The photograph taken by Leesa Willmott on her smartphone Monday over Wonthaggai, Australia, might look like a giant UFO is displacing cloud or using an invisibility cloak of sorts, but meteorologists say it's actually the result of a natural, yet rare, phenomenon.
The bizarre sight above the town near Melbourne is called a fallstreak hole.
Adam Conroy, a forecaster with the country's Bureau of Meteorology, said fallstreak holes are circular gaps that appear when a section of the cloud freezes. The ice crystals are heavy, so they fall out of the cloud, leaving a hole.
The U.S. National Oceanic and Atmospheric Administration's office out of Wisconsin recently detailed the phenomenon as well. It added that this formation usually happens in high to mid-level clouds, like altocumulus. Check out NOAA's website for more photos of fallstreak clouds.
The Associated Press contributed to this report.