How might reusable launch platforms affect strategic orbital postures?
My current guess is that with or without them, any major power war is likely to wind up with a lot of cheap gravel or even sand intersecting previously-useful orbits.
They’re all interesting points, but I think we’re a very long way from the satellite industry being a significant environmental concern.
Firstly reusable rockets cut the amount of discarded hardware massively. With expendable launchers almost all of the hardware dropped into the ocean or burned up is from the launcher. The satellite is a tiny fraction. This is a huge win.
Secondly the total mass of satellite hardware burning up is dwarfed by natural meteorites, of which approximately 100 tons of silicates, metals and hydrocarbons enters our atmosphere every day. That’s an entire ISS every 4 days. That’s 600 times the mass of satellites the US launches per year.
The thing is Starship may well increase mass to orbit by that much. Even so, that would “only” double the natural rate of material entering the atmosphere.
Another strategy that might help, for high altitude satellites, would be to move to fewer bigger satellites, with racks for different companies instruments, and with self de-orbit capability. Treat them like orbiting data centres. Starship can certainly handle big satellites, and if launches are cheap then it could be affordable to fit such satellites with de-orbit capability. Or maybe even send a Starship to swallow it up and bring it back.
Full reusability makes sense and limits space junk - though the counter to that is they are launching more satellites into space - so probably negate each other to a certain point.
I guess my concern would be who actually has regulatory authority over space and how can they ensure all actors play fairly. I would have to imagine this is a situation that is similar to the tragedy of the commons type scenario.
To be clear - I really don't fall into one side of the camp or the other but I can see how a lot of the waste management side of things can fall by the wayside given our track record on waste cleanup (mines, municipal solid waste, nuclear)
> Given the current situation, USA/SpaceX is in a far better position to quickly repopulate LEO with satellites when the debris has fallen down
It's far cheaper to heft tens of thousands of ball bearings into orbit vs a single satellite. You can give them a nice spread so you have a space shotgun that ruin an orbit for years at a time. The decay is a bonus to the attacker[1] because they can a go all out during wartime, without impacting their long-term space-faring program.
1. The decay also allows the same armaments to cover a larger vertical slice of the orbit.
De-orbiting satellites -- while necessary for well-discussed reasons -- seems wasteful. You spent umpteen million dollars getting that mass into orbit, and you're just going to drop it?
It's kind of like the plans to throw nuclear waste into the Sun, or more realistically into a deep ocean subduction zone -- isotopes that heavy or unstable are rare, do you know how much work it is to find them?
Having satellites is important to various industries and branches of government. As such, money and power will enable them to have satellites up there.
Even if we let Kessler syndrome run unchecked to the point of no return where it destroys a large portion of satellites, we will either start serious clean-up of certain orbits to allow military observation and communication satellites to go up again, or we will develop better collision avoidance or self-defence systems.
A great idea, but I wonder what Elon Musk's ideas about addressing the possibility of the Kessler syndrome; collisions between orbiting debris at an exponential pace ultimately leading to the denial of safe orbits to humanity.
Given SpaceX this is clearly something he should be deeply concerned about, but is he addressing it in any way, or just adding to the problem?
I'd say he is having a positive impact with his focus on reusable rocket stages, therefore less debris in orbit... a cloud of micro-satellites (how manueverable?) might be going in the other direction.
While this is fantastic news on one hand, it is concerning that cheap launches will lead to so much debris in low earth orbit that future generations will find it difficult to orbit without significant risk of micrometeorite strikes.
I think it's still valuable since we have tons of waste in our orbit that has already proven to be problematic. Maybe it's not cost effective if you only consider the cost of sending a new satellite vs the costs of repairing an old one, but if you take into account the reduced waste and the problems you avoid by having a cleaner orbit it may be worth the extra money.
> Very strange though, why does it need to be reusable?
Some people speculate that it is designed to take foreign satellites offline. Perhaps part of that mission is bringing them back to Earth to be analyzed.
Pure speculation, of course. Removing their solar panels so that they fit in the bay and then actually getting them inside seems complicated.
I'd be interested in seeing a deep dive analysis comparing the costs in energy / environmental impact, as well as risk profiles from space debris of maintaining clouds of lower-earth orbit satellite vs constellations of higher-earth orbit satellites.
For the lower orbits I think there are some points to be made about the additional flights to maintain enough satellites, as well as the questions of what happens to all this junk as it de-orbits? If we're talking about sustainable infrastructure, what kind of new weird material/chemical build-ups are we going to be dealing with after 50 years of tens/hundreds of thousands of private satellites partially burning up and partially raining down on random spots on the planet?
Perhaps this is less of an issue than I'm imagining it will be, but I tend to think we'd be better off figuring out some kind of autonomous robot LEO satellite aggregation/recapture solution for cleaning up satellites from higher stable orbits that can operate farther and live longer. We should be allocating our launches to other projects.
Even without considering the emissions of launches, there is a significant resource energy/cost for each one and the noise pollution also takes a toll on surrounding ecosystem. If we're going to be ramping up launches to scale the mass to orbit, we're also going to be scaling those negative externalities. I think we really need to make sure the mass we're taking up is worth it and not just governed by whoever happens to have the most money to burn.
I can imagine the very near future where people are paying to launch crypto-mining satellites for memes, or some other such wasteful nonsense.
Or, better yet, actually recycle that junk to build spacecraft and such. One of the biggest expenses of maintaining any sort of orbital infrastructure in the short term is the cost of sending raw material to space, but with all the raw material already floating around in space doing nothing but being a hazard to spacecraft, that could be readily solved.
Things placed in low earth orbit (where small launchers can put satellites) will de-orbit and burn up in 2-5 years from drag if they have no way to maintain their altitude. This isn't a problem future generations have to worry about. Geostationary orbit is a place where stuff can stay for thousands of years, so space junk build up could be a problem out there.
The downside, of course, is that your nuclear waste spends an awfully long time in an orbit that crosses, or at least passes very close to, Earth's. Better not lose control of your rocket, or you'll have a politically inconvenient situation on your hands.
> Even a fleck of shed paint a tenth of a millimeter across carries as much kinetic energy as a rifle bullet when it's traveling at orbital velocity,
Relative to an object stationary on the ground, yes. But every satellite is already moving at orbital velocity itself. If two satellites are orbiting in the same direction and one blows up, its pieces will not hit the other with full orbital velocity.
> any launch at all becomes a game of Russian roulette.
Maybe if the situation gets this bad, then the mitigation actually gets easier: just send up a lot of cheap big rockets on parabolic trajectories to orbital height. They will get hit, all the pieces will fall below orbital velocity, and fall down into the atmosphere. We could even launch cheap parabolic trajectory "blockers" to clear holes in the debris field for launches to higher orbits or escape trajectories.
The following is based on the assumption that more and more stuff is going into earth orbit over time.
As others have noted, putting satellites in lower orbits, below 500km or so, definitely helps with keeping things tidy.
Beyond that, robust regulation about ensuring that very little or no additional non-useful stuff is placed into orbit is also good. That is, require everything that isn't useful to deorbit right away or relatively quickly, and have the ability to deorbit at EOL.
What's beyond all that is the set of all things in orbits that aren't useful and that will naturally stay up there for a long time, in addition to any NEW stuff that's added, either by error or by accident. For example, a satellite in a 1000km orbit that has everything it needs to deorbit at the ends of its life, but fails to do so for whatever reason.
As others have noted, matching orbits is a lot harder than most people realize. Specifically, it's quite energy intensive.
At this point, basic physics tells us what we must do. In order to get long-lived, useless stuff out of orbit, we need to be able to send up specifically designed stuff, and a lot of it.
In summary: the most fundamental solution to this problem is to vastly decrease the price per kg to orbit. Regulation helps, but does nothing to clean up what's already there, and to resolve the unintended addition of new junk.
Summary to the summary: the newest crop of launch providers are aggressively working on this problem by aggressively pursuing reusability.
Slightly off topic, but is there any research going on regarding how to manage all the satellites being pushed into orbit? What happens when these things start to collide with other satellites or other trash accumulating in orbit? Is there a practical limit to what we can throw up into orbit before we start to see some adverse consequences?
Economics could solve it, if orbital manufacturing finds it cheaper to collect space junk for raw material than to boost it to orbit or mine it from asteroids. If we can defer it long enough to get to that stage an incipient orbital buzz saw may have a silver lining.
Tragedy of the commons I guess, but it's not exactly a new idea [0]. As long as they keep control of those satelites, keep them in high decay low altitude orbits and are able to deorbit them if necessary it's not exactly a huge problem, unlike random ASAT weapon tests or collisions that litter tiny untrackable particles that will stay there for centuries and rip through anything like butter.
My current guess is that with or without them, any major power war is likely to wind up with a lot of cheap gravel or even sand intersecting previously-useful orbits.
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