Need more technically advanced FAQ/tutorial/feedback

Discuss your experiences with and ideas about Stardust@home here.

Moderators: Stardust@home Team, DustMods

mdiehl
Posts: 11
Joined: Thu Aug 03, 2006 10:30 am

Need more technically advanced FAQ/tutorial/feedback

Post by mdiehl »

I suspect there just might be guys or gals participating in this experiment who actually have years of lab experience and who have spent many hours becoming bleary-eyed behind many sorts of microscopes. As a guy at the incredibly old age of 51 with experience in Microscopy, some of these excercises get a little frustrating because although we know in general what we're looking for, we have a thousand questions we'd like answered from the researchers and particularly the techs who have nearly permanet circles around their eyes from the rubber eye-guards/shades! I'm pretty sure most of us are treating each "movie" as a "real" sample and trying to extract data from it the best way we can.

Call me a grumpy old crumudgeon, but back at the engineering labs we could at least ask question from the engineers and did have our ways of dealing with kids.......
Nikita
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Post by Nikita »

Usually the engineers knew what they were working with though. Our peepers are the first to view these, so until we point it out for them to look at, they have no idea what is there. I had one film that had some junk on it that looked like a lobster! I agree it would be nice to get the feedback, perhaps once they get a chance to look at the ones we flag, they'll let us know what it was.
It still has me awed to think that we are looking at stuff from space! And who wouldn't want to do this?!? :D

Good luck Mdiehl, I hope your dusting goes well and some day we get our answers!
From dust we come
leggat
Posts: 10
Joined: Tue Aug 01, 2006 8:24 am
Location: Rochester, NY

Post by leggat »

I have a similar request, one not answered through email. I haven't been able to answer any of my questions through the noise on the forum anyhow, but I'll ask them here now that my account is activated. Is there a page on the forum or some way you'd be able to describe the initial characterization techniques? Even a sanitized P.R. version.

Is it strictly optical microscopy, since charging would be a beast in S.E.M.? Done in a dry atmosphere?

Any use of dual polarizers to potentially observed stress induced birefringence at track sites?
Surface cracks may have them, or the stresses there may have relaxed over the years, but if there is any birefringence to be seen at all, I imagine that it will be surround a track where the stresses induced locally could still be present, unless those tracks collapse. Not to mention the stresses potentially present in the immediate vicinity of particles at a trails end.

I imagine samples of the collector aerogel material were characterized ten years ago before launch? B.E.T. (porosity, surface area), composition, skeletal&envelope densities, spectroscopy? These techniques will be interesting to follow up with. Backscatter mode SEM could show some interesting bits, and T.E.M. will eventually be a blast. I'd love an image of that.


Just a few questions, and if anyone could answer or link to some answers, I'd be grateful. I did the right thing and tried to search answers here, (1)the only post that had any mention of microscopy was this one, and (2) there is a time delay forced between searches.

Mdiehl, I know how you feel.
Wolter
DustMod
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Location: Enkhuizen, the Netherlands

Post by Wolter »

It seems to me that the questions posted here are a bit over the top. You might read the about Stardust@Home page once more to see what this is all about. We are here to assist in finding tracks which are hopefully made by stardust in the collectorgel. That's it.
Queries on how to so, problems with the VM and certain movies are adressed and answered when possible.

You can have a look at http://stardust.jpl.nasa.gov when you want to know a little bit more about the science behind it.

Queries going to a level that leggat posts here are way beyond the scope of the Stardust@Home project itself.
I agree it would be nice to gain that insite knowledge but i don't think it's fair to expect the team to provide answers to these kind of questions instantly.

Besides that the forum is currently swamped with questions, most of which are refrases of earlier posted and often answered questions. This does not only affect your abillity to find answers but also the teams abillity to find relevant questions...

My advise, take it easy, search the movies based on the advise from the tutorial and report them to the best of your abillity. Realise we are the helping hand (or eye's to be precise) just doing the tedious work.

Happy hunting
Just dusting... Image
petterip
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Joined: Sun Aug 06, 2006 1:12 pm
Location: Finland

Post by petterip »

...and if a further link is needed, there's a page of "science-in-depth" at the beforementioned JPL website. I think I'll read it through, too :wink: Thanks, Wolter :D
While not stardusting, I'd rather be driving with my Alfa.
leggat
Posts: 10
Joined: Tue Aug 01, 2006 8:24 am
Location: Rochester, NY

Post by leggat »

Awesome, I would like this added to the FAQ, even if no one else has the same urges, ;)
icebike

Post by icebike »

leggat wrote:
Any use of dual polarizers to potentially observed stress induced birefringence at track sites?
Surface cracks may have them, or the stresses there may have relaxed over the years, but if there is any birefringence to be seen at all .....
IBHE. (Interesting, but hardly essential).

[me: dons curmudgeon cap]

You either see it or you don't. Work with THAT!

For the purposes of this project this level of detail is not important. This project is not only hoping to find the tracks leading to particles, but also to assess whether this is a reasonable method to search for them, in short, can a million monkeys (us) really do useful scientific investigation given a simple task and a simple tool.

There are those of us who are interested in the microscopy, or the areogel, or the server network, or the php scripting, or the statistical analysis, or the scoring, or the database, the data elements collected or the future application of this unique approach, and several dozen more areas of inquiry, and the permutations and combinations three-of.

But how much can we really expect to be given? After all, to answer all these questions and the follow-on questions would take years, and make huge demands on the (expensive) time of the senior project staff.

Eventually, all this info could find its way to the web site, but these forums are not the place.

We volunteered for this project knowing that we were never going to get all the answers, and that our task was clearly laid out for use - look for these elements in these movies.

Now we see people (with the best intentions in the world) wanting to redesign the screens, the scoring, the actual content of the urls, the timing of movie delivery, the programming languages used, the color of buttons, ... the list goes on and on. They would repaint the launch vehicle if given the chance.

People lose track of the task at hand, picking at nits, and quarter-backing from the sidelines.

We have to work with what we have. It is what it is.

It works very well, its very cleverly built.

Its not perfect. We just have to deal with it, and wait for the published article in Scientific American or whatever.

I'm not sure I want my tax dollars spent by having highly paid scientists (and lowly dustmods) saddled with answering a hundred hen-pecking questions from thousands of users who are probably not qualified the evaluate the answers even if they knew them.

I'm satisfied to Click it if I see it, and click no-track If I don't.

[ end rant mode ]
[ climbs back into cave ]
Snoopy
Posts: 9
Joined: Sun Aug 06, 2006 3:06 pm
Location: Germany

Post by Snoopy »

come down icebike, they at NASA are just not better monkeys then we all are.
It's true we're doing this because we wan't to and no one ever promised kinda return for us, BUT they wouldn't be able to do this project in the nearby future AT ALL, if we all wouldn't lend them a hand.
So where's the prob for one of them to sit down several hours and answer some of the questions (o.k., reasonable ones) and spent some time on us? Answering questions in a way that they are well understandable in a simplified way even if they do cover complex issues shouldn't be a prob if they wan't to call themselves scientists.

If they waste all their time looking through flagged movies then something is going wrong here, because WE ought to find the particles and they just should lean back until we found them. Otherwise forget about stardust.

I don't expect them to answer at once of course, but it's part of the project to maintain the communication and give us some sugar.

If this fails, maybe they manage to train ants looking for stardust :twisted:
leggat
Posts: 10
Joined: Tue Aug 01, 2006 8:24 am
Location: Rochester, NY

Post by leggat »

Actually, lose the curmudgeon's cap, oh, and, SDEWSIA (some day everyone will speak in acronym).
The link posted by Petterip is exactly what I was looking for.

Interesting but hardly essential? And this entire project could not be described by the exact same phrase by someone a bit more smug and curmudgeonly than thou?
[quote= icebike]We volunteered for this project knowing that we were never going to get all the answers, and that our task was clearly laid out for use - look for these elements in these movies. [/quote] Speak for yourself, once they went into space on NASA's tab, an american citizen has the privelege and responsibility to seek every answer they have a question for.

And regarding their publishing in Scientific American? I thought I was dissappointed in the initial launch bottleneck last week, but you're downright malevolent. Wow, whether through your sheer curmudgeonly expertise at being a curmudgeon, or by a completely sloven accident, you essentially compared my post to hen-pecking and un qualified drivel. Never once did I nit pick or quarter back, I asked, and I might add without demanding answers in my own terms.

Having only contributed to three different publications on aerogels, I may very well have to agree with your ever so keen and curmudgeonly assesssing of my above post. Thank you for so cleverly and curmudgeonly dismissing me, IceBike!

Curmudgeonly!

Long, J. W.; Logan, M. S.; Carpenter, E. E.; Rolison, D. R. J. Non-Cryst. Solids 2004, in the press.

E.E. Carpenter, J.W. Long, D.R. Rolison, M.S. Logan, K. Pettigrew, R.M. Stroud, L.T. Kuhn, B.R. Hansen, and S. Mørup: "Magnetic and Mössbauer spectroscopy studies of nanocrystalline iron oxide aerogels", J. Appl. Phys, in press. 2006

J.W. Long, M.S. Logan, C.P. Rhodes, E.E. Carpenter, R.M. Stroud, and D.R. Rolison J. Am. Chem. Soc., 126 (51), 16879 -16889, 2004.

cheers Snoopy, and come down indeed, icebike.
meckano
Posts: 3
Joined: Tue Aug 08, 2006 6:58 am

Post by meckano »

couple points,
1) They should state the obvious in the tutorial: Don't concentrate on the specs to find tracks, look between them.
2) I had no idea we had to click exactly on the track, started off thinking we were yes/no 'ing a movie.

3) for slanted surfaces, in the futur they maybe should split a given slide into focus ranges and put a name suffix tag, ex:

(name)T1-2
would mean only check the highest half that comes into focus,
(name)T3-4
would mean check the 3rd from highest part of 4 that comes into focus.

- and they could maybe put more specific button choices now, like:

edit
1,2,3, or 4 (instead of just 'bad focus');
and we'd click how many parts we think it should be split into.
and 'need more depth' / 'need more height'
icebike

Post by icebike »

leggat wrote:
Having only contributed to three different publications on aerogels, I may very well have to agree with your ever so keen and curmudgeonly assesssing of my above post. Thank you for so cleverly and curmudgeonly dismissing me, IceBike!

Curmudgeonly!
Well, at least you didn't take it personally *cough*. :D

My point was this: would knowing the answers to your questions help Ma and Pa Polyester (not to mention Ivan Icebike) find tracks in these movies?

What percent of us (besides yourself) would even have the faintest idea of what your question meant, or what their answers imply?

Would it take longer for the Nasa/Berkeley people to find all the dust tracks themselves or to educate every volunteer to the point where they could understand both your question and the answers?

I sort of feel like a basketball player recruited to help search for a contact lense on the gym floor at an interrupted game. (Remember when that use to happen?). I'm not sure a lesson in optometry or the construction of wood basketball floors would be helpful.
leggat
Posts: 10
Joined: Tue Aug 01, 2006 8:24 am
Location: Rochester, NY

Post by leggat »

Actually, I just enjoyed writing curmudgeonly over and over again. The bit about observing stress induced birefringence might be a double edged sword anyhow. When we look into our virtual microscope, we see what a person would see in a real microscope, albeit at integrated images. This image is not black and white, but under the lighting conditions it appears so. [caveat:] They may have compiled the images in a black and white format, but for now, let's consider if they did not. [/caveat] Another piece of information is exactly how much more info a color image means across the internet. Probably a lot, but if they are not stored in a black&white format, they may be bigger image files when they perhaps could be smaller.

Now, birefringence, be it stressed induced or not, is observable in a material through fully crossed polarizers placed on either side of that material. Ordinarily, when you look through crossed polarizers, you get a whole lot of nothing, the first polarizer takes 50% of the available light away, and only of one direction of the light, say, the vertical component. You are left with the horizontal component, and since the second polarizer, (the analyzer) is rotated 50 degrees with regard to the first one, well, the light between them will be out of line with the analyzer, and poof, it's gone dark.

When you have a material with birefringence it means that it has 2 separate indices of refraction, or in plain words, it will bend light in two different ways depending on how the light interacts with that material's unique structure. Think calcite. Between to crossed polarizers, some of the light from the first polarizer will be twisted, and will no longer be cancelled out.

Now glass, be it window glass, or the silica aerogels we're peeping at, are preferably stress free before they enter a service environment, be that your living room, or the far reaches of space. Materials with no inherent birefringence can display birefringence when they are put under mechanical stress. The locales of differing stress levels coincide with locales of different indices of refraction, and so we can see, and in astonishing color displays, where in a sample a stress has been induced.

Aerogel before launch: mostly stress free
Aerogel after recovery: not quite as stress free, due to interactions with the space environment.

What kind of interactions? Star Dust. When they impact and tunnel in to the surface, they induce a stress due to the bonds being broken along the way, as well as at the point where they come to rest, where stresses may be greater.

These stresses may relax, bonds may break and reform, essentially allowing the body of the material to heal, and then there is the fact that the surfaces of the samples may appear incredibly dazzling, near locations of significant fracture of the aerogel, may . So it could be a double edged sword for us end users, due to too much color being distracting, and too large to move through the e-ether. But, I would bet a dust particle that they will at least give it a shot when it comes to confirming our potential finds.

Saying it without the technical terms can use less words, and icebike, thanks for not being too offended at my being offended :oops:
KarMann
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Location: Milwaukee, WI, USA
Contact:

Post by KarMann »

It seems to me, though, that given the exceedingly porous nature of the aerogel, what you'd get from an impact, at a very fine level, would be lots of little clumps of silica smashed and melted, but very little of that energy transferred as stress to silica that remains more or less in place (pardon the technical jargon :wink: ). And correct me if I'm wrong, but I don't think melted silica would display the stress birefringence, would it? And smashed but not melted bits wouldn't give a consistent pattern like a normal stress would.
I would refer to the Berkeley Lab page on the peculiar manner of absorption of kinetic energy by aerogels, but that site seems to be down at the moment. :( But you could try again later, of course.
Let it never be said that your **** retentive attention to detail never yielded positive results. - Loki, Dogma
icebike

Post by icebike »

KarMann wrote:It seems to me, though, that given the exceedingly porous nature of the aerogel, what you'd get from an impact, at a very fine level, would be lots of little clumps of silica smashed and melted, but very little of that energy transferred as stress to silica that remains more or less in place
How can you impart enough energy to melt it without also imparting stress?
Is areogel resiliant enough to bounce back from an impact and erease all stress stored in its structure?

Along that line of questioning, has anyone flown aerogel as a particle collector in space prior to this? I'm not aware of it if so.

Areogel must have some internal pressure and even air entrapment at manufacture right? So in space, does it degas? If impacted while in a vacuum would any stress marks induced be overwhelmed by the return to atmospheric pressure?
Nikita
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Post by Nikita »

To slightly modify IceBikes signature:

There are two different types of people, those who understand what in the world you just said, and ones that don't!

Got the basic idea, but you guys really know what you are talking about! Personally, I can tell you what happens when a baseball is thrown into my swimming pool, and into my window. :( After that, I'd have to go to bugs on my windshield.

Thanks for keeping it cool! Enjoy the new movies!
From dust we come
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