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New Calculation Finds we are close to the Kessler Syndrome [video]

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Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#111

Post by m4rtink »

lxgr wrote: post #65
ryankshaw wrote: post #29

Earlier quoted context omitted.

Is Kessler syndrome the Great Filter ( https://en.wikipedia.org/wiki/Great_Filter )? As in, is it the thing that makes it so no one else has broken out of their planet to come visit us? I could totally see it being the case that as soon as a civilization gets good enough at putting stuff into space, they start putting a lot of stuff into space and then things start crashing into each other to the point that they can’…

I'd consider it much less likely than e.g. nuclear or maybe chemical/biological warfare. Kessler syndrome (if even achievable with current technology) would be a major bummer for science and the global economy for a couple of decades (no more Starlink, but we still have good old geostationary satellites, so no ships and airplanes would get disconnected as a result), or at worst centuries, but would otherwise not form…

I think it would be actually the other way around - Starlink orbits aee low enough to be self cleaning & Starlink satellites can be (and are) rapidly replenished. So even if something from up above hits anfew, the debris would deorbit soon & new ones could be launched.

With GEO sats, unless you go for direct GEO insertion, it might still have issues reaching the final orbit. And even at GEO, there could be a debris cloud as well causing issues, at least until the sun and moon gravity perturbs it enough.

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#112

Post by m4rtink »

maxglute wrote: post #38
perihelions wrote: post #30

Earlier quoted context omitted.

Why would any of the US' adversaries agree to that? We have SpaceX, and they do not; lowering the altitude of megaconstellations is asymmetrically far more costly for them then it is for us. Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility. (It's even their declared planning that deliberate Kessler cascades are on the table [0]—to try to…

I think OP is suggesting US concede to sharing 500km orbits that SpaceX has disproportionately squatted rights to, since current international law is first come first serve. Where concede is to rejigger international law to increase density of 500km so others wouldn't have to go higher, i.e. PRC mega constellations going ~800 because ~500 mostly taken. Or in ops suggestion, free for all. This is more costly for US si…

Others would use theblower orbits - but it is just not viable for them, as their rockets suck (eq. are not reusable) and thus they need to put their few expensive satellites with meager propulsion capabilities higher to last longer. Not to mention spot beams being wide enough with so few satellites.

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#113

Post by LoganDark »

vlovich123 wrote: post #104
immibis wrote: post #71

Earlier quoted context omitted.

It takes about 90 minutes to complete a low earth orbit. A rocket can't hover in place for 90 minutes at the same altitude, then increase its altitude by its height and repeat. It doesn't have enough fuel for that.

Go the other way. Attain maximum altitude and then descend slowly. You don’t need to do this with just one rocket. This would be a clearing exercise composed of multiple rockets.

This sounds like it would almost work in a 2D universe.

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#114

Post by perihelions »

mapt wrote: post #48
perihelions wrote: post #30

Earlier quoted context omitted.

Why would any of the US' adversaries agree to that? We have SpaceX, and they do not; lowering the altitude of megaconstellations is asymmetrically far more costly for them then it is for us. Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility. (It's even their declared planning that deliberate Kessler cascades are on the table [0]—to try to…

Invite them in. Launch their satellites for them, at 400km. Give them cash or territory. Give away the farm. How doesn't matter. What matters is that we start coexisting at 300-500km, and we mutually taboo launching large amounts to altitudes much higher than that. There is no stable Mutually Assured Destruction Nash equilibrium here, if either of us does this thing it causes dramatic harm to both. Not regarding that…

Not agreeing with any of this.

- "Launch their satellites for them, at 400km."

No reasonable person would help their adversary build powerful weapons that could immediately be used against them. The point of satellite constellations—Chinese or American, either—is to create undeniable, high-bandwidth communications for armies; to create real-time (as opposed to sporadic) satellite imagery for armies; to create, in short, an overwhelming situational awareness advantage in a conventional war.

- "Give them cash or territory."

We are not giving away countries.

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#115

Post by lupusreal »

perihelions wrote: post #30
mapt wrote: post #8

The current trajectory is that SpaceX proved the commercial and military viability of an LEO megaconstellation, repeatedly lowering their target altitudes and raising their satellite count because of debris and cell size concerns... And now the rest of the world is trying to catch up in a sort of arms race, and not taking any care about debris concerns. The most tempting orbits are the ones in upper LEO that permit t…

Why would any of the US' adversaries agree to that? We have SpaceX, and they do not; lowering the altitude of megaconstellations is asymmetrically far more costly for them then it is for us. Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility. (It's even their declared planning that deliberate Kessler cascades are on the table [0]—to try to…

> Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility.

Put 100k boost-phase interceptors into LEO. Permit them a fixed quota of launches per year, shoot down the rest. Pax Americana.

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#116

Post by perihelions »

m4rtink wrote: post #111
lxgr wrote: post #65

Earlier quoted context omitted.

I'd consider it much less likely than e.g. nuclear or maybe chemical/biological warfare. Kessler syndrome (if even achievable with current technology) would be a major bummer for science and the global economy for a couple of decades (no more Starlink, but we still have good old geostationary satellites, so no ships and airplanes would get disconnected as a result), or at worst centuries, but would otherwise not form…

I think it would be actually the other way around - Starlink orbits aee low enough to be self cleaning & Starlink satellites can be (and are) rapidly replenished. So even if something from up above hits anfew, the debris would deorbit soon & new ones could be launched. With GEO sats, unless you go for direct GEO insertion, it might still have issues reaching the final orbit. And even at GEO, there could be a debris c…

- "And even at GEO, there could be a debris cloud as well causing issues, at least until the sun and moon gravity perturbs it enough."

Not a satellite expert, but I understand GEO clears out relatively fast (~decades), because of those 3-body perturbations,

https://www.agi.com/blog/2020/07/geo-satellites-don-t-decay-...

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#117

Post by poulpy123 »

lupusreal wrote: post #115
perihelions wrote: post #30

Earlier quoted context omitted.

Why would any of the US' adversaries agree to that? We have SpaceX, and they do not; lowering the altitude of megaconstellations is asymmetrically far more costly for them then it is for us. Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility. (It's even their declared planning that deliberate Kessler cascades are on the table [0]—to try to…

> Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility. Put 100k boost-phase interceptors into LEO. Permit them a fixed quota of launches per year, shoot down the rest. Pax Americana.

you mean total nuclear war

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#118

Post by perihelions »

lupusreal wrote: post #115
perihelions wrote: post #30

Earlier quoted context omitted.

Why would any of the US' adversaries agree to that? We have SpaceX, and they do not; lowering the altitude of megaconstellations is asymmetrically far more costly for them then it is for us. Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility. (It's even their declared planning that deliberate Kessler cascades are on the table [0]—to try to…

> Stopping China's (highly strategic, military) satellite constellations isn't a "small amount of diplomacy". It's an impossibility. Put 100k boost-phase interceptors into LEO. Permit them a fixed quota of launches per year, shoot down the rest. Pax Americana.

Then they'd retaliate in kind, and we'd get nowhere. It's certain they have that capability, or can develop it.

We stand to lose a lot more from a space war, right now, than anyone else. We (US/west) hold the lion's share of space commerce and orbital launch capacity. "Earth orbit is free and open for everyone" is more than Star Trek idealism—it's a precedent we've set that benefits us, especially.

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#119

Post by ben_w »

vlovich123 wrote: post #62
mapt wrote: post #56

Earlier quoted context omitted.

Orbit is not a location. Orbit is a group of velocity-location vectors which form a stable loop around a body, without intersecting that body. Imagine a bullet circling your head at mach 25. Now imagine a second bullet, circling your head at a slightly different angle, at a slightly different distance from your head. There's a chance that they could collide, and the resulting explosion would leave a great deal of dus…

You’ve explained what Kessler syndrome is but not why my idea doesn’t work. I’m saying send reinforced rockets through the orbits that absorb the collision instead of generating more dust. That should let you clear a path through all orbits that intersect your path. It’s hard to do and the 3d aspect of it might make it expensive but conceptually it could be a solution. Or use super powerful lasers (potentially mounte…

> I’m saying send reinforced rockets through the orbits that absorb the collision instead of generating more dust. That should let you clear a path through all orbits that intersect your path.

No such material exists, nor can it be made from any matter that is based on electrons bound around a nucleus — the force of impact will break any such material.

> It’s hard to do and the 3d aspect of it might make it expensive but conceptually it could be a solution.

"expensive but conceptually it could be a solution" is also why we don't have an Orbital Ring instead of rockets: https://en.wikipedia.org/wiki/Orbital_ring

The cost requirement for getting something to space with enough momentum to do the cleanup, even if it was able to survive the impacts, would be comparable to the entire cost of getting the stuff constituting the mess into orbit in the first place: bad enough to be prohibitive even today with relatively little mess, much worse if there's an actual Kessler cascade.

> Or use super powerful lasers (potentially mounted on a satellite) to deorbit the dust

Could work for the bigger bits, but don't put the lasers on a satellite: 1) Power is short up there, as is cooling, much easier to put a bit laser on the ground and waste some energy going up through the atmosphere; 2) if you solve that constraint, you've now got an orbital laser that's an obvious and easy-to-hit target for all foreign powers to get upset about even if you didn't want to weaponise it.

For the smaller stuff, you can't see the dust to target it in the first place.

Re: New Calculation Finds we are close to the Kessler Syndrome [video]

#120

Post by throwaway290 »

neilv wrote: post #85
blackeyeblitzar wrote: post #61

Earlier quoted context omitted.

[flagged]

Please don't commit acts of war. War is bad.

"Please don't hurt the bully in the playground, fighting is bad"

The bully isn't going to learn with this implicit encouragement.

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