Google X, the secretive moonshot lab run under Google’s parent company Alphabet, wants to make the internet accessible for everyone.
That’s why Google has been refining its giant, internet-beaming balloons since 2013 as part of its Project Loon. But to make that vision a reality, Google has gotten some outside help from Raven Aerostar, a hot air balloon manufacturer, to help create the balloons.
Scroll down to see how Google makes its Project Loon balloons.
The goal of Project Loon is to use a network of solar-powered balloons to beam broadband to areas without internet access.
The balloons fly high in the stratosphere at about 60,000 to 90,000 feet above Earth. That's two to three times as high as most commercial aeroplanes.
Raven Aerostar creates a special outer shell for the balloons, called the film, that can hold a lot of pressure -- allowing the balloons to float in the stratosphere for longer.
The film is as thin as a typical sandwich bag.
'It's one of the most critical components of a balloon,' Scott Wickersham, general manager at Raven Aerostar, told Tech Insider. 'The film is what holds the helium in there. And if you put too much pressure or if the film isn't strong enough, the balloon will burst.'
The film is made of a special formulation of polyethylene that allows it to retain strength when facing extreme temperatures of up to -112 degrees Fahrenheit.
Project Loon actually tests the balloons at McKinley Climatic Lab in Florida, which creates the sub-freezing environment the balloons will actually fly in. They have even recorded the conditions that would cause a balloon to burst using high-speed cameras to better prepare the balloons for the frigid environment.
The balloons also have an internal chamber called a ballonet that will determine how high the balloons fly.
'So a blower will literally blow air from the atmosphere and blow it into the the ballonet, and what that does is increases the weight that the balloon has,' Wickersham explained.
What direction the wind blows in varies by altitude. So if Google wants to steer a balloon in another direction, it will have air blown in or out of the ballonet to change the balloon's weight, Wickersham said. Doing so will determine what altitude the balloon is flying at, and therefore the direction it floats in as well.
All of the electronics the balloons carry are put in a tiny basket. For example, there are solar panels to collect energy throughout the day, and a rechargeable battery on-board stores energy to use at night.
But most importantly, that basket contains specialised radios that capture LTE signals sent up from ground stations that are then beamed back down to the ground.
Hundreds of people can connect to the internet through one balloon because it beams internet that covers a roughly 25-mile in diameter on the ground. Antennas attached to buildings, like the one pictured above, can also capture the LTE signals.