During a 2002 ROV expedition by Japan Agency for Marine-Earth Science and Technology (JAMSTEC) off Sanriku, something unexpected happened at the moment the ROV filmed a squid.
The footage shows something like a fast-moving glowing saucer-shaped object passing by in the background at a depth of 421 meters.
Unable to identify the object, the puzzled expedition members wondered if the ROV (remotely operated vehicle) had captured a deep-sea animal or more likely a UFO/USO (Unidentified Submerged Object).
It's not the first time USOs like this have been seen in Earth's bodies of water. These UFOs/USOs flying into and out of the oceans, unknown craft that are able to travel underwater at a tremendous speed but till now it remains a mystery what exactly these objects are and where they come from.