Trace radioisotope facts for kids

A trace radioisotope is a special kind of isotope that is radioactive. Think of an isotope as a version of an element. These trace radioisotopes are found naturally in very, very tiny amounts, like just a "trace." They usually don't last very long because their "half-life" (the time it takes for half of their atoms to decay) is much shorter than the age of our Earth.

What Are Trace Radioisotopes?

Trace radioisotopes are radioactive elements that exist in nature in very small quantities. They are different from the stable elements we usually think about because their atoms are unstable. This means they slowly change into other elements over time, giving off energy in the process. This energy is a type of radiation.

Where Do We Find Them?

You can find these tiny radioactive particles in the air around us and deep inside the Earth's crust. Even though they are constantly decaying, new ones are always being made by natural processes.

How Are Trace Radioisotopes Made?

Trace radioisotopes are not just left over from when the Earth formed. They are continuously created by several natural processes happening all the time.

Cosmic Ray Fission

One main way they are made is through something called cosmic ray fission. Imagine tiny, super-fast particles from space, called cosmic rays, crashing into atoms in our atmosphere. When these high-energy cosmic rays hit an atom, they can cause it to split into smaller, lighter pieces. Some of these pieces are new trace radioisotopes.

Neutron Capture

Another way trace radioisotopes are formed is through "neutron capture." This happens in places where there are uranium ores, which are rocks containing uranium. Sometimes, a tiny particle called a neutron gets absorbed by a uranium atom. This can turn the uranium into new, radioactive isotopes like uranium-236 or plutonium-239.

Spontaneous Fission and Alpha Decay

Heavy elements like thorium and uranium are naturally unstable. They can break apart on their own in a process called "spontaneous fission." They can also undergo "alpha decay," where they release a small particle called an alpha particle. When these heavy elements decay, they often create other radioactive elements as intermediate steps in their decay chain. These intermediate elements are also trace radioisotopes.