Named after a villain in Greek mythology, tantalum is an uncommon heavy metal found in Earth’s crust. By weight, 1.5 parts per million of Earth’s crust is tantalum. Most tantalum is in the form tantalum-181. But 0.01% is in the isomer form of tantalum-180m.
An isomer is a molecule with the same molecular formula as another, but with a different chemical structure. Tantalum-180m is an isomer with a naturally agitated nucleus.
Normally, excited nuclei quickly calm down, dropping to a lower energy state and emitting a photon in the process. Somehow tantalum-180m is stuck in its frenzied state.
After extensive observation, physicists decided that tantalum-180m could not have a half-life shorter than 45 million billion years. No other known element has anywhere near such a determined buzz.
(Half-life is the duration required for a material to decay to half of its initial mass. The term is commonly used in nuclear physics to state the radioactive decay rate of atoms. Because of the uncertainty principle, it is impossible to predict when radioactive decay may occur. So, decay rate is expressed in terms of probability, represented as a half-life.)
The oddest thing is that tantalum-180m even exists. The element-forging processes that transpire in stars and supernovas seem to bypass this nuclide of 73 protons.
We don’t understand how it is created. ~ American nuclear physicist Eric Norman