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Astronomical Engineering: A Strategy for Modifying Planetary Orbits (2001)
- hirundo 5y agoThey propose steering a very large rock around the solar system to transfer momentum from Jupiter to Earth. The point is to increase the orbit of Earth to accommodate the brightening of the Sun over the next 10^9 years. So it's a long term global warming mitigation project. If the rock is big enough to do the job, the tides, earthquakes and volcanism around perigee could be inconvenient. Also, the power to set the gimbals on the rock is the power to extinguish the planet, and what organization could stay incorruptible for 10^9 years?
- lisper 5y agoThat was my first reaction as well: let's start mucking with earth's orbit, what could possibly go wrong? But the problem statement is trying to avoid being incinerated when the sun goes red-giant in a few billion years, so doing nothing is clearly not a viable alternative here. On the other hand, given our current blase response to climate change, I'll give you long odds against human civilization being around in a billion years, or even a million -- or, for that matter, a thousand. And unless something changes radically in the next few years, I'll give you even odds against it lasting to the end of this century.
- blacksmith_tb 5y agoI can't see how we'd call any descendants of ours 'human' in a billion (or even a million) years, but I would be surprised if modern humans were wiped out in the next thousand years - we've lasted tens of thousands up to now. We certainly need to make some changes, but I'm at least semi-optimistic we can do that.
- lisper 5y agoOh sure, humans will be around. But whether human civilization will be around is far less clear.
- reidjs 5y agoWhat makes you so sure about that? Humans require VERY specific environmental conditions to survive.
- shkkmo 5y agoHumans have thrived in a wider range of ecosystems and environments than any other mammal I know of. Humans have did this without a global industrial base using only local technology and economic output.
- LorenPechtel 5y agoActually, I would be amazed if "humans" exist at that point. I wouldn't be surprised if they don't exist in even a thousand years. Assuming we don't do ourselves in there will be sentients, but species are defined by the ability to interbreed and I expect genetic modification will reach the point that interbreeding with a stock human is no longer possible. At that point we will be a new species, not "human".
- lmilcin 5y agoIt is not global warming mitigation. This method has no hope of counteracting any kind of change in climate even on geological timescales. The only thing it can do is to slowly move Earth away from Sun over billions of years in imperceptible increments roughly every 6 thousand years. I hope humanity can even survive 6 thousand years.
- taneq 5y ago> and what organization could stay incorruptible for 10^9 years? I'd imagine after the first 10^8 years you'd probably have it sorted. Getting your organisation to last 10^2 to 10^3 years is the hard part.
- avaldes 5y ago> what organization could stay incorruptible for 10^9 years? Create a religion around the project, like the technicians priesthood in Asimov's Foundation or like in some proposals for long term protection of radioactive waste sites https://en.m.wikipedia.org/wiki/Long-time_nuclear_waste_warning_messages https://en.m.wikipedia.org/wiki/Long-time_nuclear_waste_warn...
- voakbasda 5y agoRight, because if there ever was a subset of humans that has never been corrupted, it’s the clergy…
- avaldes 5y agoIrrelevant in context. Priesthoods in the examples above are just structures to preserve and transmit the knowledge of their respective missions to future generations. However corrupted are real religions it can't be denied that they've been running under the same traditions and knowledge corpus for millennia, and that's the point.
- parksy 5y ago12000 years from now, Cockbert Roachstein, upon examining the peculiar dynamics of a passing moonlet, sets the scientific and philosophical community clicking and chirping with controversy on the suggestion that a mysterious ancient intelligence designed the scheme keep the planet's temperature in equilibrium as the sun heats up... "You mean to suggest a bunch of *click* _monkeys_ could steer the planet? Those creatures-in-the-dust who couldn't even survive _radiation_? You are hereby sentenced for *chirp* roach-heresy."
- causi 5y agoCombining the odds of us developing much better mitigation techniques if we survive the next million years with the odds of fucking this up and either ruining the moon's orbit or smashing the rock into the earth, this is an unbelievably bad idea.
- engineer_22 5y agoThere is no mitigation technique for being swallowed by the sun. It's a thought exercise, not a proposal, you need not be worried about a catastrophic collision. Bravo to the scientist for doing the calculations.
- LorenPechtel 5y agoThis *is* a mitigation technique for being swallowed by the sun--if we stay far enough away not to get too warm we also stay far enough away not to burn.
- perihelions 5y agoThis is so backwards-looking. Why on Earth would you go to all this trouble to preserve a planet intact, when with comparable* effort you could dismantle it entirely and create orders of magnitude more habitable ecology in the form of free-floating O'Neill cylinders? *(The solar gravity well is ~12 km/s deep and the Earth's gravity well is ~11 km/s, so dismantling the Earth and ejecting it are ~similar)
- azernik 5y agoEjecting and minor adjustments are very different things. Plus, the idea is to extract the energy from Jupiter's orbit.
- perihelions 5y ago>"Ejecting and minor adjustments are very different things." Sure, but going out to 1.5 au is already 1/3rd of the way to ejection.
- abecedarius 5y agoYes, and after that we ought to get started on dismantling the sun. The sun is offensively wasteful, not to mention short-lived.
- m4rtink 5y agoCase study from Orions Arm - the Turing dyson swarm: https://orionsarm.com/eg-article/49125f5d1c049 https://orionsarm.com/eg-article/49125f5d1c049 Effectively turning 2 class A white stars, 8 times as bright as Sol into computers, power plants and fuel for them, good for the next 14 trillion years: "Power spheres take the place of the more commonly used central star of most solar systems, but are far more efficient. The average Sol-type sun will convert only a tiny fraction of its total mass into energy in the course of a lifetime of approximately 10 billion years. The Power Sphere network of Turing is designed to provide an amount of energy equal to that of a sun but for a period of more than 14 trillion years." Or if you need more juice, say 100000x the output of the sun, you could sustain that for about 140 millions of years. ;-)
- sxp 5y agoThis seems very inefficient due to the high energy cost and the long timescales in the proposal. The long timescales means it would be hard to adapt this method to counteract rapid weather & climate fluctuations. A better option to control climate due to the sun would be to build a https://en.wikipedia.org/wiki/Space_sunshade https://en.wikipedia.org/wiki/Space_sunshade between Earth and the Sun. While the common design is a monolithic piece of metal to block the sun, a more practical design would involve a swarm of reflective robots flying in the appropriate set of orbits. They would be powered by solar panels and maneuver using solar sails to constantly adjust their orbits. That would allow your to block as much sunlight as you want and adjust the levels on a daily basis. You could also divert sunlight rather than blocking it which means you could increase the amount of sun the Earth gets if you want more light. Or you could use the swarm to focus sunlight on a certain part of the Earth while blocking light to other parts. This would allow for localized climate modification or even weather modification if you had a powerful enough supercomputer to predict the chaotic effects. Since you could adjust the light distribution on the order of days rather than centuries, there would be a lot more room for fine-grained control compared to orbital modification.
- montalbano 5y ago> supercomputer to predict the chaotic effects. This might be the hardest part of your proposal to achieve. Chaotic systems are fundamentally difficult to simulate, not just because of their differential equations but our lack of perfect knowledge of their initial conditions. Blanket solar reduction seems more feasible?
- pankajdoharey 5y agoI believe, much before those timescales humans would have become a Type 2 or Type 3 civilisation.
- Retric 5y agoA sunshade is almost feasible using current technology, though it would have some negative impacts. Solar Cruiser is a 1,672 m2 solar sail being sent to L1 for 65 million. Which is of course nowhere close to cost effective for lowering global temperatures, but the basic components are there.
- kavalec 5y agoThe future GOP will poo-poo the solar growth myth and complain about the effect on the economy.
- arthurcolle 5y agoDare I say "Galaxy brain engineering"
- renjimen 5y agoI love these kinds of planetary scale thought experiments. They must be a treasure trove for sci-fi writers. Imagine being on Earth living through one of the energy transfers. Reminds me of Asimov's Nightfall.
- hobscoop 5y agoIf only the US Forest Service knew about this, they could have properly answered Rep Louie Gohmert's questions!