Bizzare Facts

We tend to think of the **Moon** as a dead, silent rock floating in the vacuum of space, geologically inactive for billions of years. However, data from the Apollo missions tells a different story. Between 1969 and 1977, seismometers placed on the lunar surface by astronauts recorded thousands of seismic events, which scientists call **moonquakes**. The Moon is actually humming with seismic activity, although the causes are quite different from those on Earth.

On Earth, earthquakes are primarily caused by the grinding of tectonic plates. The Moon doesn't have active plate tectonics. Instead, deep moonquakes are caused by **tidal stresses**—the immense gravitational pull of the Earth stretching and squeezing the Moon as it orbits. Essentially, our planet is kneading the Moon like a ball of dough, causing deep cracks to slip and rumble. Other quakes are caused by meteorite impacts or the thermal expansion of the frozen crust when the sun rises.

One fascinating difference is the duration. An earthquake on Earth usually lasts less than a minute because the water in our crust dampens the vibrations. The Moon, however, is bone dry and rigid. As a result, a moonquake causes the entire celestial body to ring like a bell. The vibrations can continue for up to **an hour** or more, echoing through the stone. It’s a haunting reminder that even the 'dead' worlds above us are still moving and shaking.