By Erik Hopkins, staff reporter.
What do you think of when you think of the moon? Maybe that it’s made of cheese like you were told once when you were young. Maybe in your head you hear, “That’s one small step for man, one giant leap for mankind.” Thanks, Neil Armstrong.
Our understanding of how the moon was formed could potentially be flipped on its head, according to Kun Wang, a Washington University Geochemist. He found evidence that shows that the moon is actually made from melted Earth matter.
In the article “Proto-Earth May Have Been Significant Source of Lunar Material”, written by Soderman/NLSI Staff and published by NASA,“A giant impact between the proto-Earth and a Mars-sized impactor named Theia is the best current theory for the formation of the Moon.” After the collision with rubble left over, Earth’s rocks were vaporized and melted, and the elements within the rocks turned into gas. When all of Earth’s original pieces cooled and solidified, it created the Earth’s original natural satellite, according to Popular Science, a bi-monthly science magazine.
The magazine says that the temperature starts to decrease with time, the vapor begins to condense, forming liquid moonlet drops.
“The material would eventually coalesce into a disc – something like the rings of Saturn,” says Robin Canup, planetary scientist at the Southwest Research Institute. After the vapor turned into liquid moonlet drops, the moon formed and the rest of these materials fell down to Earth.
Nature, an international weekly journal of science, published Wang’s new analysis where he agreed with Canup’s statement. In Nature, Wang and his co-author Stein Jacobsen examined lunar dust from several different Apollo missions and counted potassium isotopes. In his lunar samples, Wang says he found heavier potassium signatures.
“[The data] reveals the physical conditions during the Earth-shattering event that formed the moon,” Wang told Popular Science. These samples basically show that the heavier material condensed first, which formed the moon.
The new analysis of these potassium isotope levels in lunar and terrestrial rocks allows us to support the high-energy impact there.
“The enrichment of the heavy isotope of potassium in lunar rocks compared with those of the Earth and chondrites can be best explained as the result of the incomplete condensation of a bulk silicate Earth vapour at an ambient pressure that is higher than 10 bar,” says Wang and Jacobsen in Nature.
While there’s nothing extensive yet, this new piece of evidence will allow fresh and improved moon-formation theories, says Canup.