Earth dating systems
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.
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.
In nature, all elements have atoms with varying numbers of neutrons in their nucleus.It is impossible to predict when a given atom will decay, but given a large number of similar atoms, the decay rate on average is predictable.This predictable decay is called the half-life of the parent atom, the time it takes for one half of all of the parent atoms to transform into the daughter.By studying other planets, we are learning more about our own planet.The effects of impacts and how they might affect us here on Earth, global climate change (Venus vs.