dissabte, 24 de febrer del 2018

How SpaceX plans to bring speedy broadband to the whole world

Musk has said the next generation SpaceX rockets could launch large satellites... or perhaps a number of small ones.
Musk has said next-generation SpaceX rockets could launch large satellites -- or perhaps a number of small ones.
After a third delay, Thursday is now the day SpaceX plans to launch two small prototype satellites aboard a Falcon 9 rocket, the beginning of what Elon Musk and his company hope will be a new way of connecting humanity. 
The launch was initially planned for Saturday, but was delayed twice to allow additional time for systems check and a third time due to high-altitude winds on Wednesday.
Also along for the ride into orbit is the larger Paz telecommunications satellite, but all eyes are on the smaller satellites, named Microsat-2a and Microsat-2b. 
The project has been relatively secret by SpaceX standards, but is currently known as Starlink and amounts to a new kind of satellite broadband internet service provider. Most other satellite internet services, like Viasat or HughesNet, rely on a handful of big satellites in geostationary orbit, over 22,000 miles (35,000 kilometers) above Earth.
Signals and data travel back and forth between those satellites and customers' satellite dishes, as well as larger ground stations on Earth, to bring the internet into the homes of hundreds of thousands of customers, often in rural locations with few other options. 
Traveling all those thousands of miles from high orbit can cause high levels of latency when using satellite internet, as anyone who's ever Skyped over such a connection will tell you. Things like real-time video calls and gaming can become difficult when there's lag and delay in the line from data having to travel to space and back over and over again. 
So the idea behind Starlink is to use satellites at a much lower orbit to cut down on all that lag time. Sounds great, but there's a catch. Because the satellites will be much closer to the surface of the Earth, they'll only be able to "see" far smaller areas, so a much greater number of them will be required to cover the whole planet.

starlink
SpaceX has declined requests to elaborate on the project, but Musk did acknowledge that the test satellites are aboard the Falcon 9 in for the first time in a tweet Wednesday morning. The company's application to the Federal Communications Commission outlines its plan to begin by deploying an army of 4,425 small satellites in low Earth orbit between 1,100 kilometers (684 miles) and 1,325 kilometers (823 miles) above us. 
Once the first 800 satellites in this constellation are up and running, that will be enough "to provide initial US and international coverage for broadband services," the company says in its FCC application. "Deployment of the remainder of that constellation will complete coverage and add capacity around the world."
But that's not all. Once its low Earth orbit constellation is up and working, SpaceX hopes to launch an even larger flock of satellites, 7,518 of them to be exact, at an orbit of around 340 kilometers (211 miles) in altitude.
SpaceX says this "VLEO constellation" would provide added capacity where it's needed around the world, "enabling the provision of high speed, high bandwidth, low latency broadband services that are truly competitive with terrestrial alternatives."
SpaceX isn't the only company hoping to operate a constellation of satellites in low Earth orbit. Globalstar and Iridium have operated dozens of satellites for voice services at that altitude for many years, and Starlink competitor OneWeb already has approval for a constellation of several hundred broadband satellites. But Musk's plan is arguably more ambitious by an order of magnitude. 
To make this audacious plan work, SpaceX has more emerging tech it will include on each satellite, in the form of lasers allowing them to communicate and coordinate with each other.   
The launch of the first two Starlink test satellites "fires the starting pistol on laser communications use in space to provide connectivity for even the most remote places on Earth," said Markus Knapek, an engineer and board member for laser communications company Mynaric. 
For their part, OneWeb and other competitors have filed their concerns with the FCC that SpaceX's massive Starlink constellations will endanger other satellites in orbit. SpaceX has responded that its plan meets all safety standards and allows for adequate buffers of space between other satellites.
Even still, over 10,000 satellites makes for an awful lot of space debris. 
SpaceX says in its application that it will deorbit satellites nearing the end of their useful lives, which it says should be roughly five to seven years. That means the satellites will be steered into Earth's atmosphere where they will burn up many years earlier than what's required by international standards.
Getting all those satellites up and flying doesn't happen overnight, however. SpaceX has so far just received FCC approval to launch the two test satellites. Its application for the larger Starlink project is still before the FCC, where Chairman Ajit Pai has given the plan his public endorsement. Even with a stamp of approval from the FCC, more approvals will be needed, including from the International Telecommunication Union. 
All this means you won't be jacking into SpaceX's network anytime soon. In fact, Musk says the full service probably won't be up and running until the middle of the next decade, just in time for it to help fund his other audacious plans, like sending us to Mars to give Starman a space high five.

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