A new study published on Wednesday suggests that the moon is between 80 million and 180 million years older than previously thought.
The study, published in the journal Nature, says that rock samples from the moon's surface have been incorrectly dated.
The three researchers from the United States, France and Germany argue that 4.35 billion years ago, the moon was traveling close to the Earth on a highly elliptical orbit.
During this time, Earth's strong tidal forces rapidly heated the moon, causing it to release large amounts of magma from its interior to the surface, they say.
Most rock samples from the moon's surface reflect the cooling of this magma and not the actual formation of the moon, the researchers argue.
Instead, they explain that shortly after the formation of Earth around 4.5 billion years ago, it collided with a celestial body the size of Mars, named Theia.
The impact catapulted large quantities of glowing rock from the crust and mantle of the two bodies into space, with some remnants forming the moon, they say.
Rock samples brought to Earth by astronauts on the early Apollo moon missions and a series of unmanned missions indicated that the moon's surface cooled down 4.35 billion years ago, which was assumed to be its age.
But researchers also found crystals from a mineral called zircon in the moon rock, which were even older, raising doubts about the assumed age of the moon.
In their study, Francis Nimmo, Thorsten Kleine and Alessandro Morbidelli suggest the moon is between 4.43 and 4.53 billion years old.
They note that this explanation fits better with the dynamic models of planet formation in the solar system.
