Astronomy The moon is at least 80 million years older than previously thought
According to analyses, the moon is between 80 and 180 million years older than previously assumed. According to a new study, the previous age estimates did not take an important phenomenon into account.
18.12.2024, 17:00
SDA
As reported by a trio of researchers from the USA, France and Germany, the tidal effect of the Earth heated up the Earth's satellite once again 4.35 billion years ago. As a result, large quantities of magma from the interior have rushed to the surface. The age of most of the rock samples from the moon's surface reflects the cooling of this magma and not the formation of the moon, according to the scientists in the journal "Nature".
Shortly after the formation of the primordial Earth around 4.5 billion years ago, there was another huge collision in the solar system: the Mars-sized celestial body Theia collided with the primordial Earth. The collision catapulted large quantities of red-hot rock from the crust and mantle of the two celestial bodies into space - the moon was formed from these remnants of the planetary catastrophe.
But when exactly did this happen?
Rock samples brought to Earth by the "Apollo" astronauts and a series of unmanned missions provided an age of 4.35 billion years for the cooling of the lunar surface. This was therefore previously considered to be the age of the Earth's satellite. However, the researchers also found crystalline inclusions in the lunar rock, so-called zircons, which were older. This raised doubts about the assumed age of the moon.
Francis Nimmo from the University of California, Thorsten Kleine from the Max Planck Institute for Solar System Research and Alessandro Morbidelli from Sorbonne University have now presented a solution to the dilemma. The newly formed moon initially followed a highly elliptical orbit very close to the Earth. In the process, the Earth satellite went through a phase of very strong tidal forces that heated up its interior, transported magma to the surface and thus caused an apparent rejuvenation.
The considerations of the three researchers now provide an age of 4.43 to 4.53 billion years for the moon. This, the scientists emphasize, also fits much better with the dynamic models of planet formation in the solar system.
