We’ll have a brief article at Starlink: Thenon geosynchronous communication system by SpaceX. I’ll try to illustrate how it will change the future and show that it’s not as ludicrous as it seems. Let’s dive into it! There are roughly 500 of these currently in orbit and most of you will know them from satellite television. Yep, that’s where you point your dishes. The ISS orbits much more closely at 400 km, in fact, it’s so close you wouldn’t even notice it’s in space at all from up here.
Red Dot Zips:
The red dot zips across the sky at 8 km/sin order to not fall back to the ground. It counters gravity with its own inertia like a giant centrifuge. The Starlink constellation will have a very similar orbit but there will be many many more. This is no coincidence because SpaceX will launch from the same launch site in Florida and that’s the highest inclination they can still reach somewhat efficiently. The first batch you can see here consists of almost 1600 satellites distributed over 24 orbital planes with 66 satellites each not counting on-orbit spares.
These spare satellites are basically a buffer to make sure a failing satellite can be replaced quickly. This first constellation will operate from an altitude of 550 km and will be able to communicate with itself and the ground using microwaves similar to your smartphones. But don’t get too excited about that. 550 km is not in breach of any regular smartphones you will not be able to browse the web like that, at least not in a regular fashion but we’ll discuss that later. The plan is to use dishes on terminals that can track the satellites by simply following them.
This will change and modernize overtime as SpaceX usually does. They will iterate on the design of these satellites and terminals starting with the most basic of hardware evolving them into whatever proves the best over time. They have actually launched two test articles to space already as a secondary payload. Tintin A and B named after the Belgian comic character Tintin or “TinTin” (french pronunciation). They work for in the order of 15 minutes days they fly by the US with high bandwidth and 25 ms of latency. Speaking of latency,
This used to be the issue with satellite communication as it was for the most part using those geosynchronous orbits far out. The speed of light is 300.000 km/s so in order for a signal to bounce back and forth twice for the ping-pong or ping test, it would travel at least 140.000 km or roughly half a second. That’s a big delay which is fine for one-directional streaming but incredibly painful for anything else, especially online gaming. But wait second one-directional streaming? Yep, I would argue what many don’t count with when it comes to Skylink is streaming.
You could in theory use regular cellular internet to ask for data and then use Starnet to provide it in even the most remote of areas directly onto a mobile device. However, that’s just my speculation and it really depends on whether the signal strength is strong enough to be picked up with an antenna that fits inside a smartphone. But I can imagine companies could sell pocket dishes with receivers only which don’t require special radio licenses. Anyhow, important to note is SpaceX could bring satellite television to smartphones no matter where you are.
I used to think Starlink was completely supplementary to the existing market as ground-based 5G systems will offer higher speeds and a quickerlatency, but as it turns out they could really threaten those valuable satellite television companies that ironically fund SpaceX today by launching satellites with them. But that of course depends on whether SpaceX will make use of it or not. In the end, there is enough streaming you can do online which will probably exploit most of the bandwidth already.
What SpaceX could also do is to mount GPS transmitters to offer positioning services. Thinking about it again that could turn into a problem though since no government had direct control over it so bad actors could abuse it to guide missiles. Regular GPS can be turned on and off or even manipulated to send missiles back to where they were coming from. The whole globe is tracked via infrared sensors from space so any device that exhausts a lot of heat is immediately picked up by the military which is vital not only to defend against attacks.
Also to prevent people from even attempting it. I guess SpaceX won’t offer to position services at least without governmental control over it or only with very low precision to tellin which country you are but not on which grassholm your sitting. So what remains is the internet which is, of course, the most important communication infrastructure nowadays. It will as mentioned offer high bandwidth in the gigabit range per user but with a comparatively okay latency of roundabout 10 ms to local servers or and this is the main advantage 30 to 60 ms all across the globe.
Yep, it will even beat a direct optical fiber connection because signals in these fibers travel at only 60-70% of the speed of light. The longer the distance the higher the advantage of such a space-based system. 30 – 60 ms is not great for online shooters but totally fine for most other games and of course calls. But I didn’t come up with that one by myself. There is a great article by I think a professor called Mark Handley. He wrote software to simulate the constellation’slinks and latency of the system pretty much proving the point.
I have never really thought about satellites being faster than a direct optical fiber link across the ocean. And this initial constellation will as mentioned only be the first and there are many more to come. The final low earth constellation will consist of almost 5000 satellites on different orbits and this is still not all. This will more than double in the long run as SpaceX will try to utilize a very low earth orbits below 350 km and therefore below theISS.
This one is further out and will probably not fund BFR like the rest. Yep, this whole constellation is supposed to fund SpaceX’s next-gen rocket so it is not a 20-year plan but supposed to be finished in just a few years from now. How can they do it you may ask? This more than doubles all satellites that are in space today. And won’t it cause crashes and debris? Yep, it is not an easy task but each teal sphere you can see here has actually a purpose. It is 60 km wide and that is exactly the safe zone around a satellite SpaceX will keep free.
Given a perfectly optimized constellation, which mine isn’t, none of these spheres should ever intersect with another. That is a lot of safe zones even if one satellite should fail. It would take many months to drift 60 km off course in which SpaceX could in theory rendezvous with some kind of on-orbit garbage collector that deorbit uncontrolled satellites. What sets SpaceX apart from others is they are at the source or they are the source for that matter. Unlike other companies that try to do the same, they can use free rockets.
Yes, their used boosters are already paid for so they can start out by simply using and reusing those without having to buy new ones. This is an incredible advantage over any competitor which won’t be able to operate a similar fleet at a competitive price point. Maybe amazon with their New Glenn rocket but that’s another article. Now, of course, satellites won’t only fail by accident. If you do the math 5000 satellites with a lifespan of 5 years each means 20 satellites failing per week on average.
They will not only have to deorbit them on their own but will also need an insane launch rate to maintain the whole fleet and they can’t yet reuse their upper stage. Building so many upper stages and satellites will make funding BFR a real challenge. So, and this is just my conclusion, they have to reuse their upper stage for Skynet, I mean Starlink. They can’t wait for BFR because this is meant to fund it and they can hardly fund it by building so many satellites and upper stages. Of course, Elon Musk himself tweeted it out recently.
Now let’s assume they really do it and manage to reuse it. What’s with all the debris falling to the ground? 20 satellites burning up a weak or a 1000per year is insane. According to their simulations, there is a high chance of a couple of kgs of metal surviving reentry, and these pieces will re-enter and crash into the ground somewhere. Of course, most will do so into the ocean but some will inevitably crash into the ground. They could harm people and cause fires.
That’s quite a long-term risk to take soI personally believe SpaceX will at least in the long run, as their technology evolves, have to come up with something new – again. Reusable satellites! Yep, mounting a small heatshield, maybe protective housing and parachute is all it takes. Mini Dragons so to speak. I’m actually pretty sure they will do it. Refueling satellites on orbit would be probably too complex as there are so many in different planes and they also can’t really upgrade them like that.