content: It was a 'standard' cargo mission to the International Space Station - NASA have contracted billions out to a private company called SpaceX owned by Elon musk to ferry food, oxygen and water (and other stuff). The idea is that rather than building spaceships for mundane tasks, NASA give money to these private companies to do it instead, meaning that NASA can focus on building the next gen space shuttle replacement.  SpaceX have done 6 successful deliveries (all unmanned) and are starting to test the tech needed to 'convert' their ship to a manned version. But it's more amitious than that - they want to make a fully reusable rocket to bring cost down. So, this launch, CRS 7, was another unmanned cargo run to the space station, with a secondary goal of landing the first stage of the rocket (the massive rocket itself) on a barge in the ocean. The whole thing blew up.