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Re:The US military launched 500M needles into space (2019) by robonerd on Wednesday June 01, 2022 @01:40PM (#31585344)
WW3 will likely make a mess of orbit, particularly LEO. However most of the debris that intersects LEO will decay in the order of years to tens of years. After the war (assuming anybody is in any shape to be sending stuff to space in the first place) I think communication satellites in LEO will become the norm (moreso than it already is becoming.) This would be the obvious response to higher orbits being ruined by debris.

But such a war would be very bad in many ways, and if this happens I don't think worrying about space will be high on your list of personal priorities.

Re:The US military launched 500M needles into space (2019) by xwolfi on Wednesday June 01, 2022 @11:06PM (#31590847)
WWIII will not happen the way you think, it's already happening to some extent.

The difference with before is that the EU is largely pacified, the middle east only cares about Allah or not Allah, Russia cant invade its own backyard and is running out of teenagers to butcher.

This leaves the US, India and China as the trifecta of dangerous war machines. China I think will prefer to lead internal struggles against common cold variants to "win" victories and softly annoys the two others to keep them at bay - the party doesnt care about the country, only its own survival, India has only an interest in border conflicts with China and doesnt have the ability to succeed at any serious escalation of violence so will always avoid them, and stay unaligned with the US.

The US, you included as it s mostly americans proposing ideas of "world war" out of nostalgia for their golden past, has lost enough goodwill to be left alone before it can escalate, but is still trying hard to destabilize China - which means they care less about peace than removing the single party which annoys them to no end.

I dont think we'll fall in the american trap, but who knows, the military complex pressure is so high they have to fire all these guns at some points to build new ones. Hope they stay at invading poor countries all around that have no chance to defend themselves.

Re:The US military launched 500M needles into space (2019) by samstave on Wednesday June 01, 2022 @09:49PM (#31590388)
I would love to see the following... I think Ill try a short story about:

---

In preparation for a global war, a plan was put in place, in accordance with Continuity of Government ; Project Celestial Constellation.

A global network of subterranian launch facilities. Massive in scale. Their purpose: to re-spawn orbital assets as required to maintain Total Global Awareness in the event of Planetary Cataclysms.

There are four classifications of facility, each with a specific mission to re-establish, maintain and defend the Communications Constellation.

One facility is to clear orbital debris. One is to launch replacement communication constellations. and one serves to defend against orbital attacks against these assets.

The worst part.... the rebels are attacking the re-spawns as they launch. We have lost nearly 100 this year alone...

Re:The US military launched 500M needles into space (2019) by idealmedtech on Wednesday June 01, 2022 @02:49PM (#31586357)
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.
Re:The US military launched 500M needles into space (2019) by robonerd on Wednesday June 01, 2022 @03:11PM (#31586590)
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.

Re:The US military launched 500M needles into space (2019) by jltsiren on Wednesday June 01, 2022 @03:42PM (#31586957)
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.
Re:The US military launched 500M needles into space (2019) by kevin_thibedeau on Wednesday June 01, 2022 @06:15PM (#31588836)
A satellite killer would need the ability to rendezvous with a target. You're not getting that level of capability for the same price as a box with a radio.
Re:The US military launched 500M needles into space (2019) by swayvil on Wednesday June 01, 2022 @07:20PM (#31589388)
You only need to throw a cloud of junk into its orbit. Seems like a big easy target.
Re:The US military launched 500M needles into space (2019) by wumpus on Wednesday June 01, 2022 @08:03PM (#31589718)
Actual systems usually hit the target with a single projectile, not a cloud of junk.
Re:The US military launched 500M needles into space (2019) by mlyle on Wednesday June 01, 2022 @08:23PM (#31589855)
Sure. The author is positing a dumb "shotgun" system for blanket space denial instead of a system intended to kill a single satellite. Just putting a lot of crap in LEO is good enough for denial. Dumb boxes that can maneuver and choose when to become a pile of crap are even better.
Re:The US military launched 500M needles into space (2019) by JumpCrisscross on Wednesday June 01, 2022 @09:12PM (#31590170)
> author is positing a dumb "shotgun" system for blanket space denial instead of a system intended to kill a single satellite

Fighter jets use missiles, not flak. Above certain velocities and a certain degree of freedom in the third dimension, shotguns disperse uselessly more than hit anything. At the point you're getting close enough to make a hit probable you're already most of the way towards a direct strike anyway.

Re:The US military launched 500M needles into space (2019) by mlyle on Wednesday June 01, 2022 @09:22PM (#31590225)
> Fighter jets use missiles, not flak.

Do you think the missiles go and touch the opposing fighter jet? Hit-to-kill systems exist, but most missiles maneuver, get as much of an intersecting path as they can, and then explode to kill the target with fragments.

> At the point you're getting close enough to make a hit probable you're already most of the way towards a direct strike anyway.

Here, you don't select for the highest probability of kill on a certain pass, but instead the highest probability of damage integrated over many orbits. You also don't select for the highest probability of killing a given SV, but of killing satellites in a given constellation with closely related orbits.

Re:The US military launched 500M needles into space (2019) by JumpCrisscross on Wednesday June 01, 2022 @09:29PM (#31590275)
> maneuver, get as much of an intersecting path as they can, and then explode.

Which is the "getting close enough to make a hit probable" I described.

> don't select for the highest probability of killing a given SV, but of killing satellites in a given constellation with closely related orbits

I get the hypothesis. But if you run the orbital math, interaction is vanishingly unlikely. Kessler syndrome is triggered by massive orbital objects breaking up and creating a domino effect at high altitudes, where orbital decay is minimal on human timeframes. Kessler concerns were raised with respect to Starlink, but I haven't seen anyone balance the math for massive numbers of small objects. Even for the classic case, when you actually run simulations, most objects don't interact.

Re:The US military launched 500M needles into space (2019) by mlyle on Wednesday June 01, 2022 @10:50PM (#31590733)
> But if you run the orbital math, interaction is vanishingly unlikely.

E.g. a Falcon 9 can put 14 tonnes into a higher LEO. Assume you fill it 90% with 1cm diameter tungsten spheres, and the rest with an optimized dispersal system. That's 1.26 million spheres slowly decaying through your target orbit, and you can end up with a favorable initial phase, altitude, and inclination.

You'd be tripling the amount of debris of that scale in orbit in one launch, in a way that's disproportionately targeted at a specific constellation.

(Probably 1cm diam is still excessively large. Also, when we talk about the original idea, you could have many smaller, even more optimized shots at individual spacecraft in the constellation).

Re:The US military launched 500M needles into space (2019) by JumpCrisscross on Wednesday June 01, 2022 @11:48PM (#31591104)
> 1.26 million spheres slowly decaying through your target orbit, and you can end up with a favorable initial phase, altitude, and inclination

Three degrees of freedom are deceiving. Millions of projectiles sounds like a lot. It’s not.

You could do this hundreds of thousands of times in LEO and thousands in MEO and still barely change a single satellite’s collision odds.

Re:The US military launched 500M needles into space (2019) by mlyle on Thursday June 02, 2022 @12:01AM (#31591183)
Satellites die from collisions today.

> You could do this hundreds of thousands of times in LEO and thousands in MEO and still barely change a single satellite’s collision odds.

I have to think that multiplying the number of debris objects by 300,000 for a few months *, and preferentially targeting that debris at a specific satellite would change its odds a bit. So, you're way off in hyperbole-land at this point.

Of course, it all depends on what we mean by "targeting". Still, one launch gets you approximately 3x the total amount of debris in orbit, and the opportunity to choose how it's distributed.

* Objects with a mass/surface area ratio of ~15 kg/m^2 decay in about a year in LEO, depending upon space weather and other factors. The tungsten balls have a ratio of 32 kg/m^2, so can be expected to last a fair bit longer.

Re:The US military launched 500M needles into space (2019) by Teever on Thursday June 02, 2022 @03:43AM (#31592454)
Something doesn't jive here.

If a million projectiles in one orbit isnt something to worry about then why are we worried about Kessler Syndrome with the thousands of satellites and junk that is already up there?

Re:The US military launched 500M needles into space (2019) by JumpCrisscross on Thursday June 02, 2022 @07:42AM (#31593685)
> why are we worried about Kessler Syndrome with the thousands of satellites and junk that is already up there?

One, Kessler syndrome should really be called the Kessler hypothesis since we’ve never actually proven it’s a problem in any real form. To the degree it’s been rigorously modelled, it would create a lot of property destruction in a limited number of orbital planes, not block access to space. The problem is breaking stuff. Not blocking. Two, where it’s been rigorously modelled and shown to be a problem (again, only for a limited set of planes) it derives from something big breaking apart. Not lots of small stuff. And again, we’re talking about a bunch of property destruction. Not annihilation of everything in the plane let alone orbit.

Re:The US military launched 500M needles into space (2019) by mlyle on Friday June 03, 2022 @12:55AM (#31604451)
First, no one's really talking about Kessler syndrome and cascades except you, though they make any denial effects bigger.

Second, take the volume of the entire shell around earth from 400km to 450km up-- that's about 3 * 10^19 cubic meters. 1.3 million objects scattered randomly over this entire volume yields a density of 4 * 10^-14 / m^3, which sounds like a small amount, until you consider that a moderate sized object orbiting at that altitude might sweep 20000 m^3/second. You'd expect this indiscriminate attack on LEO from a single launch to hit 2.5% of objects with this 2.5 m^2 cross-section in the year that the BBs stayed in orbit. You'd expect to hit the ISS about once every 2 hours and to accrue hundreds or thousands of hits.

To the extent that you focused your attack on certain planes and on a narrower range of altitudes, you could expect it to be more effective. And, of course, to the extent that there's any further fragments created / Kessler-type effects, you can expect more effect.

Re:The US military launched 500M needles into space (2019) by GekkePrutser on Wednesday June 01, 2022 @08:52PM (#31590038)
But this kind of denial works the same for all parties' sats. Kind of a mutually assured destruction.

I'm sure targeted options will be favoured by most parties.

Re:The US military launched 500M needles into space (2019) by mlyle on Wednesday June 01, 2022 @09:02PM (#31590113)
> But this kind of denial works the same for all parties' sats. Kind of a mutually assured destruction.

Yah. Slightly favors your own satellites in the odds, but not wonderfully so.

At the same time, if you're facing an adversary which depends upon LEO much, much more... this might be an attractive strategy.

Re:The US military launched 500M needles into space (2019) by bee_rider on Wednesday June 01, 2022 @03:57PM (#31587179)
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.

Re:The US military launched 500M needles into space (2019) by robonerd on Wednesday June 01, 2022 @04:12PM (#31587383)
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.

Re:The US military launched 500M needles into space (2019) by jltsiren on Wednesday June 01, 2022 @05:15PM (#31588232)
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.

Re:The US military launched 500M needles into space (2019) by robonerd on Wednesday June 01, 2022 @06:30PM (#31588973)
> Boost-phase interceptors would be big expensive weapons systems

Not very big actually, not if the interceptors are placed in LEO. They're a hell of a lot smaller and cheaper than the missiles they're meant to intercept. The kill vehicles themselves are only a few kilograms, very small and light weight. For such light-weight interceptors positioned in LEO, you don't need much booster to get the job done. You can get away with a booster much smaller than an SM-3.

> 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

The more you have, the less delta-v they need. That's why Brilliant Pebbles proposed thousands if not tens of thousands of them. Launching such a huge number of interceptors would be possible with Falcon 9, but Starship would be much better at it.

> Maybe China decides to take Taiwan

Maybe they would, but they would have to be insane to start a symmetric war with America itself. And that's the whole point.

> Deploying such large-scale missile defense systems would be obvious to everyone.

If you've been paying attention, you'll have noticed that China and Russia haven't been very secret about their interest in countering Starlink. It's not because they're afraid the US might give uncensorable internet to Chinese and Russian people, as I've seen some on HN speculate. They obviously perceive the strategic threat already. Besides starting the war first, there's not a whole lot they can do about it. If they start the war first, start it now, they'll probably kill a lot more Americans than if they wait and do it later. But that doesn't matter because they'd still all die, so they aren't going to do it. Neither China nor Russia has a BMD system that could prevent America from killing them all.

Re:The US military launched 500M needles into space (2019) by cinquemb on Wednesday June 01, 2022 @07:52PM (#31589615)
I think as far as operational capabilities go, all BPI stuff is just not there (at least from public info) and at best, starlink would only be good a large scale detection, target aquisition and tracking:

[0]"While boost-phase defense has been advocated as the most efficient way to deal with fractionated payloads and exoatmospheric (midcourse) penetration aids, it is extremely sensitive to assumptions about threat booster characteristics. Over time, boost-phase defense tends to be renamed ascent-phase defense when the kinematic realities set in. In fact, ascent-phase defense is code for engagement in the postboost or early midcourse phases of flight.

The limitations and complications of a surface-based boost-phase defense lie primarily in the concepts of operations (CONOPS), policy, time, and geography. Since the timelines for engagement in the boost-phase are extremely short, the on-site commander must have authorization from the National Command Authority to launch an interceptor immediately after a threat missile has been detected.1 Also, access must be gained to countries adjacent to the threat country in order to position a boost-phase system close enough, and at the correct geometries, to successfully engage the threat missile. Finally, boost-phase systems are only effective against countries that do not have large enough landmasses to allow them to launch missiles from deep within their territory.

The airborne laser is designed to deliver energy at the speed of light to perform the boost-phase intercept mission. Space-based lasers were also pursued in the past. Virtually no fly-out time is involved, and the beam agility is a function only of how fast the pointing optics can be repositioned. While laser weapons sound like the obvious answer, the energy that a laser can deliver on a target is limited by the power available and the aperture of the device. Atmospheric effects disturb the beam. Much has been accomplished in advancing the pointing and tracking capabilities and the adaptive optics to maintain beam quality, but some fundamental limitations remain."

[0] https://nap.nationalacademies.org/read/13189/chapter/4

Re:The US military launched 500M needles into space (2019) by robonerd on Wednesday June 01, 2022 @10:37PM (#31590636)
The part of this document that you're quoting is talking about the limitations of land/sea based boost-phase interceptors. Scroll down to the Space-Based Interceptors section. I don't think there's much substance here.. It talks about kill vehicle size (see: LEAP), and mentions that coverage depends on the number of interceptors and the inclination of their orbits (no kidding.)
Re:The US military launched 500M needles into space (2019) by cinquemb on Thursday June 02, 2022 @12:17AM (#31591288)
The section i quote referrers to space based lasers too. I also haven't see anywhere publicly on any actual space based kinetic system even in testing for BPI usuage (which would still face the same kinematic issues with land and sea based system).
Re:The US military launched 500M needles into space (2019) by WalterBright on Wednesday June 01, 2022 @09:05PM (#31590126)
I read in the Scientific American that a defense against lasers would be simply spinning the target, which would require the attack laser to have much more power. The target can be made shiny, and can be coated with an ablative material.
Re:The US military launched 500M needles into space (2019) by cinquemb on Thursday June 02, 2022 @12:48AM (#31591444)
Yeah, I'd factor that into major limitations with the space based laser systems. Only think I can think of that could work around that is if one used an array of lasers that could constructively interfere during boost phase that could cause some kind of major turbulence at the point of intersection (maybe along the lines of the laser collisions here[0]:

"Fülöp and colleagues argue that the energy problem could be overcome by splitting the laser pulse into two equal-energy pulses, which then hit the target simultaneously at different, precisely calculated angles of incidence (see figure). Through simulations, the team showed that when the laser pulses collide, a standing wave forms inside the solid target that increases the peak electric field. With the same pulse intensity used in previous experiments, their calculations suggest that the technique can double the energy of the proton beam and produce five times as many protons — all with far more flexible control parameters than required before.").

[0] https://physicsworld.com/a/laser-collisions-could-boost-prot...

Re:The US military launched 500M needles into space (2019) by wumpus on Wednesday June 01, 2022 @08:05PM (#31589728)
You mean the completely failed Brilliant Pebbles concept?

https://en.wikipedia.org/wiki/Brilliant_Pebbles

Re:The US military launched 500M needles into space (2019) by robonerd on Wednesday June 01, 2022 @10:13PM (#31590505)
"Completely failed" as in nobody could possibly launch a constellation that large in the 80s and 90s, yes. The economics of massive constellations have changed, one already has thousands of satellites in orbit.

Look up SDA and the National Defense Space Architecture. They're talking about thousands of satellites in LEO. They call it pLEO (proliferated LEO.)

Re:The US military launched 500M needles into space (2019) by wumpus on Thursday June 02, 2022 @12:15AM (#31591276)
I've been watching SDA from the start as it's possible it will give us a high bandwidth connection to the South Pole Telescope. Meaning we don't have to wait for summer to fly the data from the EHT annual observation to civilization.

As for Brilliant Pebbles, that's one reason it's a total failure, but not the only one.

Re:The US military launched 500M needles into space (2019) by Teever on Thursday June 02, 2022 @03:49AM (#31592487)
would you care to share the other reasons thst you feel Brilliant Pebbles is a total failure?
Re:The US military launched 500M needles into space (2019) by cm2012 on Wednesday June 01, 2022 @03:57PM (#31587180)
I don't know, destruction is almost always easier than construction. And China demonstrated an anti-satellite laser already.
Re:The US military launched 500M needles into space (2019) by wumpus on Thursday June 02, 2022 @12:17AM (#31591287)
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.

Re:The US military launched 500M needles into space (2019) by georgeg23 on Thursday June 02, 2022 @02:24AM (#31592014)
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-...

[2] https://en.wikipedia.org/wiki/Starlink#Military_satellites

[3] https://en.wikipedia.org/wiki/Michael_D._Griffin#Career

Re:The US military launched 500M needles into space (2019) by bluGill on Wednesday June 01, 2022 @03:33PM (#31586849)
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)