Earth (or another species' homeworld) has fallen victim to some disaster and is no longer inhabitable. But fear not, we managed to get some people off before it was too late. The actual means of escape will usually be some form of The Ark
For some reason this seems to be the sole reason for interstellar colonization in most "mainstream" sci-fi.
A common variant is "Earthless circumsolar civilization fiction
;" Earth has become inherently hostile to a Humanity that lacks
interstellar travel, resulting in the creation of a Die or Fly
Always results in a case of Earth That Was
, though in some cases of that trope the space colonies existed before the disaster. For when the survivors already happened to be in space for unrelated reasons, see But What About The Astronauts?
Anime and Manga
- Eureka Seven takes place over 10,000 years after Mankind was forced to leave the Earth due to an unintentionally harmful alien life. Somewhere along the line, all of Humanity found a new place to settle down, completely forgetting and/or unaware that they just went back to Earth and live on a new surface that was created by the aliens. The real, perfectly inhabitable Earth, lay below the surface.
- Dragon Ball Z: When the Namekian homeworld is set to explode by one of Frieza's attacks, a wish is made on the Dragon Balls to save their lives by evacuating all the Namekians to Earth. Then they promptly had the dragon make them a new one and had themselves beamed there.
- In Dragon Ball GT, when Earth is set to explode by the effect of the Black Star Dragon Balls, everyone is evacuated to the nearby planet Plant, which had just been placed on Earth's orbit.
- Suisei no Gargantia takes place hundreds or thousands of years after humanity evacuated Earth to escape an impending Ice Age. As it turns out, Earth has since thawed and is habitable once more, but most of humanity has forgotten where it is. It is instead populated by survivors of those humans who were left behind.
- Cowboy Bebop: The Hyperspace Gate explosion fifty years prior to the events of the series blew the moon to pieces, and the chunks are still falling on Earth about as regularly as rain. It's basically a giant slum, and the most well-developed planet is Mars.
- Macross: About 3/4 of the way through the series, after fighting a losing battle against the giant alien Zentraedi, the vastly outnumbered humans witness the near-total sterilization of the surface of Earth. Unlike most examples, some of the survivors resettle the Earth and slowly rehabilitate it.
- The Authority do this in one arc, evacuating the planet's entire population so as to cause less collateral damage when fighting a superpowered villain.
- Project Sunflower: An evacuation is attempted after a space-borne monstrosity dubbed the Black Tide, which is using nanotechnology to remake the planet into something hideously alien, crashes on Earth. They use two methods: massive space arks (which are subsequently sabotaged by the "Earth-First" terrorist organization, which is bent on forcing the government to continue fighting rather than evacuate, which they call the coward's way out), and Project Harmonics, intended to find a suitable alternate dimension that humanity can move to. Instead, they wind up finding new allies who, after two separate attempts, succeed in destroying the Black Tide and making it unnecessary to evacuate.
- Deconstructed and averted in The Conversion Bureau: The Other Side of the Spectrum, however. It's made abundantly clear at least three times (twice in the main story, once in Calm) that it's just not going to work. Mostly because of the radiation in space, limited resources (both for making the ship and helping the crew survive), lack of habitable planets, and, as Crowe pointed out, the few colonists that could escape would be nowhere near a match for Celestia if she eventually found them.
- WALL•E: Humanity relocates to ships like the Axiom for 700 years.
- In Titan A.E., the alien Drej vaporize Earth in the opening sequence while refugee ships try to escape.
- In Battle for Terra, Earth, Mars and Venus have all been blown up, so humans go to the eponymous planet to find a new home.
- Oblivion has humanity attempting to escape a ruined Earth that has been wrecked during an Alien Invasion war, settling a new colony on Titan. Of course, this is a big damn lie, but saying any further details is a massive spoiler.
- In the live-action Transformers film Cybertron was destroyed in the Autobot/Decepticon war and they search for the Allspark in order to rebuild it.
- Star Trek:
- In the 2009 Star Trek movie, the planet Vulcan kicks the bucket, and at the end of the move, Spock Prime considers it his mission to help the remaining Vulcans establishing a new home world.
- Star Trek Into Darkness reveals that New Vulcan has been established.
- In Jason X, humanity left Earth due to pollution and has resettled on a new planet called Earth Two.
- At the start of Man of Steel, Krypton is about to implode. Jor-El's pleas to evacuate Kryptonians falls on deaf ears, as no one believes that their planet is dying. General Zod believes Jor-El, but only wants to save the elite bloodlines. Jor-El, instead, decides to only save his infant son.
- Mission to Mars shows a holographic recording of Martians evacuating their planet for a distant galaxy en masse after a meteor strike renders the planet lifeless, except for a lone ship heading for Earth to seed it with life.
- Earth is polluted and overpopulated in Red Planet. Humanity's only hope is to terraform Mars and re-settle everybody there. The mission is sent to determine why terraforming is failing. At the end, it's implied that the terraforming and re-settlement project will be scrapped in an attempt to replenish the dwindling levels of oxygen on Earth using the oxygen-producing bugs found on Mars.
- After Earth, as the name implies, takes place in the distant future after humanity evacuated the now deadly Earth.
Live Action TV
- In Last and First Men the Fifth Men migrate to Venus when the Moon (destabilized millions of years earlier in the Martian/Second Men war) starts to crash into the Earth. And the eighth men design the ninth to colonize Neptune when the sun expands to cover the Inner System. But eventually the sun goes nova too quickly for the Eighteenth Men to devise a means of escaping to another system, though they do manage to send out "seeds" of life that might eventually evolve into new humans.
- In the "Homecoming Saga", a series of 5 novels by Orson Scott Card, the Earth was rendered uninhabitable by human wars, and mankind departed for Harmony, as well as at least forty other planets.
- In Walter Jon Williams' Aristoi, Earth was destroyed by Grey Goo, leading to the reorganization of society into essentially a confederation of feudal states, with each state's leader (the Aristoi in question) being the only ones allowed to use nanotechnology freely.
- Arthur C. Clarke's Rescue Party has aliens coming to Earth in order to try saving at least a few humans before the Sun goes nova. In the end, it turns out the humans built a fleet and left already.
- Robert Sheckley has a story with an amnesiac human waking up on a starship, apparently the last survivor after a nova. The ending reveals he serves as a Neuro-Vault for all of humanity.
- Gianni Rodari has two short stories about aliens from a threatened planet settling on Earth.
- Isaac Asimov's The Currents of Space end with a planet (not Earth) being evacuated - its sun is about to go nova.
- In the Isaac Asimov book Robots and Empire which links his Robots series to the Foundation series, a robot causes/allows a radioactive explosion which will slowly poison Earth, forcing the population to expand out into space.
- Happens twice in the Noon Universe:
- The premise of Space Mowgli is that Terrans intend to evacuate the Human Aliens of the planet Panta, whose sun is about to explode, to the planet Ark (named after Noah's Ark).
- In Beetle in the Anthill, the scientists speculate that the entire population of Hope (the planet Abalkin explores in the flashbacks) was evacuated to another (unknown) planet by the Wanderers.
- The Insects From Shaggai (AKA Shan) in Ramsey Campbell's Cthulhu Mythos stories. When their home planet was destroyed by a Mythos abomination, some of them fled to a succession of other planets, finally ending up on Earth.
- In the backstory to the Gor series the Kurii destroyed their homeworld in intercine battles, so they went looking for a new home and found Earth & Gor. The Priest-Kings have waged a war against the Kurii to keep them out for millenia, all unseen by most humans.
- The Yuuzhan Vong of the New Jedi Order series underwent a home galaxy evacuation, after massive wars of conquest and then internicine wars they started devastated so much of it that it was rendered incapable of sustaining their civilization (their actual homeworld was destroyed first, and it's speculated, though not fully confirmed, that they were the ones who did it). After travelling through the intergalactic void for milennia, they finally found the Star Wars galaxy - and decided to take over.
- In The Hitchhiker's Guide to the Galaxy the colonists aboard the Golgafrincham B Ark were tricked into believing that they were part of one of these, though everyone had heard a different story of what doom was facing Golgafrincha, moon crashing into the planet, planet crashing into the sun, ravenous mutant star goat, etc. The reality was that the B Ark was composed of the "useless" third of the population (telephone sanitizers, hairdressers, middle managers...) and the rest of the planet was getting rid of them. Ironically, the remaining two-thirds were then wiped out by a plague caused by an unsanitized telephone.
- In For Your Safety, the Earth is forcibly evacuated by the Groupmind, a distributed AI that determines that the only way to reverse centuries of environmental damage is remove all the humans and move them to a giant Ring World Planet style space station orbiting the Earth.
- Somewhat inverted in Battlestar Galactica (Classic) and Battlestar Galactica (Reimagined), the twelve colonies of Kobol are being evacuated and searching for Earth, which is the "lost" thirteenth colony.
- A surprisingly consistent point of future history in Doctor Who foretells the mass evacuation of Earth around the thirtieth century, to avoid solar flares. The Eleventh meets the Starship UK in "The Beast Below", but it comes up in other episodes as well. In addition the fourth Doctor encounters a wheel-type space station full of sleepers in "The Ark in Space", which is set 20,000 years in the future, implying that it happens more than once.
- The National Geographic special Evacuation Earth has as its premise a wayward neutron star heading towards Earth and attempts to build a Generation Ship to take 250,000 people to Bernard's Star.
- In Defiance the Votan Collective came to Earth when a supernova destroyed their home system. Their sublight ships departed 5000 years ago. They knew Earth was habitable but thought it lacked intelligent life due to the lack of radio signals from it. They were really surprised to be proven wrong when they arrived in 2013.
- On the Planet of the Week in the Stargate SG-1 episode "Lifeboat" SG-1 finds a crashed Sleeper Starship built by a human society called the Talthuns, who had evacuated as many people as possible before their planet was destroyed by a coronal mass ejection caused by a "dark star".
- In the Babylon 5 episode "The Deconstruction of Falling Stars", which flashes forward to different eras of humanity's future after the show's time frame, it is shown that humans evacuate Earth one million years in the future, before an impending mysterious artificially-induced nova explosion of Sol.
- Star Trek: The Original Series episode "The Empath". The star of the Minarva system is about to go nova. A group of highly advanced aliens known as the Vians can save the population of only one of the planets in the system. They decide to determine which planet's population will be saved by putting a member of each population through a Secret Test.
- In The Event, it's eventually revealed that the Human Aliens are planning on evacuating their 2 billion population to Earth, as their star is about to make their planet uninhabitable... and are willing to commit genocide to make space for their people.
- In an early episode of First Wave, Joshua reveals that the Gua homeworld is dying, and the conquest of Earth is primarily meant to allow the Gua to re-settle here. Strangely, a later episode has Joshua reveal that at least one other planet was conquered by the Gua prior to their arrival on Earth. So why didn't they settle there?
- Peter Schilling's "The Noah Plan": The Earth's orbit decays as it drifts towards the sun, and the people on Earth prepare for evacuation by "returning to the universe".
- During The Fall in Eclipse Phase millions of people uploaded their Egos to the sparsely-populated colonies in other parts of the solar system (uploading being the easiest means of space travel), while some others crowded the Space Elevators and crammed aboard ships.
- Classic Traveller, Double Adventure "The Chamax Plague/Horde". In the Back Story, the alien population of a planet was close to being wiped out by a Super-Persistent Predator species called the Chamax. They decided their only chance was to build a fleet of Sleeper Starships to carry all of the remaining aliens to other star systems.
- BIONICLE: In the Kingdom Alternate Dimension, Matoro fails to revive the Great Spirit Mata Nui, leaving the Matoran Universe in danger and prompt mass exodus onto the island of Mata Nui. Not all beings made it safely, but while many made it to the island, it is only a temporary refuge. The survivors settled quickly and also planned on how to leave the island for the stars.
- Homeworld: The Mothership was meant to be a colony ship before the Kushan even were aware of the threat to their existence, but when the Taiidan incinerated Kharak's atmosphere it became necessary to their survival as a species. Later on, they discover that they were descendants of the losers in a massive war who were forced into one of these.
- Earth, or Lost Jerusalem as it's called, is referred to often in Xenosaga. Humans had to leave it because of a mysterious space-time disturbance. Its location has been long lost. At the end of the third game a chunk of the party goes off searching for it, and we're left wanting another sequel.
- The backstory for its spiritual prequel, Xenogears, is similar. Humans left Earth in AD 2510 due to a space-time anomaly. The only reference to Earth in the game, though, is in the intro, and it is called "the main planet."
- In Outpost 2 the human race has fled from an asteroid-doomed Earth. The plot of the game revolves around the earthling colonists of a new planet and how they destroy themselves all over again.
- Another non-Earth example: The D'ni of the Myst series originated on a world called Garternay, which became uninhabitable when its sun began growing dim. Their ancestors fled into a succession of other worlds via their linking books, and have since lost all contact with their abandoned homeworld.
- In SimEarth, if the sapient civilization develops past the "nanotech age", an event called "the exodus" is triggered. All cities, regardless of tech level, are fitted with engines and take off into space. The planet is declared a preserve and left alone, possibly allowing a new sapient species to evolve. The motivation for the exodus is unclear.
- In the RTS Earth2150, this is the ultimate goal of all three factions, on account of the imminent Earth-Shattering Kaboom. Throughout the campaigns, you not only have to complete missions to cripple your rivals, but stockpile your excess resources in order to build a colony ship to carry you to another world before the countdown expires.
- According to the sequel, all three endings are canonical, which is strange given that it was clearly stated in Earth 2150 that there weren't enough resources to evacuate every faction. The Lost Souls expansion does indicate that a good number of people were left behind, though, and had to find alternative means of escape.
- In Mass Effect:
- This is a common last resort for species attempting to survive a Reaper invasion. Of particular note is a Side Quest to save the Elcor, whose homeworld is being assaulted, in Mass Effect 3. However, this only serves to delay the inevitable, because the Reapers are patient enough to spend centuries exterminating every last trace of all sapient life, no matter where they hide.
- Before the story proper, the quarian race escaped their homeworld to avoid being exterminated by the robot race they created, the geth. Worthy of note is that the geth allowed them to leave to avoid committing genocide.
- Also before the series proper, the drell were rescued from an overpopulated homeworld by the hanar, and felt indebted enough to work as their agents, laborers and assassins, of their own free will. The only downside is that moving from a nearly-desert world to one that's 90% ocean had horrible results on their health - any drell that spends more than a short time outside of their highly-maintained city contracts a terminal lung disease. Alas, in the context of 3, neither the drell nor the hanar get a chance to be extracted from the hanar homeworld, Kahje, if the indoctrinated hanar diplomat isn't stopped from shutting down their defences.
- As Mass Effect 3 proceeds, despite an epic display of resistance by the turians that costs the Reapers quite a lot of time, resources and ships, they are eventually forced to withdraw their surviving military from their homeworld, Palaven, and concentrate on the Crucible. Other races would have been evacuating civilians throughout this, but the turians - as Proud Warrior Race Guys - don't have civilians or even really understand the concept, and so military withdrawal is the closest to an evacuation they'll ever get.
- Freespace: The Vasudan homeworld starts an evacuation partway through the game as the Shivans draw near. Though quite a number escape, the Shivans arrive before they're done and four billion Vasudans die when the homeworld is subjected to Orbital Bombardment. In the sequel, Vasuda Prime is still uninhabitable.
- Starbound has this as the justification as to why humans are travelling the stars. Something took over the earth, and the whole species had to haul ass and find new planets to settle in.
- A variation in the Freelancer backstory. The Alliance evacuation is only partial and not from Earth, since Earth has been in the hands of the Coalition for many decades. By that point, the Alliance only controls a single moon and is about to be crushed by a huge Coalition strike fleet. The five Sleeper Starships manage to break through and jump away, while the remaining Alliance forces try to hold the line. The original trailer for the game also had an alien ship arrive after the exodus and blow up the Sun, making this trope true. Whether this remains a part of the canon is unclear. 800 years after the exodus, Earth and the war that caused the exodus are barely mentioned. People are more concerned with the present.
- In Orion's Arm Old Earth suffered a Grey Goo outbreak known as the Nanodisaster, but that's not why it was evacuated. The outbreak was nullified by an AI named GAIA and e decided humans were the worst threat to Earth so e told us to leave, before e sicced eir nanoswarms on us. E was considerate enough to build a fleet of ships first though.
- The Simpsons Treehouse of Horror has 2 ships to leave the earth with various stars. One goes to Mars, and the other to the Sun.
- A staple of the Transformers series.
- In Generation 1, the Autobot evacuate Cybertron as it has run out of Energon to support life.
- In Transformers Prime, the Autobots and Decepticons fled Cybertron when it became unsuitable to support them.
- In Superman: The Animated Series, Jor-El had a practical plan to evacuate the entire population of Krypton before it exploded: cast everyone into the Phantom Zone, have someone travel to a suitable planet and release them. However, the thought of being stored with the worse criminals of Krypton and Brainiac's self-serving lies made sure it wouldn't be used.