Did you know there are earthquakes on the moon?

These are known as moonquakes and they're are fairly common.
Moonquakes are caused by internal rearrangement of the Moon's orbit, that is because this
it's not a perfect circle, as it has deep imperfections generated by tides, and surface imperfections
whose origin is the expansion of the rocks produced by the heat of the Sun .
Natural moonquakes are originated inside of the lunar globe, and there hace been detected up to four
earthquakes per week, but of two degrees in the Richter scale, so almost not enough to
be earthquakes, tremors alone would almost be imperceptiles by man.
But another curiosity related to this is that moonquakes occur most often when the moon is
at the closest point to the earth, and there are telluric movement that can reach five Richter degrees.