The degree of exponential growth is still in question but the fact that it will be exponential, and will cause a huge headache eventually if left unchecked is pretty much accepted.

However, enforcement would run into the same problem that enforcing any resource in the international commons runs into, such as overfishing, oceanic/atmospheric pollution, etc.

Since it requires coordinated collective action of every space launching nation, it would require something like the UN security council to really punish nations that defect from the agreed upon program. which opens another can of worms.

Geosynchronous orbit is quite packed, but everything is moving in the same direction which prevents the kind of exponential cascade that’s so concerning. Above geosynchronous orbit’s graveyard stays clear simply because little has the energy to reach that altitude.

Regarding simply transiting through our ex-satellite rings, I don't think there is consensus. Would it make launches beyond LEO practically impossible, or just theoretically risky in the way that blindly navigating the asteroid belt is? (You could hit something, but it's so little matter dispersed over so much space it'll probably just be extremely fine dust the shielding can handle. Probably.)

For example: two satellites collide head-on at an altitude of 300km, creating two debris clouds that extend from 250km to 350km. Each of those catches another satellite, one at 260km and another at 320km, which fragment into debris clouds reaching from 200km to 370km (all numbers made up).

Higher orbits, like geosynchronous, have a lot more space to work with and much slower relative velocities than low Earth orbits.

At 300km satellites experience significant drag and need regular boosts to maintain orbit. After collision individual objects orbit will almost always include it’s altitude at the point of impact and generally expends above and below that point. So while yes the cloud extends to higher orbit, everything would deorbit from your example extremely quickly.

The situation is neither pro- nor anti- our ability to organise at a mass level. This has been a remarkable 2 years to be alive and we've seen a level of urgent response that has never been achieved before, ever. With 3 years to prepare, anything is possible for this Kessler business.

Thats pretty fucking simple science, is it not?

First, it's not just satellites. There's hundreds of thousands of pieces the size of a marble that'll cause catastrophic damage. And even more smaller pieces, even millimetre long bits of paint have caused damage to vessels.

Second, harvesting (presuming you mean recovery) or just killing (presuming you mean de-orbiting with atmospheric burn up) require expending deltaV. There has been some interesting proposals for using laser ablation or tether based systems, but nothing that I know of that has gone past a paper proposal.

Detonating just adds to the problem.

The problem is 'What happens when the plan fails due to design errors/bugs/accidents/breakages/etc'.

Recovery of a satellite is incredibly expensive.

We need both space junk recovery and ocean plastic recovery robots.

Recall that startup that tried to launch the ocean plastic/garbage gyre bot and it failed and no mega-corp tried to save them.

if anyone should be forced to help on this effort, it should be amazon/bezos

The problem isn't that we're no longer able to launch new rockets - it's that anything in space comes to a standstill when it gets destroyed. How about GPS is suddenly no longer usable, with planes in flight and ships somewhere on the ocean? Weather satellites allow no more observation, with no more forewarning for hurricanes, and no reliable planning of routes by either plane or ship. What will be the impact of both on modern agriculture? No more satellite based communication, etc.

I meant world scale extinction event like https://en.m.wikipedia.org/wiki/Cretaceous–Paleogene_extinct... . A layer of sediment literally everywhere, etc.

How do you call, say, a disease that kills half of all humans? An inconvenience?

> Of course, it could be "catastrophic" too, but there is catastrophe, and then there is catastrophe...

> How about GPS is suddenly no longer usable, with planes in flight and ships somewhere on the ocean?

Anything over land can be replaced by antennas sending out a signal from a known location, and receivers can triangulate their position from that. In-flight planes can use landmark plus compass based navigation, as well as (already existing) ground based navigation beacons, and pilots are trained on how to deal with all instruments gone dark scenarios. Ships can sail along land and use sextant navigation on the open seas (actually, the US Navy re-introduced training sailors in sextant use in 2016, to account for a no-electronics scenario!).

> Weather satellites allow no more observation, with no more forewarning for hurricanes, and no reliable planning of routes by either plane or ship.

The worst loss will be for everything over the open sea, but land based weather documentation will still be possible.

> What will be the impact of both on modern agriculture?

Not too much, technically we can gather everything agriculture needs from the ground, it's just way more effective and cheaper to observe from space.

> No more satellite based communication, etc.

That would not be a big loss, there exist (long forgotten outside of amateur radio) technologies to deal with that.

And sure, ‘solutions’ will be found. Here’s another one for your list that will diminish the impact of the loss of weather satellites: just strap someone to a weather balloon and have them draw what they see, and drop those drawings until the person runs out of oxygen. Is it as powerful/convenient as what we have today? Hardly.

However, if we experience a catastrophic problem in space, we’ll have to deal with all of them simultaneously, with extreme time pressures.

And one trap here is we must have a we. The old way is to say it must be a collective joint action is not right. There is a reason why we have carbon tax, which is a market solution to a commons issue. Not I am saying you can do that. But individual countries as individuals should be an option.

Sometimes there is no we. We may want to no we as well sometimes ;-)