The Moon is Quaking as it Shrinks

https://www.umdrightnow.umd.edu/news/moo...it-shrinks

EXCERPT: In 2010, an analysis of imagery from NASA’s Lunar Reconnaissance Orbiter (LRO) found that the moon shriveled like a raisin as its interior cooled, leaving behind thousands of cliffs called thrust faults on the moon’s surface. Now a new analysis suggests that the moon may still be shrinking and actively producing moonquakes along these thrust faults. [...] Although the Apollo instruments recorded their last quake shortly before the instruments were retired in 1977, the researchers suggest that the moon is likely still experiencing quakes to this day. A paper describing the work, co-authored by Nicholas Schmerr, was published in the journal Nature Geoscience on May 13, 2019.

“We found that a number of the quakes recorded in the Apollo data happened very close to the faults seen in the LRO imagery,” Schmerr said, noting that the LRO imagery also shows physical evidence of geologically recent fault movement, such as landslides and tumbled boulders. “It’s quite likely that the faults are still active today. You don’t often get to see active tectonics anywhere but Earth, so it’s very exciting to think these faults may still be producing moonquakes.” (MORE)

When they say ‘still be shrinking’ does that mean the moon was larger in the past and if so by how much?

Is the Earth shrinking too?

(May 15, 2019 12:29 PM)Zinjanthropos Wrote: When they say ‘still be shrinking’ does that mean the moon was larger in the past and if so by how much?

Some estimates are that the Moon has shrunk by 600 feet (182 meters) since its formation or settled stage of being non-molten.

Quote:Is the Earth shrinking too?

There's an obsolete theory which carried that idea. There doesn't seem to be any positive developments since in determining that it has.

I think that shrink is the wrong term, Condense would likely be a better one. Consider that gases when combined within a gravitational field condense together to form liquids and solids, it could therefore be hypothesised that initially our planet was likely similar to a gas giant, it's just over time it's condensing and layering shaped the planetscape. (separation of lighter elements from heavier ones, applying them into atmosphere, liquids and of course solids.)

I'd assume it would be far more volcanic, with plumes of ash, sulphur and various heavy gases clouding the skies (I doubt in the planets early life did it worry about CO2 emissions) eventually it would condense and separate into deposits.