4.5 Billion Years Ago, Head-On Collision Between Earth And Other Planet Produced Our Moon

Posted: Feb 2 2016, 8:12am CST | by , in News | Latest Science News


Head-on collision between Earth and Theia
Photo credit: William K. Hartmann

Researchers from UCLA have published a study in the journal Science which suggests that our Moon was formed when the Earth crashed into another planet known as Theia about 4.5 billion years ago – nearly 100 million years after the Earth was formed.

Scientists think the head-on collision must have occurred at an angle of 45 degrees; and researchers examined seven space rocks taken from the moon by the Apollo 12, 15, and 17 missions before they could agree on this point.

The scientists were able to assess how the collision between the Earth and Theia occurred by analyzing the chemical signature evident within the oxygen atoms in the space rocks. It is already common knowledge that 90% of rock’s volume is made up of oxygen, which also makes up 50% of their weight.

The only issue however is that most of the oxygen on Earth is made up of eight protons and eight neutrons within each atom, necessitating the need to call this composition O-16; but there is O-17 composition of heavier oxygen isotopes where the proton-neuron combination has an extra neutron; and O-18 with two extra neurons.

The planetary bodies located in our solar system, including the Earth and Mars have O-17 to O-16 ratios, each of them distinctive in its own unique way. “We don’t see any difference between the Earth’s and the moon’s oxygen isotopes; they’re indistinguishable,” said Edward Young, lead author of the new study and a UCLA professor of geochemistry and cosmochemistry.

The research team led by Young used the latest technological advancements to carefully measure the precise quantities of these elements, and then verified the results with UCLA’s new mass spectrometer.

The scientists think the rocks on Earth and on the moon possess the same oxygen chemical signatures because only a head-on collision between the Earth and another planet that did not survive the crash would create the moon and make the chemical signatures in them similar. A sideway crash impact would not have created the chemical signatures.

“Theia was thoroughly mixed into both the Earth and the moon, and evenly dispersed between them,” Young said. “This explains why we don’t see a different signature of Theia in the moon versus the Earth.”

The research was funded by NASA, the Deep Carbon Observatory and a European Research Council advanced grant (ACCRETE).

You May Like


The Author

<a href="/latest_stories/all/all/52" rel="author">Charles I. Omedo</a>
Charles is covering the latest discoveries in science and health as well as new developments in technology. He is the Chief Editor or Intel-News.




Leave a Comment

Share this Story

Follow Us
Follow I4U News on Twitter
Follow I4U News on Facebook

You Also Like


Read the Latest from I4U News