WESTBROOK, Maine — Think of it as a crop circle, but in a river.
A curious formation that has grabbed the attention of Greater Portland, Maine, is actually a spinning ice disk, and it's roughly 100 yards wide.
The formation in the Presumpscot River was widely shared on social media, and it has drawn comparisons to an alien spacecraft, a carousel and the moon.
Rob Mitchell, who owns a nearby office building, spotted the alien-looking disk Monday morning and immediately notified the city of Westbrook, just outside Portland. Officials say the disk is spinning slowly counter-clockwise, and has served as a big raft for ducks and other birds.
Mitchell says "the ducks were rotating on this big Lazy Susan."