字幕列表 影片播放 列印英文字幕 Private space flight has had kind of a bad year between the failure of Orbital Sciences cargo rocket in Virginia And the tragic loss of SpaceShip 2's pilot Michael Alsbury. But leave it to our not so secret braincrush Elon Musk The head of SpaceX to take private space exploration to a whole new level The new level in this case being the surface of the ocean. On Friday, December 19th, 2014, SpaceX will launch one of it's Falcon 9 rockets into space Loaded with more than fifteen hundred kilograms of supplies and experiments for the International Space Station But after the first few minutes of flight, instead of just crashing back to earth like it usually does, the rocket's first stage will gently touch down on a platform floating in the Atlantic Ocean. At least, that's the plan. Getting something into orbit is complicated, so the Falcon 9 launch system uses two main stages. The first stage is the most powerful one with nine engines burning liquid oxygen and kerosene for up to three minutes. Then, so that it doesn't have to drag all that extra mass into orbit, it separates and the second stage takes over with just one engine propelling the cargo into orbit. Normally, rockets like these are a one-time-use kind of deal and each one costs about a hundred million dollars. Since you have to build a new one every time you wanna get off the planet, space travel is really, really expensive! It costs more than twenty thousand dollars for every kilogram of cargo your carry into orbit so, in 2011 Musk announced his company's goal to build a reusable rocket that would make space travel less costly. Eventually the company plans to develop a whole system that is entirely reusable but it's focusing on the first stage, for now. The plan for this week's mission is to have some fuel remaining in the tank in the first stage when it separates. Then it'll fire three of its nine engines to slow itself down and a control system will be deployed with special grid fins to help prevent the rocket from going into a spin and keep the engines pointed in the right direction. Once it gets close to the landing platform, four landing legs will deploy and the central engine will fire, letting it basically settle into a soft landing, as opposed to usual hard landing where everything gets blown to bits. This system was first tested over land in a specially-designed rocket called the Grasshopper. In 2012 and 2013 the grasshopper made eight hops reaching altitudes of up to 744 meters and landing safely on the ground each time. The concept proved promising but still needed to be tried on a Falcon 9 during an actual launch of which it was tested over the ocean three times. The plan was for the rocket to make a soft landing right on the surface of the ocean and then tip over so that it would float over the water horizontally In the first test in September 2013, the rocket went into a spin and the engines failed : ( During the next two tries in April and July of 2014 the system succeeded in slowing the first stage down before it hit the water but it turns out that the Atlantic ocean isn't the most friendly place to land. During the first test, the rocket was torn apart by rough seas and the second, it hit the water too hard when it tipped over and in the words of Elon Musk, went 'KABOOM.' But this Friday's test flight will be different because the rocket won't be landing in the water -- exactly. Instead SpaceX has built a landing platform for it with the totally boss name of 'Autonomous Spaceport Drone Ship.' Keeping this platform in one place is going to be tricky, so with GPS as its guide, the drone ship will use four thrusters to make sure that it doesn't move more than three meters -- even during a storm. That's important because at 91 by 52 meters, the platform isn't much bigger than the rocket itself. Since this is the first test of its kind SpaceX says that there is a high chance of failure. But you gotta give them credit for even getting this far. If it works, we will be well on our way to reusable rockets and a much more accessible space travel. If not, we'll still be one step closer. Thanks for watching this SciShow Space News If you wanna keep exploring the universe with us you can go to youtube.com/scishowspace and subscribe!