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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]

#51

Post by Dylan16807 »

benchmarkist wrote: post #50
Dylan16807 wrote: post #47

Earlier quoted context omitted.

"True" here is not a boolean, it's the truth of the matter. The claim is that coordination is decreasing. Calling that "false" might mean coordination is steady. Calling it the "opposite of true" means that coordination is increasing .

That's a possible interpretation but the verbosity of the original statement hinders understanding the actual intent which is I why I recommended simplifying and removing unnecessary redundancies.

It's 40 words and makes three separate points in those words. I don't think it's too verbose, and I don't think your suggestion helps.

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

#52

Post by benchmarkist »

Dylan16807 wrote: post #51
benchmarkist wrote: post #50

Earlier quoted context omitted.

That's a possible interpretation but the verbosity of the original statement hinders understanding the actual intent which is I why I recommended simplifying and removing unnecessary redundancies.

It's 40 words and makes three separate points in those words. I don't think it's too verbose, and I don't think your suggestion helps.

Everyone is entitled to their opinions.

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

#53

Post by exabrial »

VLEO/LEO is the safest place to put satellites is it not? They'll eventually deorbit themselves if you do nothing, no?

The worst place for space junk is high orbits it would seem like. Earth was wildly visited by an Apollo rocket stage a few years back! That is pretty wild.

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

#54

Post by codeforafrica »

minetest2048 wrote: post #34
leptons wrote: post #27

Earlier quoted context omitted.

Sure, GPS is nice to have, but we lived without it for many centuries before it, it's also a "first-world-problem" if it goes down. GPS is also notoriously susceptible to ground-based jamming. And because of that there's also other ways to track position. Weather forecasts are nice to have, but often wrong. My original comment was framed more towards space travel.

The thing is that GPS doesn't just do positioning. If we lost GPS then we can just look at road signs (hopefully). GPS also provides time synchronization to a lot of very important telecom infrastructure. To prevent 4G base stations and digital TV transmitters from interfering with each other, their transmit reference clock frequency need to be disciplined to within 50 ppb and their time need to be synchronized to le…

And technology leapfrog effect means that third world countries will be significantly affected

Exactly that. In many parts of Africa the middle of nowhere is full of people. In many places mobile phones are the only way to get internet. I can't wait for starlink to be available here. Getting internet is not a first world problem.

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

#55

Post by vlovich123 »

to11mtm wrote: post #33
ljsprague wrote: post #32

Earlier quoted context omitted.

I would guess that it would still be possible to send things beyond earth's orbit with only a low probability of collision with debris but perhaps I'm wrong.

"Low" is tough to say until someone does some proper sort of 'true mapping' of space debris in the range somehow. Protection would require a lot of complexity and cost due to the need for shielding and the delta-v to move it up there.

Rather than protection on each rocket, couldn't you just send a bunch of fortified rockets that absorb the debris during a collision but don't emit anything. Do that a few times and then all other rockets just reuse the path that was cut?

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

#56

Post by mapt »

vlovich123 wrote: post #55
to11mtm wrote: post #33

Earlier quoted context omitted.

"Low" is tough to say until someone does some proper sort of 'true mapping' of space debris in the range somehow. Protection would require a lot of complexity and cost due to the need for shielding and the delta-v to move it up there.

Rather than protection on each rocket, couldn't you just send a bunch of fortified rockets that absorb the debris during a collision but don't emit anything. Do that a few times and then all other rockets just reuse the path that was cut?

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 dust... on a mixture of velocities, still circling your head. Now add a third bullet, also on a slightly different vector; Make sure that it doesn't collide with any of that dust!

The actual situation is we aren't dealing with 3 bullets or 100 bullets, we have ~170 million objects orbiting the Earth, and only around 50,000 are large enough to track. They are all moving fast enough in relation to each other that a collision would result in a sizable explosion, not an elastic agglomeration. We have no way of removing them.

The good news is that there is a large volume of space for them to exist in. The bad news is that as we continue to fill it up, odds of collisions increase, and every collision spawns many, many more objects.

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

#57

Post by mapt »

JumpCrisscross wrote: post #39
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…

> don't know how to sell the urgency of this predicament We need to start by understanding it. I'm having trouble finding this paper right now. But to date, all calculations have shown that Kessler syndrome as a generalised phenomenon is incredibly hard to trigger. Even intentionally. Especially in LEO. (Intentionally triggering it is of interest for strategic ASAT denial.) > the mass of potential impactors quickly f…

If 800km impacts go asymptotic, it pollutes 700km and 900km orbits by virtue of having a distribution of resulting debris velocity vectors, and as drag pulls down all the resulting debris over the next thousand years, the 800km debris becomes circular 700km debris, and then circular 600km debris, and then circular 500km debris.

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

#58

Post by nradov »

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…

There is no world in which giving cash or territory to the Chinese Communist Party would be acceptable to US taxpayers, regardless of the consequences.

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

#59

Post by nradov »

bamboozled wrote: post #17
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…

One way is for the the US to be more politically stable again (some how). Every country with an army will want its own star link now for trust reasons.

The US is politically stable already (by historical and international standards), and has been since 1865. If you ignore the rhetoric and focus on actions there has been very little substantiative difference in foreign policy across the last 7 presidential administrations.

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

#60

Post by blackeyeblitzar »

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…

Or just destroy their rockets and launch complexes. It’s better than Kessler syndrome.
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