If it were a little bigger it might serve as a banana boat.

Cue the Jaws theme.

For the last two months, something has been moving in the waters between St. Thomas and St. Croix, surfacing occasionally to take its bearings. No, Nessie hasn't moved to warmer climes. By all indications, it may not stop until some still undetermined date 4 months from now. (My best guess is sometime between the Ironman Triathlon and the cheerfully-named Optimist Regatta.)

The Woods Hole Oceanographic Institute says the mysterious object is actually a prototype thermal glider on a “green-powered mission.” The power source is so green, it's arguably blue.

According to the WHOI, the glider uses the ocean's temperature differences to get around. Up near the surface, the sun-warmed waters heat wax-filled tubes in the engine. The heat energy generated changes the glider's buoyancy and makes it sink. Down there, the cooler ocean waters reverse the cycle and send the glider back up.

According to the WHOI release, one of the researchers who worked on the glider wrote a sci-fi story about it. Said story appeared in the journal Oceanography and featured a fleet of the gliders patrolling the oceans.

Unsurprisingly, the glider’s field test in the Caribbean is partly funded by the U.S. Office of Naval Research.