dating sex personal - Radiometric dating age of the earth
Samples returned from the Apollo and Luna missions revealed ages between 4.4 billion and 4.5 billion years, helping to constrain the age of Earth.
How the moon formed is a matter of debate; while the dominant theory suggests a Mars-size object crashed into Earth and the fragments eventually coalesced into the moon, other theories suggest that the moon formed before Earth. ]In addition to the large bodies of the solar system, scientists have studied smaller rocky visitors that have fallen to Earth. Some are cast off from other planets after violent collisions, while others are leftover chunks from the early solar system that never grew large enough to form a cohesive body.
In the early 20th century, scientists refined the process of radiometric dating.
Earlier research had shown that isotopes of some radioactive elements decay into other elements at a predictable rate.
These tiny zirconium silicate crystals have ages that reach 4.3 billion years, making them the oldest materials found on Earth so far. The rocks and zircons set a lower limit on the age of Earth of 4.3 billion years, because the planet itself must be older than anything that lies on its surface.