Protons and neutrons make up the center (nucleus) of the atom, and electrons form shells around the nucleus.
The number of protons in the nucleus of an atom determines the element.
Cosmic rays enter the earth's atmosphere in large numbers every day.
For example, every person is hit by about half a million cosmic rays every hour.
When miners were sinking a ventilation shaft for the new Crinum Coal Mine in Central Queensland in 1993 (see map below) they unearthed a rare find.
After digging through the thin surface sands and clays, followed by basalt, 21 metres (almost 69 feet) down they found pieces of wood entombed in the bottom basalt flow.
magazine has been continuously published since 1978, we are publishing some of the articles from the archives for historical interest, such as this.
Many people have been led to believe that radiometric dating methods have proved the earth to be billions of years old.A professor emeritus at Texas A&M University College Station, Rowe teaches at a branch of the university in Qatar.Traditional carbon dating involves removing and burning small samples of the object.Carbon-14 is radioactive, with a half-life of about 5,700 years.For more information on cosmic rays and half-life, as well as the process of radioactive decay, see How Nuclear Radiation Works.