For the last few months I have been running an experiment to see if there is any increase in ground level radiation when known broken, radioactive satellites pass overhead.  Over 30 satellites have nuclear power sources, and the long term impact of the nuclear waste has not been dealt with much.  The expected orbital life (some 3,000 years in one case) is far less than the half-life of the fuel.  One such satellite crash-landed in Canada in 1978, luckily in an un-populated area.  Of those in orbit, some are known to have broken up due to impact with debris.  I chose to study Snap-10A as it is known to be in about 50 pieces now, and the orbital passes are not hard to find (using  It is about 1300 km above the earth.

To make the GM-tube detector (SB20) more sensitive to satellite radiation, I wrapped the detector on 5 sides with 35mm / 1.4" of lead sheeting (11.3 kg / 25 lb).  This thickness is enough to reduce the gamma interference from below and the sides only by about 30%, so it's not ideal but it will make any radiation from above a bit easier to see.  It certainly blocks beta radiation.  The GM tube is at the bottom of this detector, so the 'window' is a rectangular cone with a narrow width of about 25 degrees.  The intent is to use it parallel to the satellite path to get basic correlation from orbit to orbit, then turn it cross-ways to see a more definite rise and fall on subsequent orbits.

This detector sends raw readings every second, which was captured to a log file and time-stamped with Tera Term software.  Data analysis was done using MS Excel to chart the readings from 1 hour before the orbital pass to one hour after.  Each pass overhead for this satellite is about 20 minutes.  The expectation was to see a rise in the radiation readings during those 20 minutes compared to the hour before and after.  Here are the charts:

When I saw this first one, I thought I was onto something, like a trailing bit of debris after the tracked main satellite body passed overhead.  But as you can see, this did not repeat:

Overall, the radiation during the 'visible' times does not rise compared to when this satellite is not overhead.  So I think this satellite is not dangerous to people in its present orbit. Maybe its shielding is still intact, despite being in 50 pieces; maybe it is emitting radiation but is too far away (only the Space Station or other satellites can get closer).

I would like to chart other satellites, but I don't know the passing times of any other broken nuclear satellite.

This detection is unconfirmed, but potentially concerning. Awaiting further news. See discussion on the forum

A hole has been detected in the Earth’s magnetic shield.  Data from the GRAPES-3 muon telescope in Ooty, India shows the magnetosphere has come under such heavy bombardment in recent years that it weakening. Researchers  in India made the discovery when analyzing a galactic cosmic ray burst that caused radio blackouts across North and South America and a supercharged aurora borealis in 2015. The magnetic field that protects Earth from deadly cosmic radiation may be more vulnerable than previously thought.  A crack in the shield caused by a solar flare which exposed the planet to a bombardment of radiation has been detected.

The cosmic ray source was a giant solar plasma cloud that travelled 40 hours from our sun to reach Earth, where the researchers believe it caused a transient “weakening of Earth’s magnetic shield”, according to their findings published in the journal Physical Review Letters.

Unfortunately not a lot can be done to protect Earth from any future cracks in the shield, which could leave the planet under constant exposure to radiation and could potentially lead to the eradication of our atmosphere.

Vladimir Putin’s military may have carried out a secret Arctic nuclear test after a huge spike in dangerous radiation levels were detected across Europe. The worrying claims came as the US Air Force sent a special WC-135 Constant Phoenix – whose main mission is to detect and identify nuclear explosions from the air – to RAF Mildenhall.

See forum thread here:

his is significant as Iodine 131 has a short half life and is only emitted in large quantities in a nuclear accident.

Possible detection of washout by radmon station Simomax?

Or a nuclear test?? (thx Bethsalem)

GK-B5 SI-180G tube in Gothenburg / Sweden
'The reactor at the Institute for Energy Technology in Halden, southern Norway, spilled radioactive iodine isotopes on Monday, according to the Norwegian Radiation Protection Authority (NPRA).

"The radioactive leak was due to a technical failure during treatment of the fuel in the reactor hall. Emissions are low,” the NRPA said.

Staff at the facility were evacuated immediately after the incident but the NPRA was not informed until the following day.'
Worcester, MA. USAGMC-320+V4M4011Counter is set up next to a north facing window, opened occasionally
Welcome to fell in Hronske Kosihy, Slovakia.
fell has a RH electronics DIY counter with SBM-20 tube

Welcome to EricFu in Pottendorf, buy meridia online, Baden, Austria.
EricFu has a GQ GMC-320 with M4011 tube.

Welcome to hexxter in Virgo Supercluster/Milky May/Orionarm/Sun System/Earth/Central Europe/Germany/Bavaria/Kallmünz (haha)
hexxter has a BroHogan GK-RadMon with SBM-20 tube.

Welcome to westerbergwetter in Osnabrück, Germany.
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Great to have you all here at :D
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Hello I do not know English. I want to join in  SBM-20 и Arduino IDE DIY Geiger Kit ver. 1.01 with EEPROM logging  Radiation LoggerI'm in Bulgaria, Sofia
At last the V0.42 alpha is available. I know its been a long time, lots of features were added - too many at once which bogged down development until it was good enough to release. It is an alpha release, so use only if you want to test and report bugs back.

New features

- Lite/Pro mode removed
- Coincident events and reporting
- Multiple serial formats, MightyOhm compatibilty added
- GPS position reporting from GPS USB stick
- SFTP and FTP mode. Different graphs and analysis can be uploaded
- Counter failure emails
- Multiple warning and alert emails
- Station synopsis and coincidence lists in Log and Shared Log
- Adjustable envelope detection for audio mode
- Report to APRS via internet
- Radio beacon modes CW, QRSS, Hellschreiber for 30m etc. If you set up a 30m beacon with this, please let me know I would love to RX it or find it on a QRSS grabber somewhere..
- APRS radio packet mode VHF and HF. This has a bug preventing operation. If you can analyse APRS packets, please check the test packet and help me find the last bug..

Here's the link
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