The Moon has moonquakes — and some last for over 10 minutes
NASA's Apollo missions left seismometers on the Moon, which recorded thousands of moonquakes. Unlike Earth, which dissipates seismic energy quickly through water and fragmented rock, the Moon's dry, cold, rigid structure means vibrations can ring for 10–30 minutes — far longer than any earthquake. There are four types: deep moonquakes (700km below the surface, probably tidal), shallow moonquakes (30–50km, cause unknown), thermal quakes (surface contractions), and meteorite impacts. The Moon is far more seismically active than was expected before Apollo.
We think of the Moon as a dead, inert rock — a passive companion. Finding it's seismically active, that quakes ring through it for half an hour, and that we don't fully understand the cause of some of them gives the Moon an unexpected interior life.
“The Moon has moonquakes that can last over 10 minutes. Because the Moon is cold and dry, it 'rings' like a bell instead of absorbing seismic energy quickly the way Earth does. 🌕 #OddlyHuman”