If you ever spent a lazy afternoon lying on the grass and looking at cloud formations, you’ve probably already seen all kind of amazing cloud shaped dragons, dogs and dinosaurs. However, this time twitter user @pmxpvrtmx (Poppy) has captured a perfectly spherical one floating above houses in Fujisawa, a city in Kanagawa Prefecture, Japan.

“When I looked out of the car window I saw a round ball-shaped cloud. I gazed at the cloud for a while then I rushed to take the photo. When I saw the cloud it was an even more spherical shape, so I regret not taking the photo more quickly,” – she wrote on twitter.

Some climate experts commented that this cloud probably falls under a “roll cloud” category. It “forms under wind created from a ‘mountain wave’ (or airstreams going over mountains) on a windy day”. According to Wikipedia “roll clouds are formed by outflows of cold air from sea breezes or cold fronts.”