Primary protons are a part of the nucleus of cosmic rays. Cosmic rays are highly charged particles originating from outer space. Berkeley Study Lab suggests that a number of sources could have helped to create this energy, including black holes, neutron stars, supernovae, active galactic nuclei, quasars and the Big Bang itself. Primary protons are particles in which the nucleus makes up more than 95 percent of the particle.
Some protons get booted back into space because they don't have enough energy to break through Earth's magnetic field. Those that do are called primary protons. Primary protons are loose protons that travel through the galaxy by the push of solar winds. The sun's solar winds have an impact far beyond Pluto. Primary protons are positively charged particles with immense energy. They are also a portal to look back in time as it could take them millions of years to actually reach Earth.
All primary protons experience a nuclear collision, causing violent explosions before they ever make it to Earth's surface. They collide with nuclei of nitrogen and oxygen, breaking up into smaller particles. Some protons and neutrons on both sides evaporate in the process. Some of the particles break down into electrons. In the book, In "Analysis of Environmental Radionuclides," P. Povinec explains that entering the atmosphere takes half of the massive energy that propels and is bottled up in primary protons. The collisions could wipe it from existence.
Secondary particles are created out of the nuclear explosions that happen between primary protons and nitrogen and oxygen particles in the earth's atmosphere. In "Astronomy Methods" Hale Bradt writes that secondary particles only exists for microseconds or less because that's how long the nuclear collisions happen. Afterward, they become even smaller particles if they do not evaporate.