If something goes wrong with the upcoming space shuttle replacement program, and we hope it does not, this is what could save the astronauts' lives. As they hurtle hundreds of miles per hour into the heavens, and their ship begins to break apart, mission control will scream "ABORT!" (or perhaps something a bit more technical), and the astronauts will be ejected from the capsule with a force that's actually much greater than the g's they'll experience during launch.
What you're seeing above is a test of this new ejector seat system, dubbed the Launch Abort System. It burns through half of its fuel in three seconds flat, NASA says, but then again if you're escaping from an exploding, disintegrating tin can filled with jet fuel, that's kind of the idea.
Fun fact: Like much of the Orion capsule/Areas rocket program, this ejector seat is also an example of NASA going back in time to deliver tomorrow's explorers to the moon. In the seat's case, the Apollo program's old-school abort system is the inspiration. [Wired]