Comment by jillesvangurp | Hacker News Reader

Comment by jillesvangurp | Hacker News Reader

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Space is more like international waters legally. The outer space treaty is rooted in maritime law principles. The Chinese and Russians are in no mood to slow down relative to the US. There will likely be some escalation in debris and damage resulting from that might eventually result in some kind of action. But most of the damage here would be economical and sending more stuff up is now very cheap. Manned flight is relatively infrequent and aside from the space station and very short lived space tourism, most activity in space is unmanned.

So, if a lot of satellites get taken out that's a problem but if a few get lost, nobody will care. The space station and other important stuff can be in relatively safe orbits. There's also the notion that a lot of the debris in low earth object comes down pretty quickly. Lots of unstable orbits. LEO is where most of the activity is for things like starlink and competing constellations. Which moderates the risk a bit.

SpaceX satellites are doing about 1000 collision avoidance maneuvers every single day. The addition of new networks is going to congest things even more and the risk of unavoidable cascading failure keeps increasing at a massive rate.

Those are pre-emptive moves for minimizing what is a very small chance of collisions, not narrowly escaped near certain collisions. Air traffic control does a similar thing with keeping planes spaced apart in zones under their control. In space a small thruster nudge will have a huge impact at a very low cost

I learned that within the 2 hour launch window for Artemis 2 there were many blackout periods ranging from seconds to minutes for collision avoidance.

At some point they need to remove all the objects that can't do 1000 collision avoidance maneuvers per day.

No, they do not actually, because they fall out of orbit in ~5 years, since they're in the lower part of the thermosphere.

> SpaceX satellites are doing about 1000 collision avoidance maneuvers every single day

Genuine question: how many avoidance maneouvres does maritime traffic execute in the open ocean?

The blast radius from a maritime collission is (mostly) relegated to the vehicles in question [1]. The same is not true for satellite collisions.

[1] There are counterexamples, like in narrow chokes & whatnot.

> same is not true for satellite collisions

Space is big. Volume grows with radius in a way our intutiions don't seem to intuitively understand. Yes, debris in a space collision go further. But they're still bound by their energies. And that larger volume of collision debris (plus all other stuff in orbit minus the Moon) is still a smaller fraction of the orbital space than e.g. commercial air space on earth, and yes, that's including oceans.

Space is huge, but being on land has some advantages too. It's true that volume grows, but satellites don't have brakes in the way that cars do, nor is there a cleanup crew that removes the debris after a crash.

You can remove curbs and any other barrier to simulate the fact that cars can maneuver away from a crash site, but if no site is ever cleaned, and no car has meaningful brakes, crash sites are much scarier.

I wonder how many collision avoidance maneuvers are performed every day by human drivers. It must be in the trillions.

Loads of those result in crashes with some involving hundreds of cars.

Just one collision in space carries an ever-increasing risk of cascading into a major event with long-term effects (there's no a good way to call in a space wrecker to haul billions of tiny bits out of orbit).

That depends what you mean by "open ocean"? Vessels near ports or in defined traffic lanes frequently maneuver to avoid collisions as per the rules of the road. Outside territorial waters it's less common but still happens occasionally. Either way, those avoidance maneuvers are such routine events that no one really gathers data on them.

Debris from a collision on water won't spread out into millions of floating pieces that speed around faster than a bullet, ripping random ships on the other side of the world to shreds.

> spread out into millions of floating pieces that speed around faster than a bullet, ripping random ships on the other side of the world to shreds

This isn't how debris clouds work. The most-complex ones occur when entirely separate orbits collide were you get an X-shaped (versus cylndricla or conic) debris cloud. But the energies of the collision inputs sharply curtail the orbits and places in said orbits the debris fragments can generally reach.

Idk, Iridium-Cosmos debris are still absolutely everywhere [0] after almost 20 years. The only place a ship collision's gonna leave debris is directly under it.

[0] https://ajmas.github.io/StuffInSpace

> The Chinese and Russians are in no mood to slow down relative to the US.

Typical boogeyman fearmongering to justify the existence and expansion of the US military industrial complex.

Out of all these three (US, China, Russia), a simple count of who has started more wars and conflicts is a clear indicator of who is the one initiating the vicious cycle of aggression and "defense" budgets.

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