In a new paper in Nature Astronomy, a team from Osaka University publishes its analysis of data gathered by the Japan Aerospace Exploration Agency's Selenological and Engineering Explorer, revealing that an isotope present in lunar regolith is a match for an isotope found in terrestrial, atmospheric oxygen.
The authors hypothesize that the Earth's magnetic tail brings charged particles from the Earth to the Moon.
The ions get out of the Earth's atmosphere because when sunlight or the occasional cosmic ray hits atoms of oxygen (or any other gas) at the edge of space, those atoms can lose an electron, becoming charged. Earth's magnetic field captures the resulting ions, and some get flung out into space.Terada told Space.com that the evidence for where the ions came from was the isotope oxygen-16. Earth's upper atmosphere and the moon have relatively little oxygen-16, whereas the solar wind has more. The lunar soil's oxygen content has three components: One is rich in oxygen-16, and that is from the solar wind. Another is poor in oxygen-16, and it wasn't clear where that came from, until the team looked at the data and compared this component to the ions in Earth's atmosphere.
Biogenic oxygen from Earth transported to the Moon by a wind of magnetospheric ions
[Kentaro Terada, Shoichiro Yokota, Yoshifumi Saito, Naritoshi Kitamura, Kazushi Asamura & Masaki N. Nishino/Nature Astronomy]
Moon's Been Getting Oxygen from Earth's Plants for Billions of Years
[Jesse Emspak/Space]
(via Beyond the Beyond)
