Did the Moon’s geological activity stop billions of years ago after it formed, or has it been active since then? This is what a recent study published in The Planetary Science Journal hopes to address as a team of researchers investigated specific features on the Moon’s surface that could challenge longstanding hypotheses regarding the Moon’s geological history. This study has the potential to help scientists better understand the formation and evolution of our Moon, which could shed new light on the formation and evolution of the Earth.
For the study, the researchers used a common technique called crater counting to analyze newly discovered ridges on the Moon’s far-side, the latter of which constantly faces away from the Earth due to the two planetary bodies being tidally locked with each other. Crater counting is used to determine the relative age of a planetary body’s surface, and the researchers were trying to ascertain the age of the ridges on the far-side of the Moon. The reasons ridges are so intriguing is due to their potential formation when the Moon shrank in size after it cooled down.
In the end, the researchers discovered that these ridges were far younger than previous ridges found on the far-side of the Moon, especially since the far-side of the Moon is much older than the near side of the Moon. These findings also raise questions regarding the Moon’s geological activity history.
Image of a mare ridge located near the Aitken impact crater on the far side of the Moon. (Credit: Smithsonian Institution, University of Maryland)
“Many scientists believe that most of the moon’s geological movements happened two and a half, maybe three billion years ago,” said Dr. Jaclyn Clark, who is an assistant research scientist in the University of Maryland’s Department of Geology and a co-author on the study. “But we're seeing that these tectonic landforms have been recently active in the last billion years and may still be active today. These small mare ridges seem to have formed within the last 200 million years or so, which is relatively recent considering the moon’s timescale.”
Better understanding the geological history of the Moon could help shed light on the Earth’s evolution, specifically regarding how the ridges identified on the far-side of the Moon in this study share similar structures as ridges found on the near side.
What new discoveries about the Moon’s geological activity will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: The Planetary Science Journal, EurekAlert!, University of Maryland
