Elon Musk, capitalizing on SpaceX’s unique ability to cheaply launch stuff into space, has announced that he’s working on deploying a constellation of some 700 satellites, for the purpose of bringing “very low cost” internet access to everyone on Earth. Satellite internet access could be very useful in rural parts of North America and Europe, but it’s the under-connected parts of the world (Asia, Africa, South America) that will be of more interest to Musk, both financially and ideologically.

A few days ago, the Wall Street Journal reported that Musk was working with WorldVu, a satellite internet startup that has slunk out of stealth over the last few months. WorldVu was set up by Greg Wyler, which previously founded O3b — a satellite internet company that is also meant to service the “other 3 billion” people who don’t have access to the internet. This morning, in a couple of tweets, Musk confirmed that SpaceX is indeed working on a “large formation” of satellites, with an official announcement to come in “2 to 3 months.” (He doesn’t confirm that SpaceX is working with WorldVu, but it seems highly likely.)

As far as I can tell, WorldVu is basically the same idea as O3b, but with a much larger constellation of smaller satellites that orbit at a lower altitude. The original WSJ report says that SpaceX/WorldVu wants to launch about 700 satellites, each weighing about 250 pounds (113 kg), into a fairly low-altitude orbit of 500-600 miles (800-965 km). 250 pounds is about half the weight of the smallest communication satellites currently in orbit — and yes, a constellation of 700 is about 10 times larger than Iridium’s constellation, which is currently the world’s largest.

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Other than the size of the constellation, we don’t have much in the way of technical details. We know that WorldVu acquired a Ku-band license from SkyBridge (a failed satellite internet company), and we know that the satellites will be placed in 20 different orbits to provide consistent coverage all over the world — but there’s no word on how fast the access will be, or how much it might cost. Musk tweeted that it would be “very low cost,” but might just be relative to existing satellite internet access (which tends to be very expensive).

Generally speaking, satellite internet access is a horrible experience: It’s expensive, slow, and unreliable. Because satellites are expensive to build and launch, companies usually try to cover a large area with just a few high-altitude satellites — but a higher orbit means higher latency and lower bandwidth. Low-altitude satellite internet can actually be very fast, with acceptable latency, but you need a lot of satellites to cover the same area. Historically, of course, launching 700 satellites — at perhaps $50 million each — would be completely untenable. Now, however, with SpaceX slashing the cost of getting into space, combined with smaller, cheaper satellites (reportedly just $1 million each), a massive constellation of low-altitude satellites doesn’t sound quite so silly. WorldVu should be using the lower-frequency (12-18GHz) Ku band, too, which is generally more reliable than 26-40GHz Ka band satellite communications (those high-frequency waves get attenuated by rain, cloud, atmosphere, etc.)

If SpaceX and WorldVu can pull this off — if Musk and Wyler can provide cheap, reliable internet access to the entire world — then this is a big deal. Satellites are by far the best way of providing internet access to rural areas, or countries that have large numbers of people who aren’t yet connected to the internet. At the last count, around 3 billion people had access to the internet, via a PC, smartphone, or other similar device — leaving four billion who aren’t connected, who are mostly located in China, India, and Africa, representing one of the biggest growth markets possible. If even a fraction of those sign up for some SpaceX/WorldVu internet access, you’d instantly have one of the world’s largest and richest ISPs.

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