By Cassie Kelly, June 18, 2015
NASA has been keeping their eye on some very rare cloud formations, and people in the northern half of the North Hemisphere may get a glimpse, according to Bloomberg News.
The Aeronomy of the Ice in the Mesophere satellite mission has studied these cloud formations, known as noctilucent clouds, for eight years. Though the scientists are unsure of their exact cause, methane and carbon dioxide emissions could be altering the mesosphere where these clouds form.
Increases in methane, carbon dioxide and water vapor high in the atmosphere cools temperatures in the mesosphere. NASA says these clouds are a direct indicator of modern-day climate change, especially because they’ve only been visible for the past century.
The clouds usually appear in the spring. This year they started showing up on May 19 and are expected to peak on June 21.