This is perfect sphere of liquid metal, suspended using a strong magnetic field so that it can levitate in space. Oh and it's aboard the International Space Station.
With all things science seemingly colliding in a single image, you'd be forgiven for thinking this was just a case of NASA showing off. But in fact the experiment allows scientists to understand the formation of solid metals while being able to eliminate the effects of gravity and containing structures, which is usually the case down on Earth. The ball is quickly cooled, to understand how the process of quenching metal -- like when ironmongers dip forged swords into cold water, say -- really works. And maybe show off, just a little bit. [New Scientist]