Radioactive elements used in absolute dating
We have rocks from the Moon (brought back), meteorites, and rocks that we know came from Mars.
This time is known as the half-life of the radioactive isotope.On the other hand, the number of neutrons that can be contained in the nucleus can vary.When the number of neutrons is in balance with the number of protons (which does not necessarily means that the number of neutrons has to be exactly the same as the number of protons) then the atoms of a particular element is said to be stable.Earth) and what could happen to Earth in an extreme case, etc.From Wikipedia, radioactive decay is the process in which an unstable atomic nucleus spontaneously loses energy by emitting ionizing particles and radiation.When the number of neutrons is not in balance with the protons then the atom of that particular element is said to be unstable.
In nature, all elements have atoms with varying numbers of neutrons in their nucleus.
We have an activity in one of the PSI workshops "Exploring the Terrestrial Planets," that deals with this topic.
So, you can use the radioactive elements to measure the age of rocks and minerals. Their useful range is from about 1/10 their half-life (the time it takes for half of the radioactive element/isotope-- the parent, to convert into a non-radioactive element/isotope-- the daughter) to 10 times their half-life. You can use this to measure the age of a rock from about 128 million years to more than 10 billion years (the Solar System is 4.56 billion years old).
This decay, or loss of energy, results in an atom (element) of one type, called the parent nuclide transforming to an atom of a different type (another element or another isotope of the same element), named the daughter nuclide.
For example: a carbon-14 atom (the "parent") emits radiation and transforms to a nitrogen-14 atom (the "daughter").
Based on our study of meteorites and rocks from the Moon, as well as modeling the formation of planets, it is believed (pretty much well-established) that all of the objects in the Solar System formed very quickly about 4.56 billion years ago.