Rust discovered on the moon

The moon is rusting, and scientists were probably as confused by that conclusion as you were when you read this sentence, writes CNN.

Namely, rust on the moon should not be possible because there is no oxygen there, which is one of the two fundamental things that cause it. The other is water.

But there is evidence for that. India's Chandrayaan-1 lunar probe orbited the Moon in 2008 and collected data that has contributed to many discoveries to date, including the existence of water molecules on its surface.

The probe was also equipped with an instrument produced by NASA with the aim of analyzing the mineral composition of the Moon.

Researchers from NASA and the Hawaiian Institute for Geophysics and Planetology recently analyzed some more data and were "amazed" when they found traces of hematite, a form of iron oxide, or rust. There are many iron-rich rocks on the moon, but rust is only formed when iron is exposed to oxygen and water, Hina agency reports.

"At first I couldn't believe it, because, given the conditions on the Moon, rust shouldn't be there," said Abigail Freeman, a NASA scientist.

Not only is there no oxygen on the Moon, but it is flooded with hydrogen, which flows there from the Sun carried by the solar wind. Rust occurs when oxygen removes electrons from iron, and hydrogen does the opposite, adding electrons to it. That is why rust is difficult to form in areas rich in hydrogen.

"It's very puzzling," said Shuai Le of the University of Hawaii, lead author of the study published in the journal Science Advances.

"The Moon is a terrible environment for hematite formation".

After months of research, Li and NASA scientists think they have solved the puzzle. The culprit for the rust on the moon is - the Earth.

Their first major clue was the fact that most of the rust was concentrated on the side of the Moon facing Earth, which indicated that the phenomenon was somehow connected to our planet.

The Earth is surrounded by a magnetic field, and the solar wind stretches it and creates a long magnetic tail in the direction of the wind. The moon enters that tail three days before it is full and takes six days to come out the other side, reports Hina.

Li believes that oxygen from the Earth reaches the Moon with that magnetic tail and there, in contact with water molecules, it creates rust.

At the same time, during the full Moon, the magnetotail blocks all the solar wind, which means that the Moon is temporarily protected from the impact of hydrogen from the Sun. This also opens up a window of time for rust to form.

But that theory has several "holes". For example, a smaller part of rust was also found on the dark side of the Moon, where oxygen from Earth can hardly reach, and the interaction of water molecules and rocks on the Moon remained unclear.