Exciting news from a few days ago: While launching another Dragon supply capsule to the International Space Station, SpaceX accomplished a rather novel feat: After detaching from the payload, the booster stage of the rocket was able to descend under its own power and make a (relatively) gentle landing in the Atlantic Ocean.
The booster stage of the rocket is an expensive piece of hardware which is normally jettisoned and rendered pretty unusable either by the heat as it falls back through the atmosphere, or by the sudden stop when that fall is finished. This is a pretty big part of why space flight is so expensive with our current technology: Rockets are expensive, and at this point in time most of them have been single-use only. If you had to buy a new car (or even new tires) every time you drove anywhere, you would probably not do very much driving.
SpaceX plans to change that. They’ve equipped some booster rockets with landing legs, and their ultimate goal is to have them set themselves right back down on the launch pad. This pretty amazing video demonstrates what they have in mind:
If boosters could land this way, it could be very cheap and easy to simply refuel them and give them a new payload and send them up again in a short period of time. A rocket launch pad could start to look more like an airport gate or a shipping terminal and less like a perpetual construction site. And that could give a pretty big boost (heh) to other space businesses, such as Planetary Resources. Elon Musk, SpaceX’s CEO, has a stated goal of enabling the colonisation of Mars, and while that’s still pretty far off, you can’t fault him for lack of effort.