How do they make zero gravity effects in movies?

Technology is advancing faster than ever these days, and one movie lately left me wondering; how the heck do they do it? After watching the movie Gravity, the story of two shuttle astronauts hurtled through space by a space disaster, I couldn't figure out how they made Sandra Bullock and George Clooney float effortlessly for the entire two hours of filming. The movie takes place in space, not just snippets and parts, but the entire movie. "There's no way this movie was filmed in space," I thought to myself, and there was no way the actors agreed to film it free-falling from below the atmosphere in a 747, known as parabolic airplane flights, which is usually how they film plane dives and  those short, action filled gunfights you see in the James Bond movies. One of the recent movies that uses this type of filming was Apollo 13, which only allows about thirty seconds of zero gravity at a time (unless you want about two-minutes worth which will also include a dramatic crash landing). This wasn't an option, however, because thirty seconds was not near long enough for all the shots needed for the film, and also Sandra Bullock is deathly afraid of flying.

It turns out, the movie was filmed using a "light box", or a huge contraption that the actors sit in which is made up of thousands of LED lights. These lights produce high-definition moving images that spin around a motionless actor to make it seem as if they are spinning. This is how they were able to portray the enormous planet Earth in the background while Bullock was being thrown through space. The actors sit on small pedestals while the light box displays different images around them. The actors were also in a harness for some scenes free floating, while they had green cords and strings attached to some parts of their body like a human puppet. They were then controlled by puppeteers who made their arms and leg move. When the actors were locked up inside the light boxes, computer-controlled robotic cameras captured close-ups under just the right lighting conditions — even for the scenes where Bullock looks as if she's spinning out of control. In reality, it's the light patterns that are spinning around her. 

Click the link below to see a behind the scenes video on how the movie was filmed using the light box!
http://www.dailymotion.com/video/x18svz7_gravity-behind-the-scenes_shortfilms

GEORGE CLOONEY DIES.

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