Inside the Japan Aerospace Exploration Agency's (JAXA) Kibo lab on the Earth-orbiting Internatational Space Station, NASA astronaut Tom Marshburn conducts a session of the ongoing SPHERES-VERTIGO investigation. SPHERES stands for Synchronized Position Hold, Engage, Reorient Experimental Satellites. Each satellite is an 18-sided polyhedron that is 0.2 meter in diameter and weighs 3.5 kilograms. The prism-shaped device (called Goggles) which is hooked up to the red or forward-most polyhedron in the picture is called Visual Estimation and Relative Tracking for Inspection of Generic Objects (VERTIGO).