If you looked up in the northern sky Saturday night, you may have caught a glimpse of what appeared to be the “Northern Lights.” They were actually “noctilucent clouds.”
These clouds form in the higher latitudes, and about 50 miles in the sky. They form in the mesosphere.
The clouds are made up of ice crystals, which reflect the twilight just after sunset near the horizon. Temperatures that high up in the atmosphere are very, very cold (we are talking colder than -180°F).
While not always visible in Iowa, the most frequent time these clouds can be seen are during late spring and summer.
Photo credit: Jessica Schroeder from Dike.