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33

If I remember my sci-fi correctly, I think one of the more accepted methods of doing this is using the 'hide a tree in a forest method'. In other words, just hide the escape pod within a meteor shower, and use atypical methods, such as deploying the equivalent of a BASE parachute at the last possible moment, or something of that nature.


26

The humans are toast (well, medium rare anyway). Short version : ten degrees Celsius should do it, twenty would be more than enough. Luckily for us, their ovens are really slow and the Earth heats up really slowly (a few degrees celcius every year) Which, I assume would give use enough time to react to the change in temperature and allow us to start ...


24

Putting aside whether the "escape pod" has enough delta-V to break orbit, depending where they reenter it's very possible. I'd put the mother craft in a polar orbit, so they can reenter over the extreme southern Pacific, near the "pole of inaccessibility", and pass over Antarctica during the hottest part of the trip, then land in the extreme southern ...


22

I'm going to respond to this with a framing challenge, because as it stands I think you're asking the wrong question. The issue is that the modern industrial world is a product of population DENSITY rather than total population. This may seem semantic but in a post-apocalyptic environment it's very meaningful. Modern industrialism depends on and benefits ...


15

Is the ship under observation for routine traffic control or other purposes? If people on Earth are serious about watching, and if they are already observing the ship, breaking contact will be difficult. Aircraft like the Cobra Ball or Cobra Eye might be deployed to fill gaps in the ground coverage. If it is routine, Earth might rely on secondary radar and ...


14

A metallic "glass" would be an amorphous metal or alloy. This material is commercially available in ribbon form (only, last time I checked), and is far from transparent (it looks like solder ribbon or metallic tape). It has most of the same properties as the metal it's made of, except that it has no crystal structure (this affects bending strength, for ...


13

Unshielded humans will expire above 40 C Well-prepared humans should be able to hang on to 1000 C and more for some time. Due to our temperature management, humans can withstand temperatures above 100C for hours, and between 40 and 50C for days. However, all natural temperature management depends on evaporation and works only in low humidity. In high ...


11

Actually, it is possible and people do it. Tidal turbines generate power off of the tide rising and falling. This is indirectly generating power off of the Earth's rotation, and here is a diagram explaining why. The earth has such a massive amount of kinetic energy that tapping into it a little is not noticed, but building thousands of tidal turbines ...


10

Generally speaking, metallic glass (in terms of what you can see through) does not exist because metals have non localized electrons. This means that when light or electrons hit metal, they want to be bounced around or conducted instead of passing through. Instead there are real-life materials which are actually very hard, clear ceramics that can offer ...


9

It's going to be very difficult to remain undetected. In fact, it's possible to see the dragon space capsule, which a reasonable size for the escape capsule, with naked eyes alone. Amateur satellite trackers could very well see the separation or the fact that there are two objects where there is supposed to be one and report it on twitter. Military/traffic ...


9

Depends a lot on how humans prepare. Without humanity adapting, with the above scenario you'll probably collapse society in 5 years and make us extinct in 10. However, just heating up won't hurt well-prepared humans. For example, dig a few hundred meters into a mountain, and you won't even notice the external heating. Easiest method for humanity to create ...


8

Europa has a surface gravity of about $13\%$ of Earth's. This means the force (weight) of the water in Europa's oceans is proportionately less than on Earth. If you divide Earth's deepest ocean depth (about $11\,km$) by $0.13$ you get a "Europa equivalent depth" of about $85\,km$, which is actually the ballpark for Europa's deepest ocean depth estimates. ...


8

I've used a personal analogy for this, which I call "The brake pad problem." I estimate (without any serious research) that maybe a few hundred people around the world really know what it takes to manufacture an automobile brake pad. If you kill them all off, we're in serious trouble at least until a new process (or a reconstruction of the original) can be ...


8

As I think through this I face a few issues that constitute a Frame Challenge. No prison is inescapable with the right amount of help. "No contact" might need definition. Unless you're planning to either build an entire self-sufficient space station (outside our current tech) or drop him on Mars (kinda still outside our tech if you can't go near him for 8K ...


7

TL;DR: a rocket that does a short boost, coasts for 2 weeks, and does another short boost is much more efficient than one that runs its engine for the entire journey. It can make do with a much less powerful engine, or vastly less fuel. It also makes provision of artificial gravity simpler, and relaxes debris shielding requirements. Its higher thrust also ...


6

In addition to the fact that it will almost certainly be seen in flight there's the fire of re-entry that you can't hope to conceal even if you put stealth systems on it--it's not the capsule that you're seeing, but the plasma it leaves behind. This will be obvious to the naked eye so the only way you can hope to get down unseen is to ensure there are no ...


6

Mental retardation is (or was; an archaic term) a developmental disability. You are born that way. If you lose brain power (executive function / intelligence etc) that is either dementia or encephalopathy. Dementia is from things like Alzheimers disease, multiple strokes, long alcohol use or the like. Demented people are wide awake and in the world - "a ...


5

Wave them hands! You had me at gunfight in the factory, using sheets of glass for cover. Awesome. Make your metallic glass be what your story needs it to be for the story as regards bulletproofness and other properties. It is not so farfetched. Do it up! I like a closing scene where the protagonist enters some stuff into his phone then curls up and ...


5

Cell death occurs at 65 degrees Celcius or 149 F. I am informed that is pretty much universal for cellular organisms on our planet, or at least not those living on undersea vents or boiling mud. As noted in a previous answer, human beings are adept at creating temperature controlled enclosures and depending on available power some could survive ...


5

Doable, yes. Feasible, no. This shouldn't surprise you, because if it was feasible, presumably Elon Musk would have done it. This sounds really weird, but as it happens, there's a way to gain kinetic energy, which can then presumably be transferred to thermal/electric energy, which functions as a result of using the Earth's movement and slows it down. And ...


4

Rocks Simply put you throw rocks at stuff you don't like. Fortunately our solar system is full of rocks just waiting around doing nothing, so we just grab a few (OK, more than a few) and direct them gently at the source of the problems (any inhabitable place) and wait for nature (and gravity) to takes it course. In the due course of time you can not only ...


3

I am going to give you something of a frame challenge here - while you generally want to keep the properties of the glass realistic, don't forget to let your factory and production process of the glasses seem somewhat real too. I'm not sure if a lot of readers will care whether your characters are fighting among metallic glass, aluminium oxide sheets, or ...


3

One thing about human space flight in the present day is that Mission Control monitors everything and I do mean that. If you ever watched the film "Apollo 13" you'll recall the scene where Mission Control reports about some minor spike in Jim Lovell's vital signs, which is the straw that breaks Lovell's cabin fever, and he rips of the signal monitors ("I ...


3

Short answer Your craft can't even land on Earth, and the defectors explode on re-entry, or they get stuck in space forever and starve to death. If you suspend reality, the answer you're looking for is: Merely by initiating an unannounced landing you already have a headstart. I tried like to hell to find astronaut recovery times, but I couldn't track any ...


3

Chicken and Egg The material is theoretically understood by everyone, and its creation involves something akin to a fusion reactor, which can be done efficiently if you already have enough of the material, but there are such small amounts present in stolen items that this is not practical. (Perhaps it needs to be in the form of giant single crystals/pieces/...


3

No. "Present age" technology level implies batteries that operate from chemical reactions, and there just isn't room to increase energy density by more than one or two orders of magnitude. Burning pure hydrogen produces 120 or so megajoules per kg, which is about 33kWh/kg. If you include the mass of the oxygen needed to combine with it, that drops to about ...


3

How to reduce things to rubble easily Relativistic kill missiles are your best bet for thoroughly destroying inhabitable places in the solar system (which is technically every one of the nine planets and most of the dwarf planets, given enough technology) is to use relativistic kill missiles; the aliens could just send kilometer long projectiles moving at a ...


3

A small stream of strangelets in a series of flyby trajectories around the sun will do the trick. As long as the sun is not touched, it is safe. Everything else becomes lethal to the touch. Since the ΔV from even Mercury to the Sun is immorally huge, the sun should be safe. Add to that, solar wind pushes stuff away from it... Over millenia other stars ...


3

This is both doable and feasible, even with near-future technology. As described in David Brin's short story "Tank Farm Dynamo" (1983), you can let an orbiting satellite have a large wire loop that interacts with the Earth's magnetic field to produce electricity. This slows down the satellite, making its orbit decline, but it will also slow down the Earth's ...


3

This may just be possible Let's check the number you're looking at. A human needs about 2,000 calories a day, but without movement we can decrease that number to maybe 1,500, or even less. Multiply that by 365.25 days per solar year, for 8000 years and you end up with 1.789 x 10^13 joules of energy. Or, to put it in better numbers, 1/4 of the total energy ...


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