The eastern basin of the moon as seen by NASA’s Lunar Reconnaissance Orbiter. Credit: NASA GSFC
Billions of years ago, a series of volcanic eruptions wreaked havoc on the Moon, covering hundreds of thousands of square miles of the orb’s surface with hot lava. Over the years, this lava created dark spots, or maria, which give the face of the moon its characteristic appearance today.
Now, new research from the University of Colorado Boulder (CU Boulder) suggests that volcanoes may have left another lasting impact on the lunar surface: sheets of ice that punctuate the moon’s dust and, in some places, could measure dozens. or even hundreds of feet. thick.
“We imagine it as a frost on the moon that has accumulated over time,” said Andrew Wilcoski, lead author of the new study and a graduate student in the Department of Astrophysics and Planetary Sciences (APS) and the Atmospheric Physics Laboratory. Spatial. (LASP) and CU Boulder.
He and his colleagues published their findings this month in The Planetary Science Journal.
Scientists believe that the Schroeter Valley as a moon snake was created by lava flowing to the surface. Credit: NASA Johnson
Researchers relied on computer simulations, or models, to try to recreate conditions on the Moon long before complex life arose on Earth. They discovered that the ancient volcanoes of the moon emitted large amounts of water vapor, which then settled on the surface, forming ice deposits that could still be hidden in lunar craters. If a human being had been alive at that time, he might have even seen a piece of that frost near the border between day and night on the surface of the moon.
It is a potential reward for future explorers of the moon who will need water to drink and turn it into rocket fuel, said study co-author Paul Hayne.
“At 5 or 10 feet below the surface, you may have large sheets of ice,” said Hayne, an assistant professor at APS and LASP.
Temporal atmospheres
The new study adds to a growing body of evidence suggesting that the moon may be flooded with much more water than scientists believed. In a 2020 study, Hayne and colleagues estimated that about 6,000 square miles of the lunar surface could be able to catch and hang on ice, especially near the north and south poles of the moon. First of all, it is not clear where all this water came from.
“There are a lot of potential sources right now,” Hayne said.
Volcanoes could be large. The planetary scientist explained that between 2 and 4 billion years ago, the moon was a chaotic place. Tens of thousands of volcanoes erupted on its surface during this period, generating huge lava rivers and lakes, similar to the features you might see in Hawaii today, but much more immense.
A representation of how ice could have formed on the surface of the Moon billions of years ago. Credit: Paul Hayne
“They undertake almost every eruption on Earth,” Hayne said.
Recent research by scientists at the Lunar and Planetary Institute of Houston shows that these volcanoes probably also emitted high clouds made up primarily of carbon monoxide and water vapor. These clouds revolved around the moon, potentially creating thin, short-lived atmospheres.
This made Hayne and Wilcoski wonder: Could the same atmosphere have left ice on the lunar surface, a bit like the frost that forms on the ground after a cold autumn night?
Ice forever
To find out, the duo along with Margaret Landis, a researcher associated with LASP, set out to try to land on the moon’s surface billions of years ago.
The team used estimates that, at its peak, the Moon experienced an eruption every 22,000 years, on average. Researchers then tracked how volcanic gases may have orbited the Moon, escaping into space over time. And, they found out, the conditions may have been frozen. The group estimates that about 41% of the volcano’s water may have condensed on the moon in the form of ice.
“The atmosphere escaped for about 1,000 years, so it took a long time for ice to form,” Wilcoski said.
In fact, there may have been so much ice on the moon that you could possibly have seen the glow of the frost and the thick polar caps of the Earth. The group estimated that about 18 trillion pounds of volcanic water could have condensed as ice during this period. It’s more water than Lake Michigan currently has. And research indicates that much of this lunar water may still be present today.
These space ice cubes, however, will not necessarily be easy to find. Most of this ice has probably accumulated near the poles of the Moon and may be buried under several feet of lunar or regulated dust.
One more reason, Hayne said, for people or robots to go back and start digging.
“We really need to dig deeper and look for it,” he said.
Reference: “Polar Ice Accumulation from Volcanically Induced Transient Atmospheres on the Moon” by Andrew X. Wilcoski, Paul O. Hayne and Margaret E. Landis, May 3, 2022, The Planetary Science Journal.DOI: 10.3847 / PSJ / ac649c