Google's Project Loon flies its Internet-broadcasting balloons above 99 percent of the Earth's atmosphere. They're nearly in outer space. But how does Google steer them without popping, a problem that afflicts weather balloons at that altitude?
The answer, it turns out, is all in the data. Keith Bonawitz, computational choreographer for the Google [x] Lab, took to YouTube to explain how the balloons survive at extremely high altitudes, which has never been done before -- at least, not on such a large scale.
"We'll have a fleet of balloons in air all the time," Bonawitz said, which will be tracked with GPS. Right now, though, it's only a relative few test balloons.
The problem for Google is that weather balloons, which are one of the few comparable existing forms of technology to Project Loon, rise until they eventually pop.
"The amount of time [the weather balloon] spends in the stratosphere is pretty limited," he said. So Google has been learning wind patterns from the balloons and sharing the data with the National Oceanographic and Atmospheric Administration.
Analyzing the stream of data from Loon's balloons has been the key to keeping the balloons afloat. The balloons are actually flying at the same speed as the wind currents themselves.
"We've flown microphones on our balloons, and it's very quiet when we're flying in the stratosphere. That's because there's no wind rushing past, and that's because we're flying at the same speed as the wind around us." Further analyzing the GPS-provided data, he said, lets Google steer the balloons and keep them functioning long past when normal weather balloons would have popped.
Google has partnered with NOAA to share "some of the data" from their balloons into NOAA's wind models. The end goal? NOAA will help Google keep its fleet airborne, and Google will help NOAA make better wind predictions for others.
"We have this ever-improving understanding of the stratosphere," said Bonawitz.