Mind-Blowing Study Suggests Earth Is Actually Two Planets Fused Together
The Earth may be made of two planets that fused together at the same time the moon was formed.
Scientists long believed a small planet called Theia crashed into the Earth around 4.5 billion years ago, resulting in a large piece of debris that became the moon.
Up until recently, however, this crash was thought of as a sideswipe that allowed Theia to continue its path through space.
In 2012, a new theory emerged that hypothesized there was a head-on collision in which Earth absorbed Theia.
According to ScienceAlert, astronomers at the University of California, Los Angeles led by Professor Edward Young recently uncovered evidence supporting the 2012 theory.
The team compared the chemical makeup of rocks taken from the moon and volcanic rocks from Arizona and Hawaii, Huffington Post reports.
The researchers determined the moon and the Earth have the same oxygen isotope ratios, which are used to distinguish the chemical signatures of each planet in the solar system.
In a statement, Young said,
We don't see any difference between the Earth's and the moon's oxygen isotopes; they're indistinguishable.
According to the researchers, if Theia had just sideswiped Earth, the moon would mostly be made up of Theia and possess an entirely different chemical makeup than Earth.
But the UCLA team found this was not the case.
Theia was thoroughly mixed into both the Earth and the moon, and evenly dispersed between them. This explains why we don't see a different signature of Theia in the Moon versus Earth.
The current shape of the Earth may very well be due to the absorption of Theia.
Some scientists claimed Theia was likely the size of Mars, but the UCLA team believes Theia was about as big as Earth.
This research was originally published in Science magazine.
Citations: Earth is made up of two planets fused together, new research suggests (ScienceAlert), Earth Is Actually TWO Planets, Study Finds (Huffington Post), Moon was produced by a head-on collision between Earth and a forming planet (UCLA Newsroom), Oxygen isotopic evidence for vigorous mixing during the Moon-forming giant impact (Science)