Ceilometer

Okay kiddo, so a ceilometer is kind of like a really fancy ruler that measures how high clouds are in the sky. You know when you look up and see clouds? Well, some people need to know exactly how high those clouds are, and that's where a ceilometer comes in.

It shoots a little laser beam up into the sky and measures how long it takes for the light to bounce back off of the clouds. Then it does some math to figure out how far away the clouds are, and how high they are from the ground.

People who use ceilometers can use this information to figure out things like the weather and the air quality. So even though it's just measuring clouds, it's actually really important!