What makes radioisotopes useful for dating objects
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.
The biggest assumption is that, to first order, the number of asteroids and comets hitting the Earth and the Moon was the same as for Mercury, Venus, and Mars. The bottom line is that the more craters one sees, the older the surface is.
This can be interpreted in two ways: why it is important to know the age of a planet or how is age dating important in determining the age of a planet?
These are the surfaces that we can get absolute ages for.
For the others, one can only use relative age dating (such as counting craters) in order to estimate the age of the surface and the history of the surface.
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.
The effects of impacts and how they might affect us here on Earth, global climate change (Venus vs.
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.
We have rocks from the Moon (brought back), meteorites, and rocks that we know came from Mars.
We can then use radioactive age dating in order to date the ages of the surfaces (when the rocks first formed, i.e. We also have meteorites from asteroids and can date them, too.
We can get absolute ages only if we have rocks from that surface.
For others, all we are doing is getting a relative age, using things like the formation of craters and other features on a surface.