Uploaded March 2014 | Updated September 2026, 2 hours ago

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A simple radiation detector allowing you to see the ionisation trails left by radiation.

Thoriated welding rod contains small amount of the radioactive element Thorium - an alpha emitter.

The alpha source is Plutonium. The short range of the alpha particles can clearly be seen.

The beta source is Strontium. The beta particle create much finer trails and speckles - a result of their lower ionising power.