A mirage that appeared to warp the landscape of Glacier Bay National Park and Preserve in Gustavus, Alaska, was captured by the National Park Service.

This video, which Glacier Bay National Park and Preserve said was filmed on June 9 in Glacier Bay, shows the mirage distorting a shoreline and islands.

“Fata Morgana is a mirage seen within a narrow band on Earth’s horizon,” wrote the park on Facebook. “Islands in Glacier Bay turn to UFOs or the flying Dutchman with a little imagination and a pinch of cool science!”

The mirage occurs when air passes through different densities, according to the park, making air in the Earth’s atmosphere act as a reflective lens. Credit: Glacier Bay National Park and Preserve via Storyful