Should we still flag likely inclusions?

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Alessandro Freda
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Joined: Fri Aug 04, 2006 12:12 pm
Location: Genoa, Italy
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questions about the inclusions

Post by Alessandro Freda »

I've a doubt .... what are the inclusions ?
I think that are dust(?) particles inside the aerogel when it was made, is this correct ?
If yes, the nature of these particles will be always "not extraterrestrial" ?
If yes, after seen many inclusions I think to be able to identify them, because the shape of their intra-extra focal image is identical to the dust particles ones on the aerogel surface, when both are in a flat field ( = not superimposed to any kind of object).
If all this is correct, is it useful to continue to click on these kind of traces, or we should start to skip in order to try to reduce the job amount of the stardust team ?

An other question:
reading at my events log I see that some kind of tracks (in my opinion candidate to be inclusions) shown many agreements by other users, but someone very few, or only 1. The tracks with few agreements will be ignored at all ?
Since the last kind of tracks seem to be of 2 types:
1) very very faint
2) the movie do not reach the focus on the particle
is it useful to continue to submit these kind of traces ?

Regards
Alessandro

DiamondGirl
Posts: 77
Joined: Tue Jun 13, 2006 12:16 pm
Location: Syracuse, NY

Re: questions about the inclusions

Post by DiamondGirl »

Alessandro Freda wrote:I've a doubt .... what are the inclusions ?
I think that are dust(?) particles inside the aerogel when it was made, is this correct ?
Wow - great question! I'll be interested to see what the technical answer is.

I'm a big jewelry person, so I always think of "inclusions" as the term is used when thinking about gem stones. They're just natural flaws in the material you're looking at.
Alessandro Freda wrote:If all this is correct, is it useful to continue to click on these kind of traces, or we should start to skip in order to try to reduce the job amount of the stardust team ?
I'm glad you asked this. I remember seeing someone quote an early post from the home team saying that if you saw anything, no matter how small, to click it. Later some of these inclusion slides ended up causing me to get scored incorrectly, so I modified my strategy and started marking them "bad focus" slides. Now that we're further along, I'm eager to hear what the mods would prefer us to do, since most of us have found a way to identify these inclusion type particles from other types of marks.

--DiamondGirl

fjgiie
DustMod
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Location: Hampton, SC, US

inclusions

Post by fjgiie »

Hi Alessandro Freda,
Alessandro Freda wrote:If all this is correct, is it useful to continue to click on these kind of traces, or we should start to skip in order to try to reduce the job amount of the stardust team ?
Official word on inclusions comes from Dr. Butterworth in an Update: "Latest Findings: Movie Reviews"where she says
"Movie 714410V1 is an example of multiple tiny black dots below the aerogel surface. They are incredibly subtle, but many of you are finding them.
We think they are probably inclusions in the aerogel (from the manufacturing process), partly because they are so numerous, and partly because they look like particles, and not like tracks made by particles. They are less likely candidates to be interstellar, but intriguing nontheless. We have logged the coordinates for a number of these black dots and we will continue trying to verify their origin."


From your "My Events" page you should be able to find something like this: Movie 9822413V1 230 45 Not Extraterrestrial inclusion

The Stardust at home scientists have stated that they are not sure what these inclusions are, but will keep trying to find out what they are. We have not been told yet not to click on them.


This topic will be moved and added to the one that already exists Should we still flag likely inclusions?

Thanks,

fjgiie

Alessandro Freda
Posts: 20
Joined: Fri Aug 04, 2006 12:12 pm
Location: Genoa, Italy
Contact:

Re: questions about the inclusions

Post by Alessandro Freda »

DiamondGirl wrote: I'm glad you asked this. I remember seeing someone quote an early post from the home team saying that if you saw anything, no matter how small, to click it. Later some of these inclusion slides ended up causing me to get scored incorrectly, so I modified my strategy and started marking them "bad focus" slides.
--DiamondGirl
You mean that you found some "no track calibration movie" that hold inclusion tracks ?
I think that there is a topic on this forum to submit the ID of these movies.
Also I have found a movie with this problem: 1229264V1
that hold a likely inclusion track. I should submit it but I'm a bit lazy :roll:
so when I've found it the second time, I logout/login to avoid to verify if it was rectify :wink:

Regards
Alessandro

Alessandro Freda
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Joined: Fri Aug 04, 2006 12:12 pm
Location: Genoa, Italy
Contact:

Re: inclusions

Post by Alessandro Freda »

I know. I should read more this forum, but I'm a bit slow to read/translate english language ... so thank you very much for your kind reply.

About my second question, I see now that I not exactly write that I want, so I'll try to resume it on an another topic.

Regards
Alessandro

jsmaje
Posts: 616
Joined: Tue Aug 15, 2006 8:39 am
Location: Manchester UK

inclusions

Post by jsmaje »

OK, I'm posting here the response I got from Dr. Peter Tsou (a principal scientist at JPL) who invented and developed the aerogel sample-collection technique used in various missions including StarDust (see him here: http://stardust.jpl.nasa.gov/news/bio_ptsou.html).

I had asked what they knew about all these so-called 'inclusions' that form the great majority of peoples 'hits'. Though currently judged as non-extraterrestrial manufacturing defects by Dr. Butterworth et al., there has been no unambiguous directive from the Berkeley team as to whether we should continue clicking them, as far as I am aware.

This was Dr. Tsou's (not especially surprising) reply:
Hi John,

Thank you for you and many others' interest on STARDUST. The other
side of the Interstellar Sample Tray containing the samples captured
at comet Wild 2. We have been just thrilled by the unexpected and
exciting large cometary particles; we have now even greater
expectations that the interstellar samples will surprised us even
more, since no one on Earth has seen a free interstellar dust
although many stardusts have been ascertained to have accreted in
some of the extraterrestrial material that we have recovered on Earth.

The fabrication of the silica aerogel used for STARDUST made use the
sol-jel process where SiO2 is bounded with alcohol [Tsou et al. 2004
JGR]. The precursor is a sol, evenly distributed solution of
SiO2. This sol is changed into a jel so individual SiO2 are
connected into a single molecule. This jellation process usually is
not complete, resulting many centers of SiO2 groups. The inert fluid
of the gel now has to be extracted by a critical point extraction
process. This process cause breakdown of the SiO2 network resulting
in more small local clusters. Thus, these clusters are silica
outside of the aerogel network. This is our model of the silica
aerogel fabrication process; with more interest and funding improved
understanding will be gained.

Hope this gives you some help.

Peter
I also mailed Dr. Debel who's done x-ray micro-tomography on the same aerogel (http://research.amnh.org/~debel/tomo-aps/aerogel1.html), and had noted impurities made of "silicon/metal?", though further work was necessary to be sure. No response so far.

Though some of the tiniest calibration tracks can look similar (ignoring the give-away calibration movie clues), I do think that inclusions can be fairly reliably identified as such for well-discussed reasons. I just feel that it's time we had an authorative ruling on whether they want us to continue clicking them or not (some people have independently decided to ignore them, of course).

So, I've forwarded Dr. Tsou's email to Bryan Mendez, who promises to discuss it with Dr. Westphal, with a view to making some sort of official comment before long.

I hope this will help, but if you disagree, feel free!

John

Groundling
Posts: 65
Joined: Sat Aug 05, 2006 6:55 pm
Location: Oregon, USA

inclusions

Post by Groundling »

Just today, I found a CM with "multiple targets". That is to say as I moved down from the "surface", I found an object that seemed to be a "track" but it lost focus in only 2 or 3 bars. As I moved down in focus, that object lost focus and another object came into focus. This new object stayed in focus for more than 6 bars at end of focus.
I am going to use this CM as another benchmark in my search.
For what it's worth.
Groundling
I have met the enemy and he is us.
Pogo

the moon
Posts: 177
Joined: Thu Aug 03, 2006 12:34 am

Post by the moon »

Was the first object right next to the lower one? If so then the first object is actually a surface feature from the original movie the track came from. They cut out a little square around the track and then paste it into many other empty movies. If a surface feature happened to be really close to the track it can show up in there. Then the surface from the empty movie doesn't always match up with the surface from the little square with the track, so it can appear that there are other things under the surface next to the track.

jsmaje
Posts: 616
Joined: Tue Aug 15, 2006 8:39 am
Location: Manchester UK

inclusions

Post by jsmaje »

:D Hooray!!!!
At last, some official advice about inclusions in Bryan Mendez's latest Update:
We are working on updates to the tutorial . The biggest update, still in the works, is some new direction on how to deal with inclusions in the aerogel. We are now confident that they should not be confused with real interstellar dust tracks and are asking volunteers to ignore them much as you would other artifacts like scratches, etc.
So - "Should we still flag likely inclusions?"
Answer - NO! (as long as you're sure that's what they are of course :wink: )

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