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.
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.
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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...
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.
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.
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.
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.
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).
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.
> 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.
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?
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.
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.
I'm sure targeted options will be favoured by most parties.
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.
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.
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.
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.
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.
[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."
"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...
Look up SDA and the National Defense Space Architecture. They're talking about thousands of satellites in LEO. They call it pLEO (proliferated LEO.)
As for Brilliant Pebbles, that's one reason it's a total failure, but not the only one.
Starlink 2 appears to be more than a metric ton, but none have been launched.
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
It would likely also mean nuclear winter and many other bad things, but permanently denying use of satellites is likely the first global cost of WW3.
As for "permanently denying use of satellites", this is only partially true. High orbits would be fucked for millennia, but LEO would mostly clear up before the century is out. I know that seems 'forever', but it isn't. Also, depending on the severity of the debris, interplanetary exploration would not necessarily be out of the picture; if the debris is severe enough that a GSO satellite has a 99% chance of being destroyed within a year, then that orbit is as good as ruined. But if you only plan to pass through that region for a few hours, not spend a whole year there, you might be able to do that if you can tolerate some risk. It'd be like running across a highway, except the cars move faster than bullets and won't brake for you. If you hang out in the middle of the road you are certain to get hit. If you time it right and run across, you have a chance of getting through.
> "Going back to the needles, in case you’re wondering, despite the planned obsolescence, as of 2019, a few dozen clumps of them remain in orbit and are closely tracked..."
"On 11 January 2007, China conducted an anti-satellite missile test in which one of their FY-1C weather satellites was chosen as the target. The collision occurred at an altitude of 865 kilometres, when the satellite with a mass of 750 kilograms was struck in a head-on-collision by a kinetic payload traveling with a speed of 8 km/s (18,000 mph) in the opposite direction. The resulting debris orbits the Earth with a mean altitude above 850 kilometres, and will likely remain in orbit for decades or centuries.[18]" (https://en.wikipedia.org/wiki/Kessler_syndrome#Anti-satellit...)
Kessler syndrome requires the rate of debris creation be greater than the rate of clearing and the rate of clearing in higher orbits is very slow.
https://amostech.com/TechnicalPapers/2012/Orbital_Debris/NIK...
How much debris though? If I put orange juice in my coffee mug, after a few runs through the dishwasher there may technically be a few particles of orange juice left, but my taste buds probably won't collide with it.
To attempt extend your analogy: you might be confident that most of the juice was washed out of the mug after a few cycles set to scour, but if you are deathly allergic to any exposure to oranges, what's your risk tolerance?
Make sure you clean the dishwasher trap, as well. :)
That's the key question the whole matter hangs on, but there's no objective answer for it. Neil Armstrong privately estimated his chance for successfully returning to earth at 90%. That's alarmingly low! That's barely safer than Russian roulette.
Determining how much risk can be tolerated means figuring out how badly you want the thing. The more you want something, the more risk you can tolerate. Satellites are extremely important to our society, so governments would continue launching the satellites they value most, even if the expected lifespan of the satellite due to space debris was very short.
Of course, superfluous and casual use of space would grind to a halt. One of many casualties of war.
A head on collision would be incredibly violent and would disperse a large cloud of debris over a large area - some of that would fall back to earth quickly. This would be incredibly unlikely, given that most objects above Earth orbit in a relatively similar set of planes and inclinations. A more likely scenario would be two similarly inclined orbits overlapping, with the satellites or debris impacting shallowly and at relatively (to orbital velocities, that is) low energy. It wouldn't take much to shred apart much of the more delicate instrumentation orbiting above our heads, which would similarly endanger more sensitive equipment, and so on.
https://swfound.org/media/6575/swf_iridium_cosmos_collision_...
"Analysis by both NASA and outside experts indicates that more than half of the Iridium debris will remain in orbit for at least 100 years, and much of the Cosmos debris will remain in orbit at least 20 to thirty years."
Purposely injecting debris into orbit, even if it's at a low orbit, seems not good!