The Moon could have been formed after a huge collision between Earth and an object that was very similar in composition to our planet.

This new theory could help elucidate why Earth and Moon have so much in common in rock composition, more than experts would expect from a giant impact. But this is only one study regarding the origin of the Moon that were published recently in the prestigious journal Nature.

Two other research papers speak about recently unknown differences in lunar rocks. Researchers believe they are crucial in drawing the picture of the Moon’s history.

Scientists from Israel and France have managed to simulate the turmoil of the early Solar System. The study quantifies the number and versions of collisions that might have happened during that time.

In its beginnings, the Earth would have been the scene of an entire string of heavy collisions with other planets in the forming stage. According to the experts, the last of these was a cataclysmic impact with a planetary rock just ten times lighter than Earth. The theory suggests that the resulting debris eventually merged and the Moon was thus formed.

Previous studies believed that the planet that hit Earth was a different type of space object, but new data denies these theories.

“They are almost identical. This is one of the major challenges for this really beautiful giant impact hypothesis,” said Dr Perets, from the Technion-Israel Institute of Technology.

Dr Perets and his colleagues discovered in their simulations that the planet that hit earth might, in fact, have been made of almost identical materials to those already present on Earth, that is why only subtle differences are observed in lunar material.

The new studies have found an interesting explanation for what happened subsequently to both the Earth and the Moon. Researchers have proposed that both the Earth and Moon gathered a huge amount of extra matter, during a subsequent period when the two were bombarded by large numbers of meteorites.

Even if the Moon and Earth had originally similar building blocks, our planet had a much stronger gravity and deprived the satellite from a balance of ingredients during that period.

The two other new studies of lunar rocks, one from Germany and the other from the US, discovered evidence for this shift, after looking at samples from the Apollo missions with new high tech equipment.

They found that a small but important difference when compared lunar rocks to Earth rocks: an altered ratio in the metal’s different isotopes.

Image Source: Feel Grafix