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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]

#81

Post by shiroiushi »

tehjoker wrote: post #75
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…

basically, it sounds like the U.S. should not treat China as a competitor and we should cooperate. this insane hypercompetition for literally no reason (other than US capitalists wanting to remain dominant) is going to destroy us all.

You think the Chinese capitalists aren't also trying to become dominant?

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

#82

Post by wbl »

JumpCrisscross wrote: post #63
mapt wrote: post #57

Earlier quoted context omitted.

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.

> 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 Circularisation isn’t the unexpected part. Sphericalisation is. One requires orbits to desync. The other requires plane changes.

There is percession of the perigee.

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

#83

Post by resters »

lxgr wrote: post #64
resters wrote: post #18

Positioning a large, armored satellite in low or mid-Earth orbit significantly enhances its strategic value for both offensive and defensive anti-satellite operations. Such a platform could serve as a pivotal asset in maintaining orbital dominance, offering rapid response capabilities to neutralize threats and protect critical infrastructure. In other words, welcome various "death stars" to keep order against malicio…

What do you assume happens to a "neutralized threat" in terms of space junk?

Perhaps it is recycled aboard the large armored satellite or propelled into the Earth's atmosphere so it can burn up.

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

#84

Post by aidenn0 »

0xbadc0de5 wrote: post #16

My understanding was always that LEO is much less of a Kessler risk due to atmospheric friction - ie: in the absence of active control and regular correction, LEO objects will gradually de-orbit themselves. It's the the higher geostationary orbits that pose the problem.

Depends on where in LEO. Explorer I had a perigree of about 350km and lasted for 12 years, though the orbit was highly elliptical. 900km and above is stable for thousands of years and well within the (circular orbit) LEO ceiling of 2000km.

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

#85

Post by neilv »

blackeyeblitzar wrote: post #61
mapt wrote: post #48

Earlier quoted context omitted.

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…

[flagged]

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

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

#86

Post by bagels »

resters wrote: post #18

Positioning a large, armored satellite in low or mid-Earth orbit significantly enhances its strategic value for both offensive and defensive anti-satellite operations. Such a platform could serve as a pivotal asset in maintaining orbital dominance, offering rapid response capabilities to neutralize threats and protect critical infrastructure. In other words, welcome various "death stars" to keep order against malicio…

"armored"

I don't get the impression that you've looked at the physics of orbits.

Everything up there carries tremendous kinetic energy.

It would be pretty hard to build something strong enough to take on intentional collisions, let alone large debris.

Fun reading: https://www.esa.int/Space_Safety/Space_Debris/Hypervelocity_...

Here's a picture to illustrate: https://www.esa.int/var/esa/storage/images/esa_multimedia/im...

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

#87

Post by lmm »

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?

> couldn't you just send a bunch of fortified rockets that absorb the debris during a collision but don't emit anything.

"Just" how? Orbital collisions happen at an average of 10km/s, you're going to make what, some kind of sponge that can get hit by a chunk of satellite going ~8x faster than a bullet and absorb it and slow it to a halt without fragmenting at all? Good luck.

> Do that a few times and then all other rockets just reuse the path that was cut?

Things in orbit are constantly moving, you can't "clear a path" any more than you can, IDK, make a safe route through a forest by walking through it once and moving any bears you encounter a couple of feet.

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

#88

Post by lmm »

nradov wrote: post #59
bamboozled wrote: post #17

Earlier quoted context omitted.

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.

Going from a treaty and cooperation with Iran to cutting them off was a pretty substantial change that has already had global implications.

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

#89

Post by aaron695 »

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…

[dead]

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

#90

Post by [deleted] »

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…

[deleted]
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