Which naturally occurring radioactive particles are the largest?

Alpha particles are the largest type of naturally occurring radioactive particles. They consist of two protons and two neutrons, which means they have a relatively high mass compared to other forms of radiation. This composition gives alpha particles a strong positive charge.

In contrast, beta particles are smaller, as they are essentially high-energy electrons or positrons, whereas gamma rays are not particles but rather electromagnetic radiation with no mass. Neutrons are subatomic particles found in the nucleus of atoms, and while they are similar in size to alpha particles, they are not typically classified as radioactive particles released during decay processes like alpha and beta emissions are. Thus, when considering the characteristics of these particles, alpha particles clearly stand out as the largest in size.