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[–]FediNetizen[S] 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (5 children)

To explain for those that don't follow this stuff, for a few years now SpaceX has been working on building a giant constellation of several thousand satellites in LEO (Low Earth Orbit) to provide much faster and lower-latency (and hopefully lower cost) internet than is currently available.

The way legacy satellite services work is you have a few massive satellites parked in a geostationary orbit (about 36,000 km, or about 22,000 miles). This limits bandwidth, and also adds about a quarter of a second of round-trip latency because of how far the signal has to travel.

By having many satellites at very low (~1000 km) orbits that each only deal with a small area at a time, you have much more available bandwidth, and also you can achieve latencies pretty close to what you get with land service, or even faster for data that is being fetched from the other side of the world due to the speed advantage of light traveling in a vacuum vs light traveling in a fiber cable.

Now, it looks like Amazon is getting into this game. This is going to be great for the consumer because there will be more price competition.

Just to be clear, despite what some might claim, there are still bandwidth limitations, and this isn't going to be providing internet to everybody, mostly just the more rural areas where broadband internet options are limited or nonexistent.

[–][deleted] 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (4 children)

or even faster for data that is being fetched from the other side of the world due to the speed advantage of light traveling in a vacuum vs light traveling in a fiber cable.

The speed of light is the speed of light. There is no advantages in terms of that. In fact, there's a huge disadvantage with packet loss in satellites regardless of what you do, and the ongoing problems of so much as a bird in the sky knocking out your internet. Where I grew up, in the middle of nowhere, your only option was satellite internet. It's crap. Putting the satellites in low orbit would fix absolutely none of the reasons why it's crap.

Anyway the reason for the less latency is a shorter distance. Not any variation in the speed of light. If there's any advantage over direct fiber it would be only where a satellite might be able to have direct line of sight with a receiving station. Straight lines being a shorter distance possibly than a curve, or wherever the lines need to curve to. The DISADVANTAGES of course remain cloud cover, as well as the danger of radiation from the satellite sender/receiver you need to install.

[–]FediNetizen[S] 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (3 children)

The speed of light is the speed of light. There is no advantages in terms of that.

Anyway the reason for the less latency is a shorter distance. Not any variation in the speed of light.

Come on, man. Are you seriously not aware that the speed of light is dependent on the medium it's traveling through?

[–][deleted] 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (2 children)

Come on, man. Are you seriously not aware that the speed of light is dependent on the medium it's traveling through?

The differences between traveling in a cable, and traveling in air, are not important. In fact on the contrary the refractive index in the sky, especially on humid and cloudy days, is immensely greater obviously. The cable will almost certainly always be faster. What I was trying to explain is the reason for less latency between the satellites is the distance, not the medium change.

[–]FediNetizen[S] 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (1 child)

You can't beat the speed of light in a vacuum, and you're only passing through about a few 10s of km of atmosphere before you're basically in a vacuum. By contrast, in a fiber cable light is at about a constant ~0.7c. You've got a headstart because you don't need to bounce up to to the satellite first, but even if you had a single cable that circumnavigates the globe in a straight line, you'll still get there faster if your signal is traveling in space, purely because your light is going about 40% faster.

[–][deleted] 3 insightful - 1 fun3 insightful - 0 fun4 insightful - 1 fun -  (0 children)

Since you're not listening to me I'll just link other articles: https://www.zdnet.com/article/spacex-starlink-internet-prepares-for-beta-users/

The listed latency times for Starlink are greater on average than the listed latency range for fiber. As I said, the refractive index in the sky is going to be an issue. And, unlike fiber, cloud cover will completely disrupt service. (I consider Musk's version-2 claims to be pure marketing puff like he always does)