https://www.extremetech.com/extreme/245369-nasa-proposes-bui...
I think we have no chance at the large space structures, and current age will be considered a fluke of the insufficient lifting capabilities.
We're decent at tracking large space rocks, and small space rocks will likely have to be dealt with anyway since some occur randomly.
It's somewhat interesting that terrorism already isn't such a problem for huge skyscrapers. Skyscrapers can be destroyed with just a small fraction of the explosive energy required to launch an orbital rocket yet it rarely happens.
and inertia is a bitch
you have to choose to hit something, because the energy to completely eject that mass from being dangerous would be a lot
Also "throwing space rocks will be trivial for a terrorist cell" makes a lot of presumptions about how social organization will work in orbit. IMHO there will never be the spacer society presupposed by so much sci-fi, because any spaceship with an interesting propulsion system is also always a weapon of mass destruction (and not just against orbital infrastructure). The solution to this is that weapons of mass destruction are only owned and operated by large, powerful states with things to lose. It's worked for nukes for 80 years soonish.
So, yes, there won't be some independent spacer terror cell. But what if one of the space faring countries will decide to simply sponsor some Hamas 2.0 to attack their opponents? Considering that this will be a new age of conquest possibly, where nothing in the Solar System is yet owned by anyone and there will be a lot of takers. Like a simplest question - who's are Luna and Mars? :)
Next issue is that chemical rockets are much simpler and cheaper, also they are not gated by any tech or material. Sure, there are important secrets around nozzles and stuff, but I suppose a simple crude rocket will work just fine. So assuming we are at the level when humans can travel to the asteroids to mine them (also a big if, due to it being economically unfeasible) they can setup such a kamikaze rocket. Attack will be from outside of the ecliptic plane, so likely undetected. Attack can be scaled to more than one rock, so that every single point of failure, every dome etc must have dozens of anti-spacecraft level defense rockets (nukes most likely). It is not feasible.
Of course all of this is about far far future, we can't predict what will happen.
It won't be. There is no stealth in space, and telescopes are really good. Once there will be a lot of man-made objects in space, it will be trivial for a state actor to continuously track the exact position (and complete history) of every single man-made object large enough to have an engine in the solar system, and I would assume that everyone with major space interests would do that.
ICBMs have existed for a long time, as have nuclear weapons. Terrorists cannot "trivially" deploy them.
These kind of extremely powerful magnets will not be trivial, and doing anything in space even less so.
You were talking about the "total destruction" of the ecosystem on Earth, because "throwing space rocks" will be "trivial for any terrorist cell". Talk about hypothetical rockets fired on hypothetical domes on a hypothetical Mars colony bears absolutely zero relation to that.
Unfortunately, humans tend not to put much effort into anything that has no benefits within ~100 years. "If neither me nor my children will benefit from something, I don't want to invest my time/money."
At some point your descendants will be too far to remember the reason but not far enough to need it and they’ll stop wasting resources on a nothing activity.
Then in 10,000 years, find that an entire religion, culture, and wars were built around the simple maintenance instructions.
So we have to assume we will maintain the ability for human Mars travel in ten thousand years, that anyone can read English or whatever in ten thousand years, and that the supporting religion didn’t lose any of its wars.
To put this in perspective our first evidence of any human agriculture was 12,000 years ago.
We can't even fix the problems on our first planet. How (and why) can we even begin to think about another one?
(Not to mention that solving Mars problems are likely to yield novel solutions to Earth problems, ones which we might never discover without thinking about things with an unusual perspective.)
These existing solutions are already on an exponential growth curve and cost decline. They have been for ages. We're on the right path right now; sadly most people find it difficult to see ahead beyond linear growth.
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[To be clear, here I am responding to the challenge of bringing greenhouse gases emissions to a level which ends the rise of global CO2. It's a solved problem with lag time. The collapse of biodiversity is the political and sociological problem I referred to in a previous post.]
Scale is the problem.
> Once we have enough solar panels, wind turbines and battery cells, a tipping point is reached where the cost of renewable energy plummets so hard that fossil fuel energy becomes catastrophically uneconomical
The radical change I'm referring to is the drastic cut in energy consumption to make renewables work at our current scale. I suggest you have a look at the latest IPCC report [0]: we won't be carbon neutral without reducing our energy consumption, not "simply" replacing a source by another for each use, reducing it. That means doing less things, which no one plans on doing.
Not even to mention that some non negligible parts of our economy don't have a technical solution yet, the aviation industry for instance.
> a solved problem with lag time
I don't understand what you mean by that as it seems we are not on the right trajectory to avoid a catastrophic outcome...
[0] https://www.ipcc.ch/report/sixth-assessment-report-cycle/
Unnecessary. You’re thinking linearly. We don’t need to cut energy consumption, it will be met and exceeded by the current exponential growth of renewables and storage. The “we have to do less” crowd are wrong and bad at math.
Aviation isn’t a solved problem yet but that’s still less than 3 percent of fossil fuel sourced greenhouse gas emissions. There are far more pressing concerns like banning domestic fireplaces.
I would be more concerned about the ocean shipping industry, one which is just screaming out for nuclearisation, but of course that would be protested by ignorant faux-environmentalists who care more about telling others what to do than what’s actually good for the planet. (For some light entertainment, read up about fractional distillation and learn about exactly what it is most cargo ships burn. It ain’t avgas, that’s for sure. But nobody cares because intercontinental trade doesn’t work as well as commercial aviation as a target for class warfare.)
> That means doing less things, which no one plans on doing.
No one plans on doing that right now. But once we divert the attention of astrochemists away from studying the terraforming of Mars and towards the intersection of politics and sociology, I’m sure they’ll come up with the solution.
> it seems we are not on the right trajectory
It would seem that way if you think linearly.
Physics, not maths. You can sustain exponential growth as much as you want without physical limits. If that's where your confusion comes from, you can read some vintage Meadows.
> It would seem that way if you think linearly.
Even the optimistic scenarii put us in a bad position... ignore evidence as much as you want, it won't make it true.
For precisely this reason?
We can't stop asteroid impacts. We can't stop a well-adapted plague, either (Ref: Covidiots). We have dictators with nuclear weapons that we can't stop. etc.
Having a self-sufficient colony somewhere other than Terra is almost certainly the first step toward avoiding a "Great Filter" event.
By this logic we never go. There will always be giant seemingly insurmountable problems. If we solve climate change there will just be another, and another, and another. Life is a never ending fight against entropy. There will never be a time when we have it all figured out.
Secondly it’s entirely possible that the stuff we learn trying to survive off world will be applicable to making life here more sustainable. It could force us to figure out how to run industry efficiently with a very high percentage of material recycled, and how to run an economy without a lot of low entropy ecosystem to draw from. Also no fossil fuel. They don’t exist. We’d only have nuclear and solar really.
They could have made it a bit weaker, not bothered with paint or inspection hatches, and saved a little money, and had it only last 25 years...
The time-value of money says that any benefit 25+ years from now is almost worthless, so it probably wasn't worth spending anything on those things to make the bridge last longer.
Yet in most cases we still tend to build it to last 100 years, despite the economist saying it isn't worth it.
A better example are maybe tree avenues that take decades to grow into anything useful, or maybe long term river redirection projects or reactors. ITER's still in construction after 16 years. But there's just about nothing we do that would take more than a few decades to start showing returns.