Name: SpaceX的危险可重复使用火箭发射（SpaceX's Risky Reusable Rocket Launch）
Uploaded: 2021-04-18T14:36:05.000Z
Duration: 3 min 48 s
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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.

程度副詞

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

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

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

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.

land in a specially-designed rocket called the Grasshopper.

In 2012 and 2013 the grasshopper made eight hops

and landing safely on the ground each time.

The concept proved promising but still needed to be tried

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

turns out that the Atlantic ocean isn't the most friendly place

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

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 --

isn't much bigger than the rocket itself.

SpaceX says that there is a high chance of failure.

But you gotta give them credit for even getting this far.

to reusable rockets and a much more accessible space travel.

Thanks for watching this SciShow Space News

If you wanna keep exploring the universe with us