• A new study suggests that Earth’s Moon may have been vital to the protection of Earth’s atmosphere early on in its development. 
  • A sort of “lunar shield” may have protected the atmosphere long from the Sun, giving life on Earth the opportunity to take root.
  • Missions to the Moon in the coming years could prove this theory correct.

Thanks to the incredible work of scientists around the world, we know a lot about how life took root here on Earth. We know that a combination of water, heat, and maybe even impacts from extraterrestrial objects likely played a role in taking the building block of life and turning them into something more. However, a new study suggests that the Moon may have played a pivotal role in maintaining Earth’s habitability in those very early days.

Earth wasn’t always habitable, of course. It started out as a volatile rock with very little in terms of life-supporting resources. The Sun’s intense radiation may have threatened to degrade Earth’s atmosphere to a point that life could never catch on, but the Moon, as it turns out, may have helped a lot.

In a new research paper published in Science Advances, researchers led by a team at NASA explore the likelihood that a shared magnetic field between the Earth and its Moon provided extra protection for our planet’s atmosphere and allowed it to remain robust enough to support life.

“The Moon seems to have presented a substantial protective barrier against the solar wind for the Earth, which was critical to Earth’s ability to maintain its atmosphere during this time,” NASA’s Jim Green, lead author of the study, said in a statement. “We look forward to following up on these findings when NASA sends astronauts to the Moon through the Artemis program, which will return critical samples of the lunar South Pole.”

Using computer simulations to paint a clearer picture of what the relationship between the Earth and Moon was like some four billion years ago, the team was able to demonstrate how the Moon’s magnetosphere could have provided a sort of shield against the harsh outflow of material from the Sun.

“Understanding the history of the Moon’s magnetic field helps us understand not only possible early atmospheres, but how the lunar interior evolved,” NASA’s David Draper, co-author of the study, explains. “It tells us about what the Moon’s core could have been like — probably a combination of both liquid and solid metal at some point in its history — and that is a very important piece of the puzzle for how the Moon works on the inside.”

Once the crewed Artemis missions begin in 2024 (or shortly thereafter, if NASA can’t nail the incredibly ambitious date set forth for it by the Trump administration), we’ll get a better idea of how the Moon may have affected and protected the young Earth. We may even find out that we owe our lives, and the lives of everything on the planet, to our pale white protector.

Mike Wehner has reported on technology and video games for the past decade, covering breaking news and trends in VR, wearables, smartphones, and future tech. Most recently, Mike served as Tech Editor at The Daily Dot, and has been featured in USA Today, Time.com, and countless other web and print outlets. His love of reporting is second only to his gaming addiction.