Traces of Earth

While researchers have known for years that oxygen can be found on the Moon, a Japanese spacecraft has detected lunar samples of the element with a very interesting origin: Earth.

The discovery was made by the SELENE (Kaguya) spacecraft, and a team led by planetary scientist Kentaro Terada of Osaka University in Japan reported the findings in Nature Astronomy.

Not only does the team believe the discovery could shed light on our planet’s creation billions of years ago, including the state of its early atmosphere, they also have a theory on how Earth’s oxygen made it to the Moon.

For about five days every month, the Moon is shielded from the Sun’s solar winds by Earth’s magnetosphere — a bubble-like region in which Earth’s magnetic field has considerable influence. The researchers believe oxygen ions slowly made their way from the Blue Planet to the Moon during this brief respite and became embedded in the Moon’s loose top layer of soil and rock.

Our Future with the Moon

Geologic activity on Earth has erased evidence of our ancient atmosphere. However, these oxygen ions on the Moon could remain embedded for billions of years. Therefore, collecting samples of this displaced oxygen could help researchers understand how Earth’s atmosphere has changed over time and how much of an influence these changes had on the evolution of various forms of life.

In addition to helping us understand the Earth’s past, such research could also help us in efforts to colonize space. We do need oxygen to breath, after all, and the Moon seems to be the most likely colonization destination based on the number of plans in the works: Japan aims to put another astronaut on the Moon by 2030, Amazon CEO Jeff Bezos believes it’s time for us to permanently settle there, and the United Arab Emirates (UAE) has its own plans for a Moon colony.

Retired astronaut Chris Hadfield thinks Moon colonization is the most logical next step after putting people in orbit and having them walk on the Moon. “I think if we follow the historically driven pattern, then the Moon would be first [before Mars],” said Hadfield in an interview with New Scientist. “Not just to reaffirm that we can get there, but to show that we can also live there.”

We won’t know for several years whether or not the Moon becomes our first off-world home, but regardless of humanity’s colonization plans, the undeniable truth is that we’re not done learning about our natural satellite just yet.