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 Incoming gamma radiation 
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@Bert490 - Thank you for the recent update.

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MY OUTSIDE RADIATION MONITORING STATION:
South Beloit, Illinois - GMC200 Outside on HEPA air purifier, ground level, facing West.
http://netc.com/chart/view.php?n=1%3AEB5A139C


Wed Sep 07, 2016 5:42 am
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Location: Arkansas
I tried a lead apron from my dentist, he had an old one. It did not help me either. That was last year. I think the lead should be at least 6 to 12 inches. But what do I know, with only a gmc-320 to use.


Thu Sep 08, 2016 8:19 pm
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Joined: Sat Feb 01, 2014 3:46 pm
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I'm beginning to realize that you need a gamma-only tube with a very low inherent background count, less than 2 cpm. The LND714 is a 1 inch long tube with a bkg of 1 or 2 cpm. Then you need to be in a location where you have a clear view of the sky,with your setup well above the ground level. Hopefully the radon background is also very low in your area. The more sensitive pancake tubes pick up way too much alpha and beta from background sources. Even with lead shielding, the open air above the gamma tube still contributes a considerable portion of the background activity. The orbiting sources are quite weak and may actually be absorbed by 1/4 inch of lead or less. Using paper or even thin lead film to shield alpha and beta on larger tubes doesn't seem to help much.
This project is turning into a major production, with over 3000 satellite debris in the catalog and 4 networked computers running 24/7 calculating orbits and correlating radiation readings with satellite debris passing overhead.
So far after over two months of steady data capture and what little analysis can be done, I am just beginning to identify candidates that might be the culprits. There are four dead satellites that each have separate debris fields streaming behind them. The main satellite does not seem to have as much activity in each case, but something in the debris is active and might be an un-cataloged item, or possibly in the catalog but classified and not published.


Tue Sep 27, 2016 6:27 am
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At the end of this month I will post the consistent suspects by its' NORAD catalog number so some of you can take a crack at detecting something. With several folks looking for the same items, it might be possible to pool the results and make a definitive statement regarding what the source is, and when it might decay and hit the ground.


Tue Sep 27, 2016 7:07 am
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Joined: Fri Jul 03, 2015 7:04 pm
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Location: Toronto Canada
I agree that it will take a coordinated effort, as I have only seen hints in my few observations so far. I wrapped all the lead at my disposal around the bottom of the detector, resulting in the 3/4" / 18mm thick box shown. This reduces overall counts by only 20%, so it's only partially effective at isolating sky sources.
Image
With this setup I am recording time-stamped readings in uSv/hr, and graphing the results. A representative graph is shown below. The horizontal axis is time, and the red lines are the Start and End times of the Snapshot satellite's appearance over my location (on Sept 21). First off, it is clear that there is no strong rise, so these satellites do not seem to be a danger to the public right now (as long as they stay up there!). Also, there is no clear peak in the middle, the closest point. The rise at the right side of the window, where the satellite is almost gone from view, might be a trailing piece of debris as Peter is suggesting, but it might also be random.
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More and better setups are needed. Thanks, Peter for doing all this correlation; we look forward to continuing the investigation.

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http://netc.com/chart/view.php?n=1%3A77D9CCCA.5 Toronto, Ontario, Canada SBM-20 indoors


Tue Sep 27, 2016 11:04 pm
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I can see the rise and sudden drop at the edge which is exactly what you should see, and, yes the main body is probably not as active as one might expect, possibly not active at all. Another point to consider is that many orbiting pieces of space junk can be seen to rotate as evidenced by the periodic flashes of reflected sunlight during some observations. If one can envision a shielded source with a blown out hole in one side rotating in orbit, you will then expect there to be periodicity in the gamma traces as well. Most all of my data also seems to agree with Bert's observation...indeed it may be right behind the main satellite body, possibly an ejected reactor.


Sat Oct 01, 2016 2:17 pm
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Joined: Sun Jan 04, 2015 12:01 am
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I can share a bit of data concerning insulating background rads. 1 I spoke to a person at a manufacturing business that made radiation insulating glass, very pricey . Then he told me that one inch thick glass should keep out all background radiation. Easy enough to get thinner glass and laminate it to one inch. This should work good for a food testing container, or possibly your application , also. 2 Calcium carbonate, which is mined in large rock quarry's will probably be found to help against radiation . I like your progress, thanks.


Wed Oct 12, 2016 10:07 pm
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Great find, Islander! Calcium carbonate is available as garden lime.


Sun Oct 16, 2016 6:51 am
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Location: Toronto Canada
After some months of testing, I can conclude that the broken-up nuclear satellite Snap-10A is not detectable on the surface, at least with my setup (photo below). The radiation rise I saw on Sept 21, 2016 was not seen again so it cannot be associated with this satellite. I put more layers of lead on the bottom and sides of my detector, and graphed more satellite passes as predicted by n2y0.
Image
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I have 16 passes graphed and none after Sept 21 show a noticeable rise or any kind of repeating pattern. The graphs here are the passes almost directly overhead. Now I did not do any numerical analysis, but based on the graphical results, there is no rise in radiation.

So I think this satellite is not dangerous to people in its present orbit. Maybe its shielding is still intact, despite being is 50 pieces; maybe it is emitting radiation but is too far away (only the Space Station or other satellites can get closer). At any rate, it is still dangerous due to the orbital decay prediction of 3,000 years being much smaller than the half-life of its fuel.

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http://netc.com/chart/view.php?n=1%3A77D9CCCA.5 Toronto, Ontario, Canada SBM-20 indoors


Sat Mar 04, 2017 4:24 pm
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Bert490 wrote:
...At any rate, it is still dangerous due to the orbital decay prediction of 3,000 years being much smaller than the half-life of its fuel.


We have created so much nuclear waste in space and here on Earth and the elites are worried about climate change from carbon emissions. Simply amazing.

:arrow: Thanks Bert for your research and follow-up to this post.

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MY OUTSIDE RADIATION MONITORING STATION:
South Beloit, Illinois - GMC200 Outside on HEPA air purifier, ground level, facing West.
http://netc.com/chart/view.php?n=1%3AEB5A139C


Sun Mar 05, 2017 2:29 pm
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