[X] My Assistant

[fredk]

the dust in the atmosphere is pretty thick.

Yeah. Ironically, it may be the same dust that makes the 2001 morning pan so stunning. At first I thought that was done before sunrise, since the shadows were so indistinct. But the sun was actually up for that sequence.

[HughFromAlice]

Here's the colourized version of the sunset - I have been enjoying putting this together so I hadn't really noticed the haze that much. But it does look like it's thick on the horizon. I've just read the Spirit update.

[Tman]

Hi, long ago since I've posted. Not much done in the old "hobby" but on and off a loyal looker here. Amazing the rovers still are aktiv and soon both beyond 2000!

Don't know was turned the balance but suddenly I was up for a try on the new lovely sunset from Spirit.
The time is in LTST ...and the coloring barely accurate, I guess.
Hoping you have fun with it as well as I had/have, in what respects could it be more accurate maybe?
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[HughFromAlice]

new lovely sunset .......... in what respects could it be more accurate maybe?

Nice one Peter (Tman)! Really glad that you posted. Watched yours a few times and learned some good things! Nice smooth sky + putting the times in.

I really pushed my interpretation, so that I think that the light part of the sky could 'flare out' and go a bit purple on some monitors. But, I was fascinated by the hills!! Your work has encouraged me to think more and (when I get time) improve what I've done.

Accuracy - only best eye guess using the screens of my PC! I have been thinking about true colour, but I've only just started thinking about it ---- also, so many different monitors,browsers and applications giving rise to so many very different viewing experiences.

[CosmicRocker]

Jumping to conclusions? ...

OK, I'll admit that to some degree, I am "jumping to conclusions," but I am also trying to read between the lines with the available information. I understand that we don't like to be too negative here, but at some point we have to start facing the facts. My interpretation may be totally off base, but I am trying to view the situation realistically.

We have many reasons to be optimistic as the tests with the light rover begin. I also look forward to the planned, long-drive tests which have apparently been delayed until after the light tests have concluded. The long-drive tests will be the acid tests for this rover. The people operating these machines are the best our planet has to offer, so I am certain that if anyone can extract Spirit from this pit, they will be able to. All I was trying to suggest is that the previous month's worth of testing must not have provided a clear escape route, hence, a new set of tests with the lighter rover is called for.

[ElkGroveDan]

All I was trying to suggest is that the previous month's worth of testing must not have provided a clear escape route, hence, a new set of tests with the lighter rover is called for.

Did you consider that the plan all along might have been to test the snot out of the instrument laden rover for a month or more, and then when a solution was found they would run through the entire process again with the lighter rover? In fact if anyone were to ask me I'd add a third round where the lighter rover would be tested on a lighter weight or less dense soil.

[Tman]

I have been thinking about true colour, but I've only just started thinking about it

It's still guessing, I think. Difficult to guess the color with the indirect infos we get and shifting lighting conditions make it even harder. On Mars we get a much thinner Atmosphere with more dust in it (that should scatter blue light around the sun like the "blue" moon here) and the sun is less bright over a reddish environment.

Speaking of dust, hopefully too the now more amount of dust in the air will not hit (too much). Power is needed whether she get out here or have to stay through the winter - however it seems to be a good place for cleaning events here.

[BrianL]

Did you consider that the plan all along might have been to test the snot out of the instrument laden rover for a month or more, and then when a solution was found they would run through the entire process again with the lighter rover? In fact if anyone were to ask me I'd add a third round where the lighter rover would be tested on a lighter weight or less dense soil.

Going back to Paolo's comments in June, there seems to be a need to "match" the test bed to the soil mixture to replicate the behaviour being exhibited on Mars. Given that, I'm unclear as to how putting TeeBee Lite into the same soil as TeeBee would better simulate what Spirit might do given the same commands. I hope Paolo can come back and shed some light on this.

[elakdawalla]

I was wondering the same thing. (And also wondering why Paolo hasn't been around -- apart from the obvious possibility that maybe he's just really busy.)

[ElkGroveDan]

I'm unclear as to how putting TeeBee Lite into the same soil as TeeBee would better simulate what Spirit might do given the same commands.

They are trying to replicate the "behavior" of the rover as it became embedded in the soil since they can never duplicate the actual conditions. If they had a few tons of the exact same soil in Pasadena it wouldn't do them much good because the soil itself would be 2.6 times as heavy as it is on Mars and therefore more compact with different mechanical properties (and that doesn't take into account whatever effect the 100 times atmospheric pressure might have on the soil properties). It's not possible to recreate those conditions so they are instead using trial and error to create conditions where the test rover behaves as the one on Mars did when it got stuck. Once they do that there is an assumption that the rover behavior in the extrication process worked out in Pasadena will likewise be duplicated on Mars,

Paolo mentioned that this is what they did with purgatory. At first they tried the rover that weighed 38% of the actual rover, assuming it would behave the same as the rover on Mars was behaving. But it did not. They couldn't get the lighter rover to embed itself in the test dune the way the real rover did at Purgatory. So they switched to the heavier rover and a different soil mix and eventually they achieved an analogous ratio of rover mass to soil density that worked in the test bed. But you have to remember that analogous relationship worked at that place at that time with those mixtures. The situation at Gusev is far different. So they are touching all their bases with the lighter rover just to be certain that some disastrous consequence might not come from whatever they have planned.

I personally am still in favor of them researching some exotic mixture of terrestrial materials to create an extremely light mixture for the testbed as the final test with the stripped down rover.

[nprev]

(also wondering why Paolo hasn't been around -- apart from the obvious possibility that maybe he's just really busy.)

Me too. Seems like the testing is really in high gear right now, so I'm betting on the obvious possibility. IIRC, he was running this show.

[Fran Ontanaya]

an extremely light mixture for the testbed

Aerogel. It can't get lighter than that. Funny thing is that Spirit is carrying some as insulator.

[CosmicRocker]

Did you consider that the plan all along might have been to test the snot out of the instrument laden rover for a month or more, and then when a solution was found they would run through the entire process again with the lighter rover?

No, I honestly didn't consider that, Dan, because I doubt that was the plan from the beginning. With problems like this one can never know how the testing will turn out, so they must proceed one step at a time. I'm sure if the initial tests went extremely well there would have been a few follow-up tests to be certain, and then they would probably have begun extraction maneuvers on Mars.

I suppose the cleaning events in early July would have removed a lot of pressure to rush things, and perhaps encourage more extensive testing. Anyway, I'm not trying to convince anyone that my hunch was correct. I'm sure everyone can come to their own conclusions about the SSTB-lite testing.

[djellison]

There is a difference between the testing going badly (i.e. no extraction) and the testing going well ( i.e. extraction) but not replicating the vehicle dynamics as best as they think they can.

That's what they've got to do - get the ISIL to match Gusev as well as possible.

[MahFL]

That sunset, from yesterday...is really amazing.