The moon turns out to be 40 million years older than thought

The long-awaited answer to the question about the age of the Moon has become an eye-opening study by American scientists. The scientific community was pleasantly surprised to learn that the Earth's satellite is as much as 4.46 billion years old, which is 40 million years older than previously thought.

The hypothesis of the formation of the Moon after the collision of the Earth with the planet Theia has long been one of the most popular. According to this concept, our satellite was formed from the debris after the impact. However, the exact time of the collision remained a mystery. In light of the doubts and narrow-mindedness of this hypothesis, in 2007 a new approach to explaining the origin of the Moon emerged - the multi-impact approach.

Using new research methods based on the previous concept of the Moon's formation, scientists turned their attention to zircon crystals found in the lunar soil brought back by the astronauts of the Apollo 17 mission in 1972. Scientists were able to date these crystals and found that they are the oldest and were formed after Earth's collision with Theia.

In detail, the study indicates that when the Mars-sized planet collided with our Earth, the energy of the impact must have melted the rock and later, as it cooled, the described zircon crystals were formed.

Lead isotopic analysis by the authors of the new paper confirmed that the age of the sample examined by scientists is 4.46 billion years. Consequently, the same number of years lasts our lunar satellite.

We should not forget about another hypothesis of the formation of the moon - the multi-impact hypothesis, which states that the surface of the satellite never melted. According to this theory, a series of less powerful asteroidal impacts with Earth did not have enough energy to melt the terrestrial materials ejected into space. Recent studies of the water content of lunar basalts that have been lifted from the interior of the Moon fit this hypothesis well, since if these basalts had once melted, they would no longer contain water.

Thus, according to the new interpretation, the age of the Moon could be determined using zircon crystals that may have arrived on the surface of the satellite along with materials ejected from Earth. Thus, these crystals are more likely to tell the age of the Earth's crust than the lunar surface.