

Posted by: djellison Jan 17 2009, 08:32 PM

Wouldn't a polar-anaglyph be, just, err, wrong? it would be inside out at the bottom, I think.

And James, being the thorough chap that he is, did do the non anaglyphy version http://www.nivnac.co.uk/mer/index.php/full_bonestell

Posted by: ElkGroveDan Jan 17 2009, 08:56 PM

Probably best viewed while listening to Pink Floyd.

Posted by: ngunn Jan 17 2009, 09:07 PM

A visual abomination! It hurts my head to think about it. An endless cylindrical version from AndyG - now that would be another matter.

Posted by: nprev Jan 17 2009, 11:02 PM

Dammit, now I wanna see it.

Posted by: djellison Jan 17 2009, 11:14 PM

Just turn your glasses inside out to look at the ends of the anaglyph.

Posted by: Oersted Jan 18 2009, 12:24 PM

Thanks, I like that one a lot, headache and all. I guess it would be theoretically possible to shift and turn the red-green version around a bit to make them line up differently and so give us a head-ache-free version. If that could be automated it would be amazing, because manually it must be nigh impossible.




Oh I love those too, she really thrashed the place!

- Thanks so much for posting!

Posted by: AndyG Jan 18 2009, 06:56 PM

Something like http://personal.strath.ac.uk/andrew.goddard/bonestellpan.html?

It's a rather fat 3.9M, and uses James' wonderful quarter-resolution panorama. Whose ends, I must add, match perfectly, both on ground in in that gorgeous sky. Many thanks for providing the source, James.

There's a few tweaks I want to do with it, but please "take her for a spin".

Andy

Posted by: ngunn Jan 18 2009, 07:11 PM

Posted by: HughFromAlice Jan 18 2009, 08:33 PM

Good one!!!!!!!!

Posted by: peter59 Jan 18 2009, 09:01 PM

01793 p1206.04 0 0 0 0 0 0 front_hazcam_half_bpp_pri_56
01793 p1206.04 0 0 0 0 0 0 front_hazcam_half_bpp_pri_56
01793 p1214.05 0 0 0 0 0 0 front_hazcam_ultimate_4_bpp
01793 p1214.05 0 0 0 0 0 0 front_hazcam_ultimate_4_bpp
01793 p1306.02 0 0 0 0 0 0 rear_hazcam_half_bpp_pri_56
01793 p1306.02 0 0 0 0 0 0 rear_hazcam_half_bpp_pri_56
01793 p1313.02 0 0 0 0 0 0 rear_haz_ultimate_3bpp_pri15
01793 p1313.02 0 0 0 0 0 0 rear_haz_ultimate_3bpp_pri15

Next scheduled drive (sol 1793) and again nothing. Slowly I lose faith that we'll see closely von Braun and Goddard.

Posted by: BrianL Jan 18 2009, 09:28 PM

I'm not losing faith just yet, but it would be nice to know what's going on.

Posted by: Tesheiner Jan 18 2009, 10:05 PM

There were no data from any sol downlinked today, so it might be too early to say if the driving sequences were executed or not.

Posted by: Tesheiner Jan 19 2009, 09:06 PM

No data yesterday ... and also no data downlinked today (sol 1794).

Posted by: alan Jan 19 2009, 09:12 PM

Until recently they were on a work one day/recharge two days schedule due to the limited energy. Maybe this is more of the same.

Posted by: RoverDriver Jan 19 2009, 10:03 PM

The drive should have executed on 1793 but data will not be downlinked until 1795 (Tuesday morning PST). I'm in the dark just as you are.

Paolo

Posted by: fredk Jan 20 2009, 04:02 PM

The radio-frequency light has arrived:

http://qt.exploratorium.edu/mars/spirit/forward_hazcam/2009-01-20/2F285540312EFFAZAFP1206L0M1.JPG

Posted by: peter59 Jan 20 2009, 04:39 PM

Spirit, where you are going?
Whether Spirit wants to climb again on the Home Plate ? http://qt.exploratorium.edu/mars/spirit/navcam/2009-01-20/2N285540587EFFAZAQP0685R0M1.JPG it is probably possible.

Posted by: Tesheiner Jan 20 2009, 05:34 PM

Here's a navcam mosaic.

Posted by: mhoward Jan 20 2009, 05:51 PM

Here's a view with the rover model in Spirit's previous position. The placement may not be 100% perfect, but it may give a sense of scale.

http://www.flickr.com/photos/marscat/3212484603/sizes/l/

Posted by: centsworth_II Jan 20 2009, 06:10 PM

It's easy to see in that image that Spirit was parked in the worst spot to try to mount Home Plate.

Posted by: Stu Jan 21 2009, 10:44 AM

Quite a drop off Homeplate...

Posted by: nprev Jan 21 2009, 12:13 PM

...you ain't kidding! That has "high-centered" written all over it.

Posted by: mhoward Jan 21 2009, 10:48 PM

She's looking at the ground with the MI now. And the previous Pancam of the churned up wheel track was labelled "Thunderbolt". A new discovery by the Persistent Trenching Tool, perhaps? Just speculating.

Posted by: fredk Jan 22 2009, 03:07 PM

From http://www.planetary.org/blog/article/00001816/

That doesn't surprize me with power levels as low as they are now. I would think that should give enough time to drive to Goddard/von Braun, if the drive goes relatively smoothly. Of course a nice strong gust of wind would always be welcome...

Posted by: Stu Jan 22 2009, 07:25 PM

That's another nice trench you've dug for us, Spirit...

Posted by: djellison Jan 23 2009, 09:03 PM

ANOTHER drive - time for a new thread