NASA has started testing its new Buoyant Rover for Under-Ice Exploration (BRUIE) prototype, and as you can see above, it looks markedly different from its predecessor. It's taller, thicker, has rotating segments to be able to take pictures from different directions and can withstand depths up to 700 feet. This prototype also has communications equipment and sensors similar to those used for Mars Cube One. That's the communications CubeSat slated to escort the InSight lander to the red planet. The agency recently put the new BRUIE to the test for a few days inside a 188,000-gallon tank at the California Science Center, where it spent its time taking photos of tropical fish. It was attached to a corner and didn't have its wheels in the aquarium, but it'll most likely get them back for its next test run near one of the planet's poles.