Scenario is that at some point in the near future an alien spaceship lands in one of the worlds capital cities, its occupants are here with a warning, but they can’t stick around to help as they need to leave immediately for the next inhabited world to deliver the same message.
They state, and provide convincing proof, that an ancient and extremely powerful weapon is on its way, it is the remnant of a conflict from before humanity or the aliens time, they have tried but are unable to destroy it. It has one purpose only, to destroy technological civilisation where it finds it, if it doesn’t notice anything it will simply pass on through the Solar System. It conducts initial scanning from space and only if something piques its interest will it drop physical probes directly onto a planet or moon of interest.
The aliens aren’t sure how it functions exactly and can’t give much more advice other than ‘hide’, they are very clear that humanity shouldn’t attempt to communicate with or destroy the weapon. They aren’t sure how sensitive its detecting instruments are but state that they suspect that radio signals from Earth caused it to home in on the Solar System.
They state humanity has roughly ten years to prepare and the weapon will be in the Solar System for approximately five weeks before passing through…or not, with the danger increasing the closer it gets to Earth.
So, would it be possible for humanity to hide technological civilisation? Or is it a doomed cause from the start? How would you even begin?
Well, it all depends on that unknown sensitivity of the sensors. If they were very crude, there is some chance that if we intentionally completely fucked up our atmosphere so that there was 100% cloud cover, they might not notice. But that would require that they not notice any of the satellite debris orbiting the Earth (even if we could deorbit the satellites, we couldn’t get rid of that) and not notice all the spacecraft in orbits around and on the surface of various planets, moons, asteroids, and comets, or the markings left behind by said spacecraft. (Miles of tread marks, for example.)
They would have to be pretty damn lousy berserkers to miss all of that.
If its primary criterion is radio, we’re fucked. You just know some “burn it down” type will deliberately transmit. Plus I don’t think we can tell the Voyager probes to shut up.
Even if we stop transmitting right now there’s still a hollow sphere of radio waves expanding at the speed of light. There’s no way to call that back, and no way to get in front of it to block it. We’re boned.
The preamble is different, but there is a novel (maybe novella) with a very similar plot. The weapon works off detecting radio wavelengths so all humanity has to do is stop using radio. In the story this proves difficult as some of humanity view the oncoming entity as a benevolent alien. The humans decoy and divert the weapon with a powerful transmitter which they send off into space for the weapon to chase. I also recall human-created AIs being involved somehow.
There are powerful organizations of people who aren’t even convinced that the world was created more than 8,000 years ago. How do we convince them to shut down their massive array of super-powerful radio transmitters blabbing endlessly (as they’ve been commanded to do by their Almighty) on every spectrum?
Regardless of the chosen strategy, there will be naysayers with the power to foil our effort to hide.
I believe it becomes increasingly attenuated with distance, in which case the other party would need an incredibly powerful/huge receiver (pointed in the correct direction too).
I don’t think it can be done in 10 years, even if all humans believed the aliens (which they won’t).
Let’s suppose that a level of development equivalent to the year 1800 is enough to fool the probe. Basically: no electricity, no petrol, no nuclear power.
You have to destroy or hide all modern roads, dams, bridges, maybe tunnels. All buildings above 3 or 4 stories, except for churches, temples and pyramids. All electrical lines, pylons and transformers, and all power stations (how long does it take to decommission a nuclear power station?). Cars, trucks, bulldozers, trains, airplanes. Open-air mines. Refineries. Railways, airports, spaceports. All ships powered by oil or nuclear fuel. (How do you hide a super-Panamax ship? An aircraft carrier? A drilling platform? An off-shore wind farm? Is it enough to just sink them?)
And you have to build many sailing or rowing ships.
Ah, confound it. I, for one, welcome our new alien overBOOOOOM
The grim solution: get every nuclear warhead in the world fully operational again and mount them on missiles, etc.
While this is happening, the governments of nuclear countries arrange to sequester themselves and a population of educated citizens sufficiently large to repopulate easily with enough skillsets to rebuild society represented among them, as well as databanks containing as much human knowledge as possible.
As soon as this is done, launch the missiles. The objective is to nuke every single square kilometer of Earth that has human habitation; we want to obliterate the population outside these secure bunkers. Also, do some high-altitude detonations to make sure every square kilometer of earth is hit by an EMP, and so are all orbiting satellites.
Now, sit tight and quiet in the secure facilities. Hope that, when the alien device arrives, it sees that humanity has destroyed itself, and moves on without conducting a more detailed search.
Agreed - I think we’d be screwed, just because the failure factor is so very small. By careful planning and brutal enforcement, we could probably eliminate upwards of 99% of all radio comms, but all it takes is one fuckwit with a Ham radio, or just the parts to make a rudimentary transmitter.
In addition to ‘burn it down’ types, you’ve got conspiracy nuts, who will not accept the rationale for the radio silence at face value, and so will have a tendency to disobey it.
Sure it gets attenuated, but NASA was able to receive the Voyager I signal from a distance of 11.5 billion miles. Of course, they were really looking, but we assume these hypothetical aliens are too. Voyager I has a primary transmitter that radiates a mere 22 watts. I’m betting the Earth radiates orders of magnitude more signal than that.
I’m currently reading Ann Patchett’s “Bel Canto”, a lovely little book about some 50 dignitaries of importance who were taken hostage by rebesl, and are left to cope in captivity during weeks of negotiations, all women having been released. Food is brought in, but they don’t know how to peel vegetables or boil water or wash out socks in a sink and are amazed that their dirty teacups don’t just magically find their way back to the kitchen.
I wonder who would be in charge of choosing the necessary “skillsets” to rebuild society? Coincidentally, why does today strike me as a particularly ironic day to contemplate this?
Our physical stuff already out in space isn’t a problem. It’s detectable, yes, but only if you already know exactly where to look. The surface of Mars, say, is really, really big, and interplanetary space is far bigger yet.
Given the scenario, we only need to hide the superficial evidence, that the Killer would pick up on during a brief flyby. That means two main threats: Radio waves and light pollution. The most realistic way to shut down both is to shut down all power plants for the five weeks of peak crisis. Some rogue transmitters might still have their own generators, but that’s going to seriously limit their available power. We’ll also want to try to keep secret the Killer’s exact orbital trajectory, so that rogue transmitters can’t beam directly at it. This won’t be entirely successful: Some people will be able both to detect it, and to do the math to predict its location as a function of time. But hopefully there will be little overlap between the set of people able to do that and the set of people who’d want to.
I wouldn’t trust the first aliens. Don’t try to fight the weapon. Don’t try to talk to the weapon. They give us no advice on how to hide. They’ve “warned” others but never said if their warnings did any good. Maybe the weapon is following them and they’re like the Silver Surfer leading Galactus to his next meal.