subatomic particle, also called elementary particle, any of various self-contained units of matter or energy that are the fundamental constituents of all matter. ... As particles collide at high energy, the collision energy becomes available for the creation of subatomic particles such as mesons and hyperons.

Where do subatomic particles come from?

We're awash in neutrinos. They're among the lightest of the two dozen or so known subatomic particles and they come from all directions: from the Big Bang that began the universe, from exploding stars and, most of all, from the sun.

When were subatomic particles created?

The first subatomic particle to be discovered was the electron, identified in 1897 by J. J. Thomson. After the nucleus of the atom was discovered in 1911 by Ernest Rutherford, the nucleus of ordinary hydrogen was recognized to be a single proton. In 1932 the neutron was discovered.