Once the principle behind this method was discovered, however, it became possible to gather reliable information about the age of Earth and its rocks and fossils.
Radioactive dating was not possible until 1896, when the radioactive properties of uranium (a radioactive metallic element) were discovered by French physicist (a person specializing in the study of energy and matter), Antoine Henri Becquerel (1852–1908).
Ever wonder how scientists concluded the age of the earth to be about 4.6 billion years old or how geologists determined the ages of caverns, rocks, volcanoes and the Himalayas? Well, scientists are able to answer all of these wondrous questions and more by use of a process called radiometric or radioactive dating.
Radioactive dating enables geologists to record the history of the earth and its events, such as the dinosaur era, within what they call the geologic time scale.
Within the nucleus, we find neutrons and protons; but for now, let's just focus on the neutrons.
These neutrons can become unstable, and when they do, they release energy and undergo decay. Radioactivity occurs when the nucleus contains an excess amount of neutrons.
When an atom varies in the number of neutrons, the variation is called an isotope. During radioactivity, the unstable isotope breaks down and changes into a different substance.
Different isotopes have different half-lives and sometimes more than one present isotope can be used to get an even more specific age of a fossil.During this decay, one substance actually changes into another and radiation is released.As long ago as 1907, the American chemist Bertram B.is a technique used by scientists to learn the ages of biological specimens – for example, wooden archaeological artifacts or ancient human remains – from the distant past.It can be used on objects as old as about 62,000 years.