Why there are only 45 interstellar dust particles?
Moderators: Stardust@home Team, DustMods
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Why there are only 45 interstellar dust particles?
Why there are only 45 interstellar dust particles in 1,000 square centimeters?I think the rate is too low?
And also I wanna to know if the aerogel collector is bigger,for example,1 square meter, that we will get more stardusts,am I right?But why
didn't it?
Thank you!
--CunhuaiZheng
And also I wanna to know if the aerogel collector is bigger,for example,1 square meter, that we will get more stardusts,am I right?But why
didn't it?
Thank you!
--CunhuaiZheng
Here's the most simple answer I can think of to answer your question. Dust is very very small. Outer Space is HUGE. There's nothing to stop the dust from spreading out in any direction in space until it hits something else in space. Consequently, it isn't likely to be more plentiful or compact than a certain amount.
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The average density of interstellar dust particles in the part of the Solar System where they were collected is about 1 particle per cubic kilometer. This was independently measured by two previous NASA spacecrafts, Galileo and Ulysses.
The collector area is about 1000 square centimeters and it collected for about 6.5 months moving at a speed relative to the interstellar dust stream of 20 km/s. When you calculate how many particles should have been collected, the number is 45.
Incidentally, I'm making up a math problem for students to do this calculation as part of a lesson guide for Stardust@home.
Yes, if the collector had been bigger, it would have collected more particles.
-Bryan
P.S. This topic belong more in the Discussion forum so I'm moving it there.
The collector area is about 1000 square centimeters and it collected for about 6.5 months moving at a speed relative to the interstellar dust stream of 20 km/s. When you calculate how many particles should have been collected, the number is 45.
Incidentally, I'm making up a math problem for students to do this calculation as part of a lesson guide for Stardust@home.
Yes, if the collector had been bigger, it would have collected more particles.
-Bryan
P.S. This topic belong more in the Discussion forum so I'm moving it there.
"I am made from the dust of the stars, and the oceans flow in my veins"
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Interesting. If 45 is the correct number, then the dust density must be about 1.31 particles/km^3. According to your numbers, the volume swept by the collector was 34.187 km^3.
See volume calculation here: http://www.google.com/search?hl=en&q=10 ... +in+km%5E3
(edited: I guess the url tags don't work.)
See volume calculation here: http://www.google.com/search?hl=en&q=10 ... +in+km%5E3
(edited: I guess the url tags don't work.)
...Tom
visit #space on IRC.freenode.net
visit #space on IRC.freenode.net
Here you go cosmic, tinyurled it for you.
http://tinyurl.com/ztr4f
http://tinyurl.com/ztr4f
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Thanks, geckzilla. I guess the point we should all take home is that very few stardust tracks are to be expected over the entire tile array. Also note that only about 15-20% of the tiles have been made into available movies.
http://stardustathome.ssl.berkeley.edu/ ... c.php?t=78
So only about 10 tracks would be predicted to have been found in all of the work people have done so far. It appears that the spatial particle density in the above equation was not over-estimated. Perhaps no stardust tracks have been found yet. I guess we had better keep dusting.
http://stardustathome.ssl.berkeley.edu/ ... c.php?t=78
So only about 10 tracks would be predicted to have been found in all of the work people have done so far. It appears that the spatial particle density in the above equation was not over-estimated. Perhaps no stardust tracks have been found yet. I guess we had better keep dusting.
...Tom
visit #space on IRC.freenode.net
visit #space on IRC.freenode.net
As you mention, I too wonder if we have found 10 particles or so. Surely we must have found some.
Unless, of course, the % of bad-focus has been unfortunately high. Still, even so, if you said proper coverage on even half of those scanned so far(and that'd be quite conservative perhaps), we'd expect maybe ~5 genuine particles!!...
Let's hope so!!
Unless, of course, the % of bad-focus has been unfortunately high. Still, even so, if you said proper coverage on even half of those scanned so far(and that'd be quite conservative perhaps), we'd expect maybe ~5 genuine particles!!...
Let's hope so!!
Twinkle, twinkle, little dust!
How I wonder which to trust!
From stars above the world you fell!
Buried like treasure in aerogel.
How I wonder which to trust!
From stars above the world you fell!
Buried like treasure in aerogel.
I think you've answered your own question, alexz. [as did cosmicrocker, from the other angle]
With an expectation of only up to 10 genuine tracks in the processing so far... Even less, given the bad-focus movies...
That's on the order of maybe 1 per 1000 people looking for a week!
(1 track per 200 people, at final say, wouldn't be bad though!!!)
PS -- quote:"1 particle per cubic kilometer" -- what a tremendous mental picture that is!
With an expectation of only up to 10 genuine tracks in the processing so far... Even less, given the bad-focus movies...
That's on the order of maybe 1 per 1000 people looking for a week!
(1 track per 200 people, at final say, wouldn't be bad though!!!)
PS -- quote:"1 particle per cubic kilometer" -- what a tremendous mental picture that is!
Twinkle, twinkle, little dust!
How I wonder which to trust!
From stars above the world you fell!
Buried like treasure in aerogel.
How I wonder which to trust!
From stars above the world you fell!
Buried like treasure in aerogel.