This simplistic model of an atom shows protons as red spheres in the central nucleus. This model is NOT to scale; to match the scale of the nucleus the electrons (yellow) should be much smaller and much further away from the nucleus.
Original artwork by Windows to the Universe staff (Randy Russell).

A proton is a type of tiny particle. All atoms have protons in them, along with electrons. Most atoms also have neutrons.

Protons and neutrons are just about the same size. However, protons are much, much bigger than electrons. A proton is more than 1,000 times as heavy as an electron!

Protons and electrons have an electrical charge. Protons have a charge of +1, while electrons have a charge of -1.

Protons and neutrons are found in the nucleus of an atom. Usually there are about as many protons as neutrons. For example, the nucleus of a normal oxygen atom has 8 protons and 8 neutrons.

Sometimes protons are found outside of atoms. Some of those protons can get moving very, very fast. Protons like that are a type of particle radiation.

Atomic Physics and Particle Physics

Fundamental Physics relevant to Space Weather

Space Weather

A Matter of Scale - interactive showing the sizes of things, from very tiny to huge - from NSF

Last modified September 17, 2010 by Randy Russell.

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