The conclusion runs counter to the alternate theory that the gas lights up as it cools to release gravitational energy--with no black holes in the picture.

Geiger counter was included to measure radiation if at some point an atom decayed. Should that happen, the Geiger counter would trigger the release of cyanide gas, which would kill the cat.

A Geiger counter was included to measure radiation if at some point an atom decayed. Should that happen, the Geiger counter would trigger the release of cyanide gas, which would kill the cat.