Ways the Earth could end but leave the planet itself intact.

[Cyrano]

Something like a loose virus would suffice, but I'm hoping for something more astronomical. I've looked a little into coronal mass ejections and gamma ray bursts, but it seems those would destroy the atmosphere. I want the world to exist in a a state where after it ends, it can still be populated by another species.

[thirdwind]

An asteroid impact would do the trick. A few number of smaller species would be able to survive and adapt after the impact.

[TPie]

How about the super volcano in Yellowstone National Park?

[A2theDre]

I'd go with super volcano. Except you'd be looking at hundreds of thousands of years before species started evolving.

[Carthonn]

Killer robots who eventually are unable to reach their oil cans.

[Banzai]

Airborn HIV would be a potential if you wanted to go down the vitus route.

Astronomically, an asteroid or meteorite would probably be the best bet, though a huge dust cloud would cause extensive climate change, which I'm not sure is what you mean by "intact". You could always have an extra-terestrial virus being delivered by a meteorite, sort of a la The Andromeda Strain.

Another option would be a neutron bomb, which would only affect biological material, though I'm not sure how easy that would be to work into your plot.

[Cogito]

A large enough matter-antimatter explosion well above the Earth's atmosphere would sterilize the planet with gamma radiation. You might need several such explosions to sterilize the entire surface, because the planet itself would absorb a lot of the radiation, so life could remain on the far side. Some organisms might still survive the irradiation, but the disruption of the ecosystem would probably kill most of the them. Your planet would be as nearly lifeless as a viable world for life to develop can possibly become.

The explosions would probably have to be the result of a mutually assured destruction scenario.

[B-Gas]

What kind of cataclysm are we talking here? Are the plants still around? Animals? Sea life? Bacteria? Micro-organisms that survive deep in the earth's core?

There's a huge amount of variation between different apocalypses. Some say that humans dying out would qualify, others would say that every strain of life would have to be eradicated. What are you aiming for?

[Cogito]

Micro-organisms that survive deep in the earth's core?Improbable at those temperatures and pressures. In any event, it would not be carbon-based life as we know it.

The more specific you get, the lower the probability of total extinction. For example, a virus that selectively kills humans is bound to leave survivors. Some would escape infection, and some would likely have a natural resistance/immunity.

[mammamaia]

fyi, the 'Earth' IS the 'planet'!... so your thread title/premise is oxymoronic...

[Cyrano]

I'm looking for something that could wipe out all life on a planet, but allow an outsider such as an astronaut to return days later, land, and realize everybody is dead.

[Cogito]

All life? In a matter of days? And yet the lithsphere, hydrosphere, and atmosphere are intact?

Gonna be a hard sell.

[Cyrano]

My plan was to have the main character abducted to another planet from Earth and told it was destroyed via [plot device here]. The character believes his abductors for a while, until he notices a suspiciously large amount of men and resources shipped to the supposedly void-of-life Earth. He stows away, and finds out that the civilization of his abductors is invading and enslaving the population of Earth.

So, it would be alright if the manner Earth is "destroyed" in seems a bit off. In fact, it may even be better that way.

[arron89]

Does it need to be explained? I guess that's a question more of genre than of the story you want to tell, but yeah...you don't necessarily need to spell out what has happened to make it work. Consider Time of the Wolf or The Road - both manage to convey the idea of apocalyptic/post-apocalyptic settings without explicitly naming or describing the apocalyptic event itself. Just assert the fact - all life on Earth has ended in the past day or two - and go from there.

That said, good luck getting that to fly with the hard sci-fi readers...

[A2theDre]

I thought you wanted to destroy life on earth. That means no population for slavery. You need to be clearer.

If it's an alien technology that is going to destroy life, you could have anything. You could have them shift the planet 0.1AU away from the sun, which I think would be far enough away for everything to freeze and die. Not sure how long that would take though...

[B-Gas]

Improbable at those temperatures and pressures. In any event, it would not be carbon-based life as we know it.

Micro-organisms exist everywhere in and on our planet. They've found them in ice bores, in core drills, in petroleum. There's one called a rotifer that can collapse its internal system and go dormant for decades. In this dormant state, they could be burned in magma, blasted with more radiation than a nuke would produce and then snap-frozen, and they'll still get back up when they've thawed out or moistened up on a temperate food source.

Anyway, if it's alien tech, then possibly just blanking the sun out for a couple days to kill off life and freeze the atmosphere. Won't get rid of microlife- nothing will, as long as earth has a molten core- but it'll get rid of almost everything else. Not that the atmosphere will be breathable until it melts again, and it won't have the same stuff in it anymore- it probably won't be breathable.

[A2theDre]

Ummm, they've only managed to dig 12km into the crust. So there's no proof of micro organisms existing in our planet. The pressures in the cores are much more than the pressures in the deepest oceans so I'd have to second Cogito on this one...

[Cogito]

At 5000-7000 degrees celsius, the organic chemicals necessary for carbon based life will not survive. Those are the temperatures at the core of the planet.

[mammamaia]

I'm looking for something that could wipe out all life on a planet, but allow an outsider such as an astronaut to return days later, land, and realize everybody is dead.


the civilization of his abductors is invading and enslaving the population of Earth.

as A2 noted, you're contradicting yourself... better get it clear in your head exactly what you want, before asking for advice on how to make it work...

as for what could end all life on earth, do you mean animal only, or plant life, as well?... the truth is, anything that could wipe out all animal life, would almost have to do the same to plant life, as well... and to do it in only a couple of days really limits your options... you'd have to dream up some as yet unheard of method, i think, as all scientifically possible ones would take much longer than 48 hours to end all life everywhere...

[Mark R]

My plan was to have the main character abducted to another planet from Earth and told it was destroyed via [plot device here]. The character believes his abductors for a while, until he notices a suspiciously large amount of men and resources shipped to the supposedly void-of-life Earth. He stows away, and finds out that the civilization of his abductors is invading and enslaving the population of Earth.

So, it would be alright if the manner Earth is "destroyed" in seems a bit off. In fact, it may even be better that way.

so you want a plausible reason that doesnt actually happen, but the aliens claim happens, to keep him quiet while they invade?

(others have made some of these suggestions)

asteroid would do it.

super volcano would have to be really massive, but could work.

wandering black hole passes through the solar system, close enough to earth to rip it up without actually destroying it (about as unlikely as it gets)

nuclear winter (maybe the lack of radiation is his first clue that something's up).

plague.. maybe the population aren't dead but there's no cure so they're quarantined? nobody can return (Except the aliens are).

[A2theDre]

Actually, something's just occurred to me. You could have the aliens set off every one of Earth's nukes, creating a nuclear winter. Then the aliens could take the astronaut away, and due to the near-lightspeed that they travel, 48 hours could pass for the astronaut, but it could be 100 years on Earth. Probably more than enough for everything to be wiped out and it to be almost habitable again.

Just a thought.

[zaphod]

maybe something nobody's though of yet like a "grey goo" scenario

or even that humans have merged themselves with computers until there is no need for physical bodies, then their sentience no longer driven by biological urges has no qualms in simply terminating itself because it has no existential purpose. That would be far out.

[talieseen]

You ever hear of Nemesis? It's supposedly a red dwarf star that is in binary synchronize orbit with our sun beyond the Oort Cloud, and passes by the Earth every 50 million years or so. As far as I know of there's not direct evidence to support it, just a theory based on some data about that sun that doesn't add up to what we do know. Well.. that and the projections show that the last time it would have showed up with Earth in range was around the last great extinction during the age of the dinosaurs.

EDIT: Resources online at a quick google..

http://en.wikipedia.org/wiki/Nemesis_(star)

http://www.space.com/scienceastronomy/solarsystem/nemesis_010320-1.html

Nothing currently states that Nemesis exists, but in a story.. eh *Shrugs* you could always say otherwise.

[bumboclaatjones]

dude, Super-Ebola. Kills people within like a week. Very contagious. Only one or two isolated outbreaks in quickly quarantined parts of Africa, but at least it's real, and kinda fits your scenario. Or does it? Aliens lying to a dude while they enslave mankind? why the hell would they lie to him instead of just enslave his ass to work in the Siberian Ice mines along with the rest of his pathetic species? That premise don't make no sense, but if you wanna kill off all the people on earth, then Super Ebola is the way to go.

[mammamaia]

you need to see this [i just caught it last night on the history channel]:

The Universe : 10 Ways to Destroy the Earth
http://www.history.com/content/universe/episode-archive

[CDRW]

dude, Super-Ebola. Kills people within like a week. Very contagious. Only one or two isolated outbreaks in quickly quarantined parts of Africa, but at least it's real, and kinda fits your scenario. Or does it? Aliens lying to a dude while they enslave mankind? why the hell would they lie to him instead of just enslave his ass to work in the Siberian Ice mines along with the rest of his pathetic species? That premise don't make no sense, but if you wanna kill off all the people on earth, then Super Ebola is the way to go.

Or you could have HIV mutate so that it's an airborn virus. There's a very few people with immunity, but they'd be so few and far between mankind wouldn't be able to recover. It takes longer to show symptoms and kill, but that ensures more people get infected before quarentiens are established.

[SilverWolf0101]

When you spoke about aliens enslaving a human and all that, strangely I was reminded of the movie "V" and that other one with the lizard people, who's title evades me at the moment.

There are many ways to destroy the earth though while leaving it intact, the thing is, if you want a quick death a virus seems to be the only way to go since the effects of super volcanos and such takes at least a good 48 hours or more to completely spread to it's full compacity.

Although I don't know how you want to work out your story, I have this strong urge to suggest the movie "Lost in Space" to you. Perhaps my reasoning is because of the father coming back "a few years later" to find his family dead and that one doctor the only survivor though evolved. Maybe there is some way you can use this idea to your advantage.

[BUDDY GORGEOUS]

How about something that destroys the way in which we have Oxygen?????????

[JoenSo]

dude, Super-Ebola. Kills people within like a week. Very contagious. Only one or two isolated outbreaks in quickly quarantined parts of Africa, but at least it's real, and kinda fits your scenario. Or does it? Aliens lying to a dude while they enslave mankind? why the hell would they lie to him instead of just enslave his ass to work in the Siberian Ice mines along with the rest of his pathetic species? That premise don't make no sense, but if you wanna kill off all the people on earth, then Super Ebola is the way to go.

The problem with ebola (in this context that is...) is that it's so lethal that it kills off those who are infected before they are able to spread the disease too much. Of course, if you have aliens involved I guess they could just sprinkle the whole planet with the ebola virus... Otherwise I'd go with a disease that have long incubation and that few people are immune to. Smallpox perhaps, they still have some specimens of it for research.

[NaCl]

Small pox (Variola Major) is a fragile virus that can only exist in human hosts. The most common variation kills around 35% of non-inoculated victims. Two variations (Flat Small Pox and Hemorrhagic Small Pox) constitute a very small percentage of outbreaks but are 98% lethal. It has an incubation period of 12 days to two weeks and is not contagious during that time. The disease then produces symptoms and contagious exposure for another two to three weeks, assuming the person lives that long.

The big problems for this disease, as a mechanism for world wide human elimination, are 1) that 65% of victims survive and become permanently immune, and 2) the virus can not survive in any other medium but human cells. Consequently, the Variola virus actually ends its own existence when it runs out of new humans to infect. I have done an enormous amount of research on this virus for a book I am currently writing. You'd be better off to postulate a multiple species virus like bird flu and mutate it into a new, uniformly lethal virus...maybe a hybrid between Bird Flu and one of the hemorrhagic viruses like Ebola, Congo-Crimean hemorrhagic fever or Rift Valley fever. Such a mutated virus could be transported by rodents, birds and mosquitoes so that it can continue to replicate and spread outside humans.

[JoenSo]

Small pox (Variola Major) is a fragile virus that can only exist in human hosts. The most common variation kills around 35% of non-inoculated victims. Two variations (Flat Small Pox and Hemorrhagic Small Pox) constitute a very small percentage of outbreaks but are 98% lethal. It has an incubation period of 12 days to two weeks and is not contagious during that time. The disease then produces symptoms and contagious exposure for another two to three weeks, assuming the person lives that long.

The big problems for this disease, as a mechanism for world wide human elimination, are 1) that 65% of victims survive and become permanently immune, and 2) the virus can not survive in any other medium but human cells. Consequently, the Variola virus actually ends its own existence when it runs out of new humans to infect. I have done an enormous amount of research on this virus for a book I am currently writing. You'd be better off to postulate a multiple species virus like bird flu and mutate it into a new, uniformly lethal virus...maybe a hybrid between Bird Flu and one of the hemorrhagic viruses like Ebola, Congo-Crimean hemorrhagic fever or Rift Valley fever. Such a mutated virus could be transported by rodents, birds and mosquitoes so that it can continue to replicate and spread outside humans.

Aaah, I see. I'm afraid my knowledge of diseases are limited to what I pick up from those of my friends that study biology... My thought with smallpox was that humanity would be very unprepared for an outbreak of a disease that supposedly have been completely eradicated. Of course, as you say, if a disease spreads through animals (or better: air) it will be much more effective. Though, if you want to get rid of everyone a disease is probably not a good way to go. It seems like there's always someone who's immune...

Oh, I just remembered a not-quite-so-plausible scenario: I've read that when the first test of a nuclear bomb took place they weren't exactly sure what capacity the bomb would have. Some people thought it would be less devastating than it was, and apparently someone feared that it might somehow ignite the oxygen in the athmosphere, causing a disastrous chain-effect. Don't quote me on that since I read it somewhere on wikipedia ages ago, but if you're an alien you just might be able to fool an astronaut with that scenario...

[SilverWolf0101]

They'll be a new series coming out on syfy, about how the world will end in 2012 without the earth being torn to shreds. I didn't catch all the details but I seen the add and it reminded me about your thread. Check it out, and hope it helps.

[Cyrano]

Just thought that I'd say I've adapted the plot so that I no longer need the planet to appear completely intact. Thank you all for your ideas.

[InkDream]

You're talking about the end of humanity then, not the end of the world or all life on Earth. Realistically mankind is a hearty species; we adapt to new environments and our bodies adapt to and learn to fight off disease (those who survive). Widespread disease would cripple us as a species but not everyone would die. Look at historical examples like the plague and even Ebola. People survive. Nuclear winter (or a gigantic asteroid) could wipe us all out but it would be everything, not just humans.

In other words, short of an apocalyptic type alien invasion that destroys all human life, I can't think of anything that would kill off mankind but leave other things living.

[Neo]

How glad am I that I came across this thread!

I'm planning a story where a severely mutated form of HIV becomes airborne and wipes the population out in a week, leaving a few naturally immune people to try and survive together.

Can anyone elaborate some points to consider in my scenario? I have a pretty good idea how to "sell" the idea that the whole planet gets infected in the space of a few days, a narrative device where the spread is communicated in a similar way to that used in The Stand - he spread this to her, and she spread it to them, and they spread it this way...etc. etc...

[mammamaia]

Can anyone elaborate some points to consider in my scenario?

meaning what?... do you want others to create a storyline/plot for you, or what?...

[bluebell80]

Neo...aside from the basics, no utilities, no food, and in four days of no one taking care of them--all nuclear power plants would begin to melt down... You can have your survivors encounter a great many things in their struggle to survive. No one here can make a plot for you, that is part of being a writer...thinking of the "what if" scenarios.

[crashbang]

i got one for you. the neutron bomb.

theres stuff on wiki that could help you, but basically, the neutron bomb sacrifices sheer destructive power for powerful, penetrating radiation. although most neutron bombs nowadays still have a massive explosive yield, back in the day they wewre seen as a way to stop a russian tank blitz in the cold war - wipe out the men in their tanks, leave europe intact. of course exactly what the plan for the people living in europe was, im not sure. ive pretty much just looked this up.

the jist is that someone insane enough with the rescources could probably wipe out most of the worlds human population with some well placed neutron bombs, while still leaving a significant portion of the nature of the planet intact.

in theory.

[Cyrano]

Can anyone elaborate some points to consider in my scenario? I have a pretty good idea how to "sell" the idea that the whole planet gets infected in the space of a few days, a narrative device where the spread is communicated in a similar way to that used in The Stand - he spread this to her, and she spread it to them, and they spread it this way...etc. etc...

The only thing that bugs me is how the immune people are going to locate each other. I don't know how many survivors you plan to have, but I can imagine people wandering around for a very long time before coming in contact with any other survivors.

[mammamaia]

give them esp?

[talieseen]

How glad am I that I came across this thread!

I'm planning a story where a severely mutated form of HIV becomes airborne and wipes the population out in a week, leaving a few naturally immune people to try and survive together.

Can anyone elaborate some points to consider in my scenario? I have a pretty good idea how to "sell" the idea that the whole planet gets infected in the space of a few days, a narrative device where the spread is communicated in a similar way to that used in The Stand - he spread this to her, and she spread it to them, and they spread it this way...etc. etc...


Highlight some points... what exactly? I can write out my immediate thoughts on it though. 1) The reason why there is very little fear of the HIV retrovirus ever becoming airborne is due to the fact that for a virus to become airborne it must lose a majority of it's DNA (RNA in the case of retroviruses) to become light enough to float. In the case of HIV it has been speculated that in order to become airborne it would have to lose so much RNA that it would become a weaker version of the common cold (also a retrovirus). 2) A natural immunity to a virus is very likely, there are even people who have chronic HIV due to the fact that their bodies can keep it check, though not kill it off. That is what natural immunity usually means, you are still infected but to such a low degree you have very little symptoms from it. 3) Keep in mind that HIV doesn't kill the person, it only allows another virus to do the job of killing the subject. So the if you wanted to do HIV there would have to be a second infection that would be so widespread as to help cause the collapse of civilization. 4) HIV takes years to turn into full blown AIDS, between 2-12 depending on circumstances and health of the subject. So, it wouldn't be something that would have a sudden impact.

Given this, I would personally say that the idea of an airborne version of HIV killing the majority of people is not very likely at all. In order to make it more effective it would have to have extra sequences added to its RNA base, which would make it even less likely to be airborne. However.. there are a LARGE number of viruses that are far more deadly and likely to be easily widespread, most are already airborne or very easily could be. Hemorragic (spelling is wrong) Fever for one, or Encephilitis Letharigaca (spelling also off) for another. The first is similar to what you would see if you ever watched the movie Outbreak. The second is a form of encephilitis that causes the infected person to become disoriented and enter a deep comatose state and has no known cure.

[ToxicWaste]

The problem with neutron bombs is that they are only 1/10th the yield of their conventional nuclear cousins. That being said they are still quite dangerous to anyone close enough to be struck by their fast neutrons. These bombs can deliver a massive radiation dose (80 gray) almost instantaneously to the occupants of a Russian tank (i.e. T-72, T-80, T-55) despite the radiation shielding at about a kilometer. So air burst detonation over a tank formation would completely "neutralize" it.

That being said they hardly "kill people and leave the buildings intact." Only 30% of a neutron bombs radiation is emitted as neutrons.

I'd stay away from the concept of nuclear winter, as it has mostly been disproven as hype. The month with the largest decline in temperature would be July which would have a temperature of 50 degrees Fahrenheit vs its standard 70 degrees.

Furthermore fallout from a bomb is not a long lasting danger. A "hot zone" that has radiation levels at 1000 R/h (it takes 350-500 Röntgens in an hour to kill a human) will have decayed down to 100 R/h after 7 hours and 10 R/h after 48 hours.