The moon should probably have no rust.
Rust, an iron oxide, requires both oxygen and water to occur naturally. So one might think that the moon - a celestial body that is mostly dry and does not contain oxygen - has no rust at all. But it turns out that it is. And scientists are trying to find out why.
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A new study published in Science Advances took data from Chandrayaan-1 orbiter of the Indian space research organization and discovered that the rock at the poles of the moon had a different composition than other areas of the moon. Upon closer inspection, lead author Shuai Li discovered hematite, essentially a common iron oxide rust.
He reached out to scientists and the NASA Jet Propulsion Laboratory to confirm the find.
"At first I didn't believe it at all. It shouldn't exist based on conditions on the moon," said JPL scientist Abigail Fraeman, one of the scientists Li contacted. "But since we discovered water on the moon, people have speculated that there could be a greater variety of minerals than we believe if that water had reacted with stones."
Why is there rust on the moon right now? There are a number of factors, but the earth is partly to blame.
First of all, water exists in small quantities on the moon. Ice water exists in lunar craters, but that water exists on the other side of the moon, far from where the rust occurred. The current theory is that dust particles, which frequently hit the moon, help release water molecules and mix these water molecules with iron on the surface.
Then there is the percentage of oxygen. This is where the earth comes in.
Thanks to the fact that it exists in such close proximity to Earth, the moon hosts amounts of oxygen that travel from the upper atmosphere of the earth to the moon. Li found that the side of the moon that faces the earth has more rust than the areas that do not face the earth.
He believes this process has been going on on the moon for billions of years. Moon, please accept our sincerest apologies for the rust.
