Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

youtube.com

Post reply on HN
Print view View original

21–30 of 162 posts

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

#21

Post by bragr »

akira2501 wrote: post #14
benchmarkist wrote: post #5

As long as it is militarily and commercially viable then the number of satellites will continue increasing, regardless of what academics have to say about collision rates. As per usual this is a coordination problem and in case people have not noticed nations are becoming less coordinated and more insular.

> in case people have not noticed nations are becoming less coordinated and more insular. And what is your yardstick for measuring this? As far as I can tell this is the opposite of true. It's a popular national news meme but I don't believe it's been measured in any reliable way.

I don't know about whether it is more or less common, but there has been international drama over conjunctions over the last several years

https://spacewatch.global/2021/12/spacewatchgl-share-chinese...

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

#22

Post by sfink »

ZYbCRq22HbJ2y7 wrote: post #15
jcgrillo wrote: post #13

Earlier quoted context omitted.

What would zapping a satellite with a laser achieve? I suppose if you get it hot enough to melt everything, without anything flying off, then it would turn into a spherical drop of molten scrap... but then what?

I assume the poster means to change its trajectory.

By adding energy (and momentum)? That seems unlikely to work. I guess you could try to shoot at things headed towards you over the horizon, to slow things down?

I was assuming it was to vaporize things to make the re-condensed remnants small and dispersed enough to be less of a problem. Though that seems like a tough problem if you have to stay trained on an orbiting bolt for any length of time, as the atmosphere wobbles your laser around.

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

#23

Post by leptons »

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…

>I don't know how to sell the urgency of this predicament. You can have as many satellites as you want, a million uncoordinated bodies, at 400km because direct collision potential scales with (satellite count / orbital lifespan) ^2 . At 1000km, satellites decay so slowly we are already too crowded; we have already overused the space. We are speed-running the end of the space age and we are doing it to save a small number of dollars and to avoid a small amount of diplomacy.

This sounds like the most first-world-problem ever. It realistically affects practically nobody alive, nor would it ever. Most people will live and die on the planet's surface and never visit space, nor do they need to. There aren't too many space-based services that are really necessary to life on earth. Nobody really needs internet in the middle of nowhere. Sure, it's nice to have, but that's a first world problem that few people have.

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

#25

Post by nwiswell »

leptons wrote: post #23
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…

>I don't know how to sell the urgency of this predicament. You can have as many satellites as you want, a million uncoordinated bodies, at 400km because direct collision potential scales with (satellite count / orbital lifespan) ^2 . At 1000km, satellites decay so slowly we are already too crowded; we have already overused the space. We are speed-running the end of the space age and we are doing it to save a small nu…

> It realistically affects practically nobody alive

Do people in the Global South not use GPS or consume weather forecasts?

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

#26

Post by aeternum »

jcgrillo wrote: post #13
Oarch wrote: post #10

There might be a cool storyline where we have to use enormous ground based lasers to clean up and start again. Could even look a bit like the iconic Gibraltar WW2 search lights photographs.

What would zapping a satellite with a laser achieve? I suppose if you get it hot enough to melt everything, without anything flying off, then it would turn into a spherical drop of molten scrap... but then what?

You ablate part of it on the prograde side to create a small retrograde thrust which will deorbit it.

I think the right move is to merge this approach with goo blobs. We launch a large goo blobs or nets into a few strategic geostationary orbits and now you only have to ablate objects so they hit the goo then deorbit the goo once it is full (or just leave it there) as they would be large known orbits.

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

#27

Post by leptons »

nwiswell wrote: post #25
leptons wrote: post #23

Earlier quoted context omitted.

>I don't know how to sell the urgency of this predicament. You can have as many satellites as you want, a million uncoordinated bodies, at 400km because direct collision potential scales with (satellite count / orbital lifespan) ^2 . At 1000km, satellites decay so slowly we are already too crowded; we have already overused the space. We are speed-running the end of the space age and we are doing it to save a small nu…

> It realistically affects practically nobody alive Do people in the Global South not use GPS or consume weather forecasts?

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.

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

#28

Post by throwaway314155 »

donaldihunter wrote: post #24

I love Sabine Hossenfelder's videos but the audio effects on the transitions are killing me.

They're a little too similar to my phone's built in sounds I suppose. Nothing I can't get over though. What about them is "killing you"?

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

#29

Post by ryankshaw »

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…

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’t ever launch any more things into space and become stuck. Trapped by the artifacts of their own progress

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

#30

Post by perihelions »

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 ground this discussion in diplomatic reality).

[0] https://www.scmp.com/news/china/science/article/3178939/chin... ("China military must be able to destroy Elon Musk’s Starlink satellites if they threaten national security: scientists")

Post reply on HN