How old is earth
The age of the Earth is estimated to be around 4.54 billion years old. This estimate is based on a variety of scientific evidence, including radiometric dating of rocks and minerals, analysis of the Earth's magnetic field, and examination of the fossil record. The age of the Earth is an important topic in fields such as geology, astronomy, and biology, as it provides important context for understanding the development and history of life on our planet.
Alright, seem helpful. 
But another question is how old the Moon is?