Scanning Electron Microscope?
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Fjgiie, I am back & Thanks, Klemek
Fjgiie, I went to the NASA site and read everything on that news item and I am back.
Klemek, I know that's not what we're here for, and, of course, the scientists can't be going off on tangents, but since this forum is for general science discussion, when Wolter said, in air: air; in space: nothing, it popped into my head that space was not just nothing - it (maybe) contains dark matter (23% according to NASA). Also, thanks for explaining about dark matter not emitting radiation so it can't be measured that way.
Klemek, I know that's not what we're here for, and, of course, the scientists can't be going off on tangents, but since this forum is for general science discussion, when Wolter said, in air: air; in space: nothing, it popped into my head that space was not just nothing - it (maybe) contains dark matter (23% according to NASA). Also, thanks for explaining about dark matter not emitting radiation so it can't be measured that way.
Good Article
Hi marymouse,
And the article was very informative wasn't it ? We hear sometimes about dark matter and I do not know what that is. So anything we can find out about it is great.
Thanks for comming back, and now you may jump all over me when I make a mistake. (once only please)
23 % aye?
Thanks,
fjgiie
And the article was very informative wasn't it ? We hear sometimes about dark matter and I do not know what that is. So anything we can find out about it is great.
Thanks for comming back, and now you may jump all over me when I make a mistake. (once only please)
23 % aye?
Thanks,
fjgiie
Re aerogel:
Re dark matter:
Right. Two questions then arise - just how quickly does the air diffuse out when in space, and back in on return? And if the collector is now full of air again, would the chemical composition of star dust (as perhaps measured by electron beam instruments, mentioned above by arsampson) be altered by oxidation? Would it matterWolter wrote: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
Re dark matter:
I reckon we've seen quite a lot of it already, only the Berkely team insist on calling it 'inclusions'fjgiie wrote:We hear sometimes about dark matter and I do not know what that is
If only it were that simple!jsmaje wrote:I reckon we've seen quite a lot of it already, only the Berkely team insist on calling it 'inclusions'
Icebike had some great links about dark matter here:
http://stardustathome.ssl.berkeley.edu/ ... c&start=15
See page 2. These links also have more links that give more information on it. We should probably continue the dark matter discussion on the Other Space News thread in the Community Forum so that we are posting in approprate places.
Dark matter...I can't help but think of Darth Vader when I hear it!
From dust we come
Just found this about the MIR collector: http://www.lpi.usra.edu/meetings/lpsc97/pdf/1385.PDF, where they say that the platinum retainer wires were found to be stretched, probably because "...entrained air in the aerogel could not escape quickly enough to equalise the internal and rapidly decreasing external pressures during launch, thus causing the aerogel to bulge and the wires to stretch".fjgiie wrote: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?
Apparently it was without other structural problems, at least to visual inspection.
time waste
Everyone is aware that getting samples into an EVACUATED sem takes ages, right?
Ages? How long would that actually be? Excuse me, I'm totally ignorant about this technique. Or (doh!) do you mean it's evacuated after the sample's put in?sub212 wrote:Everyone is aware that getting samples into an EVACUATED sem takes ages, right?
Whatever, it doesn't seem to have stopped them using the SEM: http://www.astrobio.net/news/article1879.