NASA Discovers the Moon Once Had an Atmosphere
You might think we've learned everything there is to know about the moon, but you'd be wrong.
It's common knowledge that the large moon that orbits our planet (the big one, not the newly discovered tiny second moon) is an empty, barren wasteland of dust and rock.
As this is the present appearance of the lunar surface, it's easy to believe the moon has always existed in this state: dead and lifeless, wrapped completely in the crushing vacuum of space.
However, this wasn't always the case. Once upon a time, the moon experienced huge volcanic activity as it churned and bubbled with basalt and other chemicals.
According to a new study from NASA, at one point the moon even had its own atmosphere, thanks in large part to volcanic eruptions.
This environment wouldn't exactly be comfortable to experience, though.
In the study published in Earth and Planetary Science Letters, Dr. Debra H. Needham and Dr. David A. Kring explain that the atmosphere was comprised of gasses that were released by the moon's volcanoes, most notably carbon monoxide, along with other materials such as water vapor and sulfur.
This wasn't a recent occurrence - the moon's atmosphere would have formed at some point during the greatest period of lunar volcanic activity, around 3.5 billion years ago, before the giant rock cooled and settled down. The atmosphere of deadly gasses would have remained around the planet for approximately 70 million years, before dissipating.
Where did the atmosphere go?
Well, thanks to the moon's weak gravity, these gasses would have basically just floated off into space over time, leaving an empty, cold rock and little else.
What's particularly interesting about the lunar volcanic activity is that it explains why the moon looks the way it does to us on Earth.
The speckled appearance, with dark patches and circles that either form a dog or a face, depending on where you're viewing it from, is actually the result of basalt that was kicked up during volcanic eruptions. These lakes of basalt still remain on the surface of the moon all this time later, despite having initially formed back when the lunar rock was brand new and still piping hot.
There's little danger of a new era of volcanic eruption on the moon, and currently planned colonies probably won't run into any trouble from toxic gasses when they finally get set up.
Whereas the Martian surface has recently been proved to still be volcanically active, albeit very, very slowly, the moon is now completely stagnant, and the fear of future lava plumes and carbon monoxide belches won't be bothering any colonists who head to the moon in the near future.
That said, the moon's surface is hardly free from other dangers.
There may not be volcanoes to contend with, but future colonists will hardly be having a Hawaiian vacation up there.