Sky Quality Meter (SQM)

A handheld meter that turns sky darkness into a number. oddly satisfying for people who measure everything outdoors.

This little gadget tells you how dark the night sky is, as a number you can compare from place to place. set it outside, point it up, and use the readout to judge light pollution or decide if a spot might show the milky way. it’s nerdy and oddly calming — useful when you want facts instead of guesses about the sky.