Hot answers tagged

110

The maximum height a mountain can have on Earth is a tad more than what Mount Everest is high. This is due to the fact that when you increase the height of the structure, you are also increasing the load. After a certain point you will be adding too much weight for what the material can sustain, and the entire structure will crumble on itself. The potential ...


106

Not with the time constraint given. Let's start with the most destructive thing we've got: nukes. There are about 15,000 nukes worldwide, of varying yields. Sources: World Nuclear Weapon Stockpile, Plougshares Fund, 2018 Federation of American Scientists, 2018 Assuming an average yield of 200 kilotons, which is what most US nukes have, we could assemble ...


81

As a native I'm definitely biased here, but Ireland is actually a pretty good bet. Especially towards the West, Ireland has actually seen a decline in rural population. You can genuinely walk for miles and see no signs of civilisation. I'm talking even the grass has no footprints. Predators? Ha! St Patrick took care of our snakes, and our beloved English ...


79

You've already accepted an answer, but aside from the structural issues (and the sheer mindboggling amount of energy it would take to pump all that water up that high), there's another misunderstanding: allow a train running on a train track going up the cone to escape earth's orbit? Getting into orbit isn't simply a matter of getting up really high. ...


77

Even the satellites and every sensors on Earth were returned to that exact moment and this only affects the entire region of space up to orbit of moon (...) Everything above the Moon will seem to have changed position instantaneously in a very weird manner. All the signals picked up by the Deep Space Network will be coming from the wrong places. Solstices ...


65

The problem your going to have in any open sky area however, is the familiarity of the moon and constellations - a dead giveaway that your still on earth. To that end, I'd suggest the best place for this scenario would be a large underground cave system, like Reed Flute cave in China:


63

No. Most of the preceding responses have overlooked one relatively-recently identified home for life on the planet; within the crust itself. Researchers have found bacteria up to 4 kilometers down in continental crust and 2 km beneath oceanic crust. Recent estimates are that up to 70% of the microbial life on the planet is, in fact, in the deep biosphere. ...


59

This place cannot have any obvious life forms. Nothing too complex (Small microbial creatures are fine) No humans for at least a few hundred miles, and no signs of their presence. Must be somewhat hostile to human life Cannot be underwater Inland Antarctica seems to satisfy all the above: Doesn't have obvious life form, not animal nor vegetal,...


51

Everything Dies The combination of mass and velocity is inescapable. The follow-on asteroids don't matter. The initial impact will do the trick. Half the mass of the moon is approximately 36 sextillion kg. So the energy carried by the impactor is $$ \frac{1}{2} \times 3.6 \times 10^{22} kg \times (0.05c)^2 = 4.13 \times 10^{36} joules $$ While the ...


46

You have problems, and it isn't food Food is easy. The ocean is full of fish. So long as your story places the aircraft carriers in the right place, food is irrelevant. Your problem is nuclear fuel. Those aircraft carriers are big, sealed, bathtubs. Without ventilation, the CO2 resulting just from human breathing would slowly make the lower decks ...


44

•98% of all the landmass is wasteland/desert •The two poles are some big chunks of ice, each covering about 20% of earths area This is rather confusing. Yes, I get that there are also cold deserts, but next to the glacier there will be the melting zone, where the bonanza of water will inevitably favor life. •There are only two climate zones, hot ...


43

Two places come to mind immediately; The soda lakes of Tanzania The soda lakes of Tanzania are quite uncomfortable places for humans to be, and ultimately they fill the brief of 'somewhat' hostile to human life. But, they also look the part when you think of an alien landscape. These lakes of soda ash are pink in colour and extremely alkaline, meaning that ...


38

GPS satellites - almost all satellites, really - need to have the capacity to be remotely "disabled" as part of their end-of-life protocol. Satellites degrade over time like all things do (especially things exposed to the orbital environment) and they're also steadily rendered obsolete. To avoid old satellites cluttering up the most useful orbits and ...


29

There's a lot that goes into answering this, and the answer could turn into either yes or no depending on what assumptions and trade-offs you make. Firstly, nuclear carriers have an operational lifetime of 50 years, and get a overhaul and refueling at the 25 year mark. This is assuming that the carrier is actively being used for military purposes, if you'...


29

Add Danakil in Ethiopia .. Volcanic activity and solved salts give multicolored water that's borderline acid and thus dead - and the colors give a nice flavor even combined with a natural azure sky Edit: Not even microbes were found in the ponds ... thus they not only appear foreign and dead .. they are deadly, poisonous, acidic


27

Earth is gone. The Moon is gone. Mars gets nuked. The entire Solar System becomes hotter than Mercury for a couple days. The Sun will appear to glow up to 12,000 times brighter. The Solar System will be forever scarred. As jdunlop's answer says very succinctly, 'everything dies'. But let me tell you precisely how dead everything is. The asteroid delivers ...


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 ...


26

Oh, the pain... Bedrock is your first problem. You're not building an itsy-bitsy building like the Burj Khalifa or the Tower of Pisa, your'e building the building, the biggest, honkingest, Oorah-est building on the planet. And you're guaranteed to crack the foundation if we don't go all the way down to bedrock, grind the bedrock flat, drill in a bazillion ...


25

I'd suggest Hawaii. No large predators - biggest things are wild pigs, which generally avoid humans Fresh water, both from rainfall and from mountain streams Plenty of edible plants which grow year-round Weather is warm, but not too hot - shorts and a t-shirt are fine, but cold isn't a problem if you do outgrow your clothes There's a large enough wilderness ...


25

Use a Human Terrarium The single most definitive piece of evidence that you may be somewhere alien is... the aliens. Instead of putting them in an open field on some plant designed to look alien that just so happens to be able support human life with 1G of gravity, 1 yellow star, and familiar constellations, put them in a giant indoor terrarium. Add ...


24

Even if you stick to daytime to avoid the issues raised in the comments, there are still some things that would lead the astronauts to think they're on earth - the sun being the right colour/distance, the temperature being in earth ranges, the fact that they can breathe the air, the exactly-1g gravity, etc. Indeed, "we're on earth somewhere" requires a far ...


24

I would say specifically the dry valleys of Antarctica rather than the ice sheet. We’re used to the idea that there are ice sheets on Earth, but a valley with no ice or visible life, and very cold temperatures, looks very alien.


21

in my opinion tropical jungle/forest island with lagoon (its quite common not rare) prefferably big (high chance to be because of current global warming drown the smaller one). you wont encounter winter you wont get frostbite or chance of death from the extreme cold (unless you are near a hill or mountain site of the island which is colder) so no need for ...


21

Any Temperate Rainforest As a previous answer says, Ireland would be a great place, but there are several other similar areas in the world: northern Spain, eastern Black Sea, East Asia, the Pacific Northwest, and southwest South America all have one thing in common: they are temperate rainforests. Ample Food Tropical rainforests, which many other people ...


20

Water and Food: These are easy. Spend \$60 on a Costco membership and you can get a pallet of spring water for \$360. That's enough water for you and your wife for 8 months if you use it for nothing but drinking. Then stock up on non-perishable foods that don't need to be cooked. Beans, canned fish (in oil for extra calories), nut butters, crackers, and ...


20

"It's the smell!" -- Smith I think the easiest answer is that there is something in Earth's biology that disagrees with them... something that can be "managed" with continuous medical intervention, but would be really annoying for them to try to settle permanently without completely terraforming the planet. Imagine, for example, that 99% of the aliens ...


19

You have several concerns and the limiting factor here is money. We'll have to assume you're a handy person and can do your own installations. 1. Security. You want to buy a security screen door for each exterior door of the house (or at least one for the front and one for the rear and you can seal off side doors). These will run you about $300 each, but ...


19

5% of lightspeed is insanely fast for an asteroid. Earth is gone. It doesn't matter where that giant asteroid hits. Luna is gone. Some of the combined mass might form a new belt, but much will be "shotgunned" throughout the solar system. Stations close to Earth or the Moon will almost certainly be hit by fragments.


18

You're positing a world that has no surface plants. That's... implausible. There are plants out there that can manage climatic extremes far worse than anything humans could live through. Plants actively thrive in concentrations of CO2 that humans would find lethal. You might easily have a massive die-off as climate change modified local conditions, but ...


18

Well, the one thing that life needs on Earth (and pretty much anywhere else depending on how extreme your xenobiology is) is water. Now, we're not trying to boil the ocean here but... No wait. That's exactly what we need to do. Let's start with how much water that is to boil. We're talking about 1.26 x 1021 litres of the stuff. That's a lot and is going ...


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