Sky Quality Meters FAQ

What is a Sky Quality Meter (SQM)?

A sky quality meter (SQM) is an instrument used to measure the luminance of the night sky. It is used, typically by amateur astronomers, to quantify the skyglow aspect of light pollution and uses units of "magnitudes per square arcsecond" favored by astronomers.

How do I set up and install a Sky Quality Meter (SQM?)

What is the best location to install an SQM?

In rural locations, city locations and in between. All locations provide useful data! If you’re interested in becoming a volunteer and managing a Sky Quality Meter, please contact us.

How many SQMs are currently installed around Oregon?

There are currently 43 Sky Quality Meters installed around Oregon, with another 15 locations in discussion. You can see the latest map on our Measuring the Night Sky’s Brightness page.

What will you do with the SQM data I share with you?

The data provided will be used to analyze the overall night brightness in Oregon and be published on a semi-annual basis as part of our Oregon Skyglow Measurement Network - Technical Report. The last report was published in March 2023.