Plutonium-242

This is Plutonium-242. Pu-242 is a radioactive isotope of Plutonium and has a half-life of 376,000 years, it is a byproduct of nuclear reactor operations and nuclear bomb explosions. Over 376,000 years this will change colour roughly 45 times per year until all the 16,777,216 colours within the RGB colour spectrum are cycled through. Over 376,000 years it will also change frequency at an average rate of around 5-6 times per century, cycling through all frequencies within the human range of hearing.

This cycle will never complete, as the maximum time for this operation is 23:59 on the 31st of December 9999, when the process will expire.