Scanning Electron Microscope?

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Should they scan potential tracks with better imaging (Ex. Electron Microscope)?

Yes
7
33%
No
7
33%
Maybe
4
19%
Dont' care
1
5%
What's a Scanning Electron Microscope?
2
10%
 
Total votes: 21

WeBeGood
Posts: 65
Joined: Thu Aug 03, 2006 7:26 am
Location: Texas, USA

Scanning Electron Microscope?

Post by WeBeGood »

Are they going to change the sensor on the automated microscope to some like a Scanning Electron, or better? I'd like to look for entry holes in the aerogel. These in particular are on my list. Just wondering?

Are any of the particles moving fast enough, or that are small enough (probabilistically speaking) that they would not create and entry hole at the surface? Would a clump of a few atoms be able to fly into the aerogel, missing the surface entirely. Hitting the aerogel some distance in and create a small visible defect.
JohnPenny, nexguy and ..., wrote:
Image
Image
Last edited by WeBeGood on Sat Aug 05, 2006 7:28 am, edited 1 time in total.

lrmerte
Posts: 1
Joined: Sat Aug 05, 2006 2:46 am
Location: Seattle, WA, USA

Re: Scanning Electron Microscope?

Post by lrmerte »

That would be silly. For a number of reasons.

Sagastar
Posts: 22
Joined: Thu Aug 03, 2006 6:11 am

Post by Sagastar »

i'd like to see the stardust itself under a sem.

templar781
Posts: 38
Joined: Thu Aug 03, 2006 9:19 am
Location: St. Petersburg Florida
Contact:

Post by templar781 »

The candidate tracks that we submit will be analyzed further by reviewing the high res photo of that track. If they determine that the candidate is still a "good" track then they will analyze the cell by hand. What they use at that point they're not saying but I would think that they wouldn't use a SEM until after they've found and retrieved an actual interstellar particle. There are several other types of microscopes that offer even better resolution than SEMs and you can read a little about them here http://www.che.utoledo.edu/nadarajah/we ... tsafm.html
Winning isn't everything, but wanting to win is. - Vince Lombardi

WeBeGood
Posts: 65
Joined: Thu Aug 03, 2006 7:26 am
Location: Texas, USA

Post by WeBeGood »

I would think there are better microscopes for looking into the aerogel too. SEMs look at the surface like the Scanning Tunneling Microscope (STM) and Atomic Force Microscope (AFM). I would think there is as much to learn looking at the aerogel as there is at looking at the particles. The aerogel contains a record of what went on during the impact. Since aerogel is mostly vacuum, it would also give statistics on very small particle as they might be able to penetrate a little bit before hitting the aerogel. Thanks for the link.
templar781 wrote:The candidate tracks that we submit will be analyzed further by reviewing the high res photo of that track. If they determine that the candidate is still a "good" track then they will analyze the cell by hand. What they use at that point they're not saying but I would think that they wouldn't use a SEM until after they've found and retrieved an actual interstellar particle. There are several other types of microscopes that offer even better resolution than SEMs and you can read a little about them here http://www.che.utoledo.edu/nadarajah/we ... tsafm.html
Courtesy E-Mail Welcome @ WeBeGood@GMail.Com

arsampson
Posts: 3
Joined: Fri Aug 04, 2006 9:08 pm
Location: Chicago

Post by arsampson »

SEM analysis won't be attemped until individual particles are removed from the aerogel. There will probably be some small samples of the aerogel subjected to SEM just to characterize the surface condition and possibly track damage (I wouldn't want to do that cross sectioning), but the SEM doesn't have the ability to penetrate the surface the way an optical microscope can and can't be used to locate these tracks as easily as the optical microscope.

In regards to previous posting, scanning probe microscopes such as an AFM offer little to the analysis of these particles. Electron beam instruments can provide morphological, elemental and crytallographic analysis as well as other techniques that can provide far more information about the particles that can be found and retrieved in these samples than any other single instrument.

I'm not associated with this project except as a volunteer.

icebike

Re: Scanning Electron Microscope?

Post by icebike »

WeBeGood wrote:Are they going to change the sensor on the automated microscope to some like a Scanning Electron, or better?


Dude: Leave it to the PROs, ok?

Sheesh!

I appreciate your enthusiasm, but at least get out of high school before you start taking polls on how the scientists should do their jobs.

Klemek
Posts: 54
Joined: Tue Aug 22, 2006 8:15 am
Location: Seville, Spain

Re: Scanning Electron Microscope?

Post by Klemek »

Hi, I'm a chemistry student, and I have some experience working with SEMs. I'm not sure, if it is possible to improve the quality of aerogel pictures using SEM. The reason is that aerogel doesn't conduct electricity(?). Pictures of non-conductive materials taken by SEM are in most cases blurry, and look like a planet surface covered with heavy storm clouds. That's, what my experience taught me, but I didn't look at aerogel samples using SEM, so I may be wrong. Is there someone, who can confirm or negate my theory? I'm very curious about that.

Wolter
DustMod
Posts: 457
Joined: Mon May 22, 2006 2:23 am
Location: Enkhuizen, the Netherlands

Post by Wolter »

I think you lot tend to forget the reason why we are here.

At this stage of the process the only goal is to find the particals.

It 's the project members best edugated guess that looking for entry marks (tracks) with a optical microscope is the fasted way to do so.

So thats what we do and nothing more.

Further analisys on any found particals will only be done after an entire scientific commity has studied the proposals in order to make sure that the best possible results will get collected.

Happy hunting all.
Just dusting... Image

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

Post by jsmaje »

Only just come across this from Aug 5:
WeBeGood wrote:Since aerogel is mostly vacuum...
Eh? Surely mostly air - that's why it's called aerogel, not vacugel :!:

fjgiie
DustMod
Posts: 1253
Joined: Sat May 20, 2006 8:47 am
Location: Hampton, SC, US

Post by fjgiie »

Hi jsmaje,

I'm glad you brought this up. :) When the Aerogel goes into the vacuum of space, I wonder if the air inside expanding contributes to the brittleness of that material. I wonder if the expanding air ruptures the foam, or just gradually leaks out without damage?

Wolter
DustMod
Posts: 457
Joined: Mon May 22, 2006 2:23 am
Location: Enkhuizen, the Netherlands

Post by Wolter »

from Nasa

"To collect particles without damaging them, Stardust uses an extraordinary substance called aerogel. This is a silicon-based solid with a porous, sponge-like structure in which 99.8 percent of the volume is empty space."

It's porous so nothing wil expand or blow-up in vacuum.
Its volume is 99.8 percent empty, so in air: perhaps filled with air, in space: just nothing there
Just dusting... Image

marymouse
Posts: 64
Joined: Wed Aug 23, 2006 9:52 am
Location: USA

Aerogel - Nothing in it, in space

Post by marymouse »

I know nothing about this, so please don't laugh, but I have heard about dark matter. Would there be dark matter in it? Would we know?

fjgiie
DustMod
Posts: 1253
Joined: Sat May 20, 2006 8:47 am
Location: Hampton, SC, US

Dark Energy

Post by fjgiie »

.
marymouse

go home

Read this all of it

come back

from fjgiie :)

Klemek
Posts: 54
Joined: Tue Aug 22, 2006 8:15 am
Location: Seville, Spain

Re: Aerogel - Nothing in it, in space

Post by Klemek »

marymouse wrote:I know nothing about this, so please don't laugh, but I have heard about dark matter. Would there be dark matter in it? Would we know?
It's not, what we're looking for. Existence of dark matter has not been proved experimentally yet. Dark matter according to some theories is a matter that fills deep space. It doesn't emit any radiation, so it is difficult to observe. It's existence was proposed in order to explain some phenomenons.

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