7 ms·

LEO is too susceptible to interference (of the physical, not radio, kind) for any serious digital communications infrastructure to be placed there. I could see

LEO is too susceptible to interference (of the physical, not radio, kind) for any serious digital communications infrastructure to be placed there. I could see laser-based swarms of comms satellites being used (cubesat size, not starlink size), but I don't think the economics are there quite yet.

robonerd 4y ago
It's not clear what exactly you mean by physical interference, but either way I think you're mistaken. Starlink is already proving the viability of launching huge constellations of fairly large (a ton or so) LEO satellites. If you're talking about debris grounding these constellations, that's a problem that resolves itself given enough time, as that debris deorbits naturally. If you're talking about intentional physical interference, aka anti-satellite weapons, the solution to that is having the ability to rapidly replenish the constellation (SpaceX is good at this, and with Starship they'll be even better at it; hundreds of replacement satellites with a single launch.) In the event of a war, a constellation could be kept operational through the brute force of launching more satellites faster than they're destroyed. Of course this will make a huge mess, but that's what wars do. Anyway, they're going forward with this already. The National Defense Space Architecture calls for a very large constellation of LEO communication satellites forming a mesh network using inter-satellite laser links. Starlink is likely dual-use technology and has been intended as such from the start.
- jltsiren 4y ago
  If you can launch hundreds of useful satellites with a single launch, you can also launch thousands of satellite killers for the same price. A simple short-lived satellite with some sensors, minor maneuvering capabilities, and the ability to turn into a debris cloud on a close pass should be quite effective when deployed in huge numbers. The economies of scale favor destruction if you really don't care about the consequences.
  - bee_rider 4y ago
    I think things like orbital decay and coverage per satellite are the more serious concerns. I mean, LEO is still harder to reach out to than almost anywhere on Earth. The main deterrent to attacking our assets in LEO or on Earth is that such an act would at least have some serious political fallout, and potentially start a war depending on how annoying it is.
  - robonerd 4y ago
    Having thousands of boost-phase interceptors already in LEO actually puts a real damper on anybody trying to do something about it, the economics of the game favor whoever implements such a system first. They will be able to use large rockets to efficiently launch huge numbers of satellites, while the boost-phase interceptors in LEO (constantly replenished via that capability) prevent the enemy from doing the same. Big picture, even if Russia and/or China managed to turn LEO into an impenetrable barrier of debris before the war was lost for them anyway, what would they actually have accomplished? The satellites that previously acted as America's shield would now be debris that would continue to shield America, and America would still have Aegis BMD around the world. Symmetrical war with America is beyond stupid, there is no balance, no fair fight. The purpose of these systems is to ensure that it stays this way, so that nobody tries in the first place.
    - jltsiren 4y ago
      Boost-phase interceptors would be big expensive weapons systems. Because they have only a few minutes to hit before the target deploys the payload, they would have to expend lots of delta-v to guarantee intercept. Deploying such large-scale missile defense systems would be obvious to everyone. By the usual cold war calculus, such attempts would likely trigger a nuclear war. If you attempt to neutralize enemy nuclear deterrent, you are announcing your first strike intentions to everyone. As for why, maybe the reason wouldn't even involve America that much. Maybe China decides to take Taiwan, and to prevent America from interfering, they choose to destroy LEO for everyone. Maybe it would be an acceptable sacrifice for them, as they are more interested in controlling their neighborhood than projecting power to faraway places.
- cm2012 4y ago
  I don't know, destruction is almost always easier than construction. And China demonstrated an anti-satellite laser already.
- wumpus 4y ago
  Starlink 1 is 150kg, Starlink 1.5 is thought to be ~ 220kg. Starlink 2 appears to be more than a metric ton, but none have been launched.
- georgeg23 4y ago
  The Biden administration appears to have put the full blown militarization of space on ice for now (at least delaying the Mike Pompeo calls the "Strategic Defense Initiative of our time, the SDI 2.0"[1]), but there are still a number of demonstrations[2] going forward with Starlink funded by the Space Development Agency started by Elon's pal Michael D. Griffin[3]. This has been pretty hush hush, but voters should know what they're getting in the midterms if they support this. In my opinion it will indeed lead to WWIII. I think Elon knows that but justifies it by thinking he needs the military industrial complex funding for Mars. [1] https://www.hudson.org/research/17482-nuclear-weapons-china-and-a-strategic-defense-initiative-for-this-century https://www.hudson.org/research/17482-nuclear-weapons-china-... [2] https://en.wikipedia.org/wiki/Starlink#Military_satellites https://en.wikipedia.org/wiki/Starlink#Military_satellites [3] https://en.wikipedia.org/wiki/Michael_D._Griffin#Career https://en.wikipedia.org/wiki/Michael_D._Griffin#Career
bluGill 4y ago
LEO has low latency though, which is important. Communications via satellite in higher orbits suck. Ever dealt with 600ms ping times? I have, you get used to it, but I'm glad to be on ground based internet now, things just feel faster. (and the web is still slow)

robonerd 4y ago

It's not clear what exactly you mean by physical interference, but either way I think you're mistaken. Starlink is already proving the viability of launching huge constellations of fairly large (a ton or so) LEO satellites. If you're talking about debris grounding these constellations, that's a problem that resolves itself given enough time, as that debris deorbits naturally. If you're talking about intentional physical interference, aka anti-satellite weapons, the solution to that is having the ability to rapidly replenish the constellation (SpaceX is good at this, and with Starship they'll be even better at it; hundreds of replacement satellites with a single launch.) In the event of a war, a constellation could be kept operational through the brute force of launching more satellites faster than they're destroyed. Of course this will make a huge mess, but that's what wars do. Anyway, they're going forward with this already. The National Defense Space Architecture calls for a very large constellation of LEO communication satellites forming a mesh network using inter-satellite laser links. Starlink is likely dual-use technology and has been intended as such from the start.

jltsiren 4y ago
If you can launch hundreds of useful satellites with a single launch, you can also launch thousands of satellite killers for the same price. A simple short-lived satellite with some sensors, minor maneuvering capabilities, and the ability to turn into a debris cloud on a close pass should be quite effective when deployed in huge numbers. The economies of scale favor destruction if you really don't care about the consequences.
- bee_rider 4y ago
  I think things like orbital decay and coverage per satellite are the more serious concerns. I mean, LEO is still harder to reach out to than almost anywhere on Earth. The main deterrent to attacking our assets in LEO or on Earth is that such an act would at least have some serious political fallout, and potentially start a war depending on how annoying it is.
- robonerd 4y ago
  Having thousands of boost-phase interceptors already in LEO actually puts a real damper on anybody trying to do something about it, the economics of the game favor whoever implements such a system first. They will be able to use large rockets to efficiently launch huge numbers of satellites, while the boost-phase interceptors in LEO (constantly replenished via that capability) prevent the enemy from doing the same. Big picture, even if Russia and/or China managed to turn LEO into an impenetrable barrier of debris before the war was lost for them anyway, what would they actually have accomplished? The satellites that previously acted as America's shield would now be debris that would continue to shield America, and America would still have Aegis BMD around the world. Symmetrical war with America is beyond stupid, there is no balance, no fair fight. The purpose of these systems is to ensure that it stays this way, so that nobody tries in the first place.
  - jltsiren 4y ago
    Boost-phase interceptors would be big expensive weapons systems. Because they have only a few minutes to hit before the target deploys the payload, they would have to expend lots of delta-v to guarantee intercept. Deploying such large-scale missile defense systems would be obvious to everyone. By the usual cold war calculus, such attempts would likely trigger a nuclear war. If you attempt to neutralize enemy nuclear deterrent, you are announcing your first strike intentions to everyone. As for why, maybe the reason wouldn't even involve America that much. Maybe China decides to take Taiwan, and to prevent America from interfering, they choose to destroy LEO for everyone. Maybe it would be an acceptable sacrifice for them, as they are more interested in controlling their neighborhood than projecting power to faraway places.
cm2012 4y ago
I don't know, destruction is almost always easier than construction. And China demonstrated an anti-satellite laser already.
wumpus 4y ago
Starlink 1 is 150kg, Starlink 1.5 is thought to be ~ 220kg. Starlink 2 appears to be more than a metric ton, but none have been launched.
georgeg23 4y ago
The Biden administration appears to have put the full blown militarization of space on ice for now (at least delaying the Mike Pompeo calls the "Strategic Defense Initiative of our time, the SDI 2.0"[1]), but there are still a number of demonstrations[2] going forward with Starlink funded by the Space Development Agency started by Elon's pal Michael D. Griffin[3]. This has been pretty hush hush, but voters should know what they're getting in the midterms if they support this. In my opinion it will indeed lead to WWIII. I think Elon knows that but justifies it by thinking he needs the military industrial complex funding for Mars. [1] https://www.hudson.org/research/17482-nuclear-weapons-china-and-a-strategic-defense-initiative-for-this-century https://www.hudson.org/research/17482-nuclear-weapons-china-... [2] https://en.wikipedia.org/wiki/Starlink#Military_satellites https://en.wikipedia.org/wiki/Starlink#Military_satellites [3] https://en.wikipedia.org/wiki/Michael_D._Griffin#Career https://en.wikipedia.org/wiki/Michael_D._Griffin#Career

bluGill 4y ago

LEO has low latency though, which is important. Communications via satellite in higher orbits suck. Ever dealt with 600ms ping times? I have, you get used to it, but I'm glad to be on ground based internet now, things just feel faster. (and the web is still slow)