"'When did life start on your world? —And let me say, that's a nice hat.' And then he or she would say, 'It's my helmet, it's my space helmet, because your atmosphere is just—it's no good for me,' and so on. I'd want to know where they came from. I'd want to know why they wanted; what were they doing asking me what I was doing? It would be great to know, though, we're not alone. That would be a heck of a thing. It would change the world."
Since man has known what sort of sphere we live on, we have looked at the stars and wondered: are we alone? In this vast, empty Universe, are there any other intelligences gazing up at our star from under an alien moon?
A common theme in Speculative Fiction, science fiction writers have loved to speculate for decades what that pivotal moment will be like: the day we first make contact with an extra-terrestrial intelligence. Writers have invented everything from truly Starfish Aliens to Rubber-Forehead Aliens and every scenario from aggressive aliens or humans to peaceful coexistence, and everything in-between.
The name for the trope and the term itself comes from the 1945 Murray Leinster novelette First Contact. This is not the same as first contact, lowercase, which describes any first contact between two cultures.
Expect someone to make a statement or speech about what a pivotal moment this is for the human race. You may find religious fanatics who claim the aliens are devils, angels, or even gods. Unless the aliens are Sufficiently Advanced or it is Handwaved, there may be communication difficulties and misunderstandings, sometimes leading to outright warnote Sometimes the war is the first contact. Scientists will want to study the aliens, ofttimes without the aliens' consent. The aliens will usually be more technologically advanced, although not always more sociologically advanced. A specific group of specialists may be formed to create a First Contact Team in order to plan for every contingency.
If taking place in America, it may turn out that First Contact actually happened decades ago in Roswell, New Mexico, and that the government has been keeping it under wraps ever since.
Speculation about First Contact scenarios has led many scientists and philosophers to consider that the human race may not be ready for such contact — they often argue that the multitude of armed conflicts and the pollution of our own world as reasons that an extra-terrestrial lifeform may pass Earth by, which Hollywood will pick up on when they feel their movie needs a message.
Compare Alien Among Us. Contrast with Absent Aliens. See also First Contact Math, Boldly Coming, Faeries Don't Believe in Humans Either.
For the film, see Star Trek: First Contact.
Naturally, this is the step between The Masquerade and The Unmasqued World.
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In the Macross universe, First Contact occured during Super Dimension Fortress Macross between the humans and the Zentradi, which resulted in the near-total desolation of earth and the annihilation of a large Zentradi fleet in its skies. The main conflict (but not the bitterness) ends when the two sides manage to communicate and realize that they're not so different after all. Oh, and with the songs of an idol singer. Can't forget about that.
It is worth noting that the fleet destroyed during the series was not the main fleet of the Zentradi. There is no such thing, really. It was actually just one of hundreds of similarly-sized fleets that are still patrolling the galaxy locked in an endless war with the Supervision Army, who themselves are just Zentradi that served a different faction of the now-extinct Protoculture. The fact that utter annihilation could stumble upon them at any moment is the driving force behind the combined Human/Zentradi settling of every possible planet they can find in later Macross series.
The Gundam 00 movie, Awakening of the Trailblazer, deals with First Contact with an alien species called the ELS. The two species are socompletely alien to one another that humanity mistakes their attempts at communication for hostile attacks.
In Worldwar: War of Equals, when The Race's fleet is spotted just outside the solar system, Humanity tries to go for a peaceful version of this with America and Europe using SETI's ATA and China using a system developed in Yantai Space City. The Race refuse to take the offer for peace.
The film Transformers has a sort-of First Contact when the explorer Archibald Witwicky discovers a slumbering Megatron in the early 20th century. Though Megatron is kept insensate, humanity gets a technological jump start from what they learn of his workings. More commonly seen first contacts take place later, when the Decepticon Blackout and his little friend Skorponok flatten a US military base in the Middle East, and the Autobots track down Archibald's descendant, Sam, and ask for an artifact from his ancestor. They learned their command of English from the Internet. Despite battling with the Decepticons in public, the Autobots are presumably covered up by the government, and they remain on Earth, in disguise, watching and protecting and waiting for their fellows to join them.
Contact (based on the Carl Sagan novel, mentioned below).
In the Soviet cult classic Moscow — Cassiopeia, humanity receives a signal from a faraway star. The Soviet government builds a nuclear-powered relativistic spacecraft and crews it with high school kids, realizing that they would be adults by the time the ship arrives. However, a stowaway sits on the engine controls and somehow accelerates the ship beyond the speed of light. Long story short, they arrive to their destination in the blink of an eye (for them, at least) and encounter an alien ship. The Captain gets into a transparent dome on the hull and tries to communicate with the Human Aliens with hand gestures. They appear to understand and reply in kind. Later, the teens use a Universal Translator they brought to teach the aliens Russian in a matter of seconds. They find out that the aliens they met are the last of their race due to a robot revolt some time ago. Only those who were in space at the time escaped. The rest were "enhanced" by the machines by having their emotions removed, thus stopping procreation (apparently, love is a prerequisite for sex). The humans offer to help the aliens retake their homeworld.
Oblivion (2013) : What the "Odyssey" mission was meant to be (meeting an unexplained space object near Titan). To say that it Went Horribly Wrong is a massive understatement.
Man of Steel greatly deconstructs not only the concept of a superhero appearing for the first time, but humanity finding out that they're not alone and not even close to a match for their competition.
In Prometheus the main characters' goal is to make first contact with the Engineers that created humanity. After waking the last surviving one up, he immediately attacks them and tries to wipe out humanity with the Engineers' bioweapon.
An unintentional one in Planet 51, where the protagonist is an astronaut sent to a supposedly-empty planet only to find that he landed in the middle of an alien neighborhood BBQ party. This is portrayed as a First Contact from the aliens' viewpoint, who immediately assume the astronaut is hostile. It turns out the reason why no one on Earth knew about the aliens is because the robot sent to scout out the world prior to the manned mission is obsessed with rocks and didn't bother sending any images of aliens.
The novel Contact by Carl Sagan deals with first contact in a relatively "hard" manner. Aliens in a system twenty-six light years distant send a radio signal to Earth - a long sequence of prime numbers. It's a palimpsest, and under it is a second message that turns out to be an audio/video signal, a repeat of the first few minutes of the first television signal broadcast strongly enough to traverse out to Vega - which, unfortunately, turns out to be Adolf Hitler's Olympic commencement broadcast. This, too, is a palimpsest, and under that is the blueprints to a machine. Even this is a palimpsest, for there's a primer buried in there telling Earth how to build it.
Ender’s Game by Orson Scott Card, although in this case the contact occurred in the backstory when the insectoid aliens (colloquially termed "Buggers") sent an invasion fleet to Earth's solar system. The only interactions anyone has with them in the first novel are violent. In the epilogue and subsequent novels, it's up to Ender to make a true First Contact by being the first of his species to successfully communicate with a Hive Queen.
The prequel comic Formic Wars and the novels (expanding on the comic) describe the arrival of the Formics (nobody uses the term "Bugger" now) into the Solar System and the devastating First Invasion. 44 million Chinese are killed, and a large chunk of China is covered by a deadly acidic gas. And that was just a single mothership that was barely defeated. The final shot of the comic shows a whole fleet of these on the way, with the humans creating the Hegemony and the International Fleet to prepare for the second arrival, using the mothership to reverse-engineer Formic tech.
Poul Anderson's novelette The Enemy Stars deals with an accidental First Contact between a human and the aliens that save his life, and the sequel The Ways of Love deals with how humans handle the first alien beings on Earth (not well, in some cases).
The prequel novel to Mass Effect, Mass Effect: Revelation deals with the start of the First Contact War mentioned below in its prologue. Interestingly, even this novel doesn't really describe the first contact or the subsequent conflict. Anderson is merely told by his superior about the attack on human ships and the retaliation on the turians. Of course, the existence of aliens isn't really news, since the exploration of the Prothean ruins on Mars is what allows humans to develop FTL travel.
The Mote in God's Eye. Inverted in that humans have the star-spanning empire, while the aliens are trapped on one single world.
The Contact section of the Culture in Iain M. Banks's novels, described as the "good works" agency of that society, apart from Contact's "Special Circumstances" division, who interfere in other civilisations if it looks like they'll be trouble to the Culture. A kind of Reverse Alien Non-Interference Clause.
An interesting variation on First Contact occurs in The Algebraist, another of Iain M. Banks's sci-fi novels. It is mentioned that humanity - (perhaps just human genetic material) - was transplanted from Earth to a number of nearby worlds in 4051 BC. These humans were raised in an interstellar culture while Earth itself was declared off-limits. Result; by the time Earth discovered interstellar travel, Human Aliens, or aHumans outnumbered the remaining humans or rHumans by an order of magnitude. First Contact was less We Come in Peace — Shoot to Kill then What Kept You? As a method of preventing every First Contact boondoggle ever theorized, it worked. It also annihilated all terrestrial human culture.
Encyclopedia Exposita: Prepping. A very long-established practice, used lately by the Culmina amongst others, is to take a few examples of a pre-civilised species from their home world (usually in clonoclastic or embryonic form) and make them subject species/slaves/mercenaries/mentored. so that when the people from their home world finally assume the Galactic stage, they are not the most civilised/advanced of their kind (often they're not even the most numerous grouping of their kind). Species so treated are expected to feel an obligation to their so-called mentors (who will also generally claim to have diverted comets or otherwise prevented catastrophes in the interim, whether they have or not). This practice has been banned in the past when pan-Galactic laws (see Galactic Council) have been upheld but tends to reappear in less civilised times. Practice variously referred to as Prepping, Lifting or Aggressive Mentoring. Local-relevant terminology: aHuman & rHuman (advanced and remainder Human).
Sci-fi author Peter F. Hamilton discusses the devastating effects on the economy of an advanced alien technology in The Nano Flower and the short story Escape Route.
The classic short story "First Contact", by Murray Leinster, details the dilemma of a human and alien spacecraft making first contact in space. Neither ship can risk the other following them back to their home world, so the two crews have to either destroy each other, or establish some kind of mutual trust. Of course, establishing trust means exchanging information, and should the other side prove to be hostile...
Ivan Yefremov's novella Cor Serpentis is essentially a one big Take That at Leinster's spin on the theme. Both Yefremov and his characters take it as extremely distasteful and, believing that no spacefaring civilization might be hostile, meet the aliens with open hands, in one of the most touching description of contact ever written.
Subverted with extreme prejudice in the Harry Turtledove story "The Road Not Taken", in which Earth has first contact in the form of an alien invasion.... by Aliens that are less advanced technologically than Humanity in every single aspect other than space travel. They literally attack with flintlocks and swords. It turns out that basically Anti-Gravity is ridiculously simple and most species discover it during roughly the Age of Sail. Although the ending of the story makes it appear that Humans are a Mary Sue, a sequel subverts the premise by having Humanity be the less advanced one.
Turtledove has also had it in some other stories: in World WarFirst Contact comes in 1942 as the result of an Alien Invasion, and in A World of Difference it's humans landing on an alternate Mars inhabited by primitive aliens in the 1990s.
Halo: Contact Harvest details the UNSC's first contact with the Covenant from the perspective of both human and alien characters.
Blindsight by Peter Watts features an interesting subversion. The alien Scramblers turn out to be hyperintelligent but not conscious or self-aware, and can only parse human languages as space-wasting cognitive viruses designed to hurt them. "How do you say "We come in peace" when the words themselves are an act of war?"
Infinity Beach begins on a human colony world making a final attempt to communicate with any possible life Out There, but the conclusion appears to be that mankind is alone. Unknown to all concerned there had been a First Contact some years before but it was bungled, with all the aliens and several humans killed; ashamed of their error the survivors covered things up. When the protagonist discovers this the government decides the best thing is for humanity to lay low, for if the aliens weren't hostile before, they undoubtedly will be now! Against orders, a group of scientists decide to risk another Contact. Fortunately the aliens accept their explanation that it was all a mistake, and peaceful relations are established.
In Omega (part of the Priscilla Hutchins series), an intelligent species is discovered directly in the path of an interstellar catastrophe. The species has begun to develop technology, but is still at a pre-spaceflight stage of development. Researchers determine that the technology they have may be enough to save most of their population if they can be persuaded to apply it properly, but the Alien Non-Interference Clause makes the first-contact team's job difficult. Disaster is approaching rapidly, and the team needs to learn as much as they can about the language and culture of the Goompahs, starting from zero. But how do you persuade some alien creatures to cooperate in saving their species if you can't even reveal your own existence?
The Hercules Text, published almost simultaneously with Carl Sagan's Contact, has a very similar premise: signals are received by Earth via a radio telescope which contain mathematical information that turn out to be the key to a later transmission containing a great deal of scientific information. The effect of all this on the peoples of Earth is dramatic.
The Hitchhikers Guide To The Galaxy parodies this, of course. Humanity's ostensible First Contact with Galactic civilization is with the Vogons, who are here not for chitchat but to destroy Earth to make way for a hyperspace bypass. It's subsequently subverted in at least four separate ways, which ought to be It Was His Sled by now:
Earth's been visited by aliens for ages, we just never realized it.
The Earth is actually a giant supercomputer built to calculate the Question to the Ultimate Answer of Life, the Universe, and Everything.
Humans are themselvesAncient Astronauts and not the originally planned sapient inhabitants of the planet.
Due to a temporal anomaly, Earth had a First Contact event prior to the Vogon demolition of Earth: an alien warfleet attacked Earth but due to a miscalculation Earth - or at least Humans - never noticed as the warfleet was swallowed by a dog.
In Sergey Lukyanenko's The Stars Are Cold Toys, First Contact happened during the first extrasolar jump, which coincidentally put the space shuttle near a Conclave ship. One of the crewmembers is interrogated by the aliens, and she reveals the location of Earth. She is later tried for treason but acquitted, as the defense claimed the aliens Mind Raped her. Thus humanity becomes just another cog in the ruthless Conclave regime. Slightly subverted due to humans being descendants of the colonists from the Shadow.
In Vladimir Vasiliev's Death Or Glory, humanity's first contact with The Alliance takes place after the discovery of FTL travel. A Svaigh ship lands in the middle of a British city and incinerates a Special Forces team sent to it. They demand a few tons of beryllium and take off. This repeats a few times, but, for the most part, they leave humans alone. Could've been worse, as at least some of The Alliance races are known to have conquered younger races and kept them as slaves. This becomes a major plot point in the later books of the series.
The first contact that accidentally happens in Mrs. Mc Caffrey's Decision at Doona isn't technically mankind's first first contact, but the fact that that first-ever alien culture encountered committed mass suicide in response drives much of the novel's plot by informing the human policies established afterwards to prevent anything like that from ever happening again. One of these is "non-coinhabitation"; humans aren't allowed to live on the same planets as intelligent alien lifeforms, period. Which creates a problem when the first human settlers on the new colony world of Doona run smack into just such an intelligent alien lifeform that the initial surveyors somehow managed to miss... Because the "natives" are actually new colonists from another planet, who find themselves in the same boat!
In the backstory of Alan Dean Foster's Humanx Commonwealth universe, humans and Thranx both have first contact with the violently xenophobic AAnn shortly before coming into contact with each other, taking what might otherwise have become a violent war and turning it into an Enemy Mine situation that evolves into the two species becoming close allies.
In the Kir Bulychev novel The Mystery of Urulgan, first contact occurs when a small band of adventurers finds a spaceship that crashed in Siberia. The alien assumes the humans will be civilized, and shows them his technology, but all that ensues is conflict between the adventurers and attacks on the alien, who finally escapes.
In the Doom novels, humanity's First Contact with the aliens on the other end of Mar's teleportation network was an Imp throwing a flaming ball of snot into the crowd. It went downhill from there.
In The Killing Star, first contact with the aliens consists of them slamming relativistic missiles into the Earth, nearly wiping out humanity.
Mikhail Akhmanov's Invasion describes first contact with the Bino Faata, whose starship has arrived to the Solar System in search of new races to conquer and integrate into the Faata hierarchy. The novels title and The Teaser (before cutting back to how it started) are clear examples of the bad kind of first contact. Humanity barely survives the assault with tens of millions of dead all over the world. On the bright side, the Faata starship remains mostly intact. From it, humans reverse-engineer the contour drive, Deflector Shields, and Anti Matter weapons. The second novel takes place 37 years later and involves a newly-created battlegroup taking the fight back to the Faata. Also, in-between the novels, a proper First Contact takes place with the peaceful Lo'ona Aeo, who wish to trade with humans.
Raymond Z. Gallun's "Old Faithful" (1934) is one of the earliest science-fiction novels to deal in detail with the difficulties of making long-range signal contact with ''very'' alien aliens. The in-story solution, which begins with basic mathematics, is the method which was also chosen by most SETI scientists from the 1950's on.
Seen from a nonhuman perspective in one of the infodump chapters of The Romulan Way. The Vulcans' first contact was disastrous, as it took place with the predecessors of the Orion Pirates. The Vulcans fought them off but the aftereffects were one of the triggers for the Sundering between the Vulcans and the Rihannsu (everyone else calls them Romulans). A couple thousand years later the Rihannsu, not warp-capable but who had shipbuilding capacity to support trade between ch'Rihan and ch'Havran* the planets the Federation calls Romulus and Remus detected a ship in orbit and linked it in their minds to the pirates of millennia earlier, and reacted accordingly. Unfortunately for all involved, the ship belonged to the Federation.
In one of the short stories in the companion volume to Penn & Teller's Cruel Tricks For Dear Friends, humanity is set to be eradicated by an alien empire whose hat is destroying redundancy. It seems that everything that (we naively believe) makes humans unique is actually duplicated somewhere else in the galaxy, and the aliens see no sense wasting a prime habitable planet on such a bog-standard redundant species. The main character saves the human race with a magic trick, implying that deceiving one another by sleight-of-hand for amusement is the one uniquely human art form.
In Plague from Space, a ship sent to explore Jupiter returns, releasing a deadly disease that rapidly mutates and kills people. Eventually, a special forces group makes its way aboard the ship and watches the videologs, which reveal that the solid core of Jupiter is inhabited by a Hive Mind race whose hat is Organic Technology. The crew of the ship learned to communicate with the Jovians, but the Jovians eventually moved on to dissections. The remaining crewmember was sent back along with a Jovian passenger, infected with a disease engineered for humans. It turns out that the whole plague thing is nothing more than an attempt by the Jovian Hive Mind to study humanity, whom it perceives as also likely a Hive Mind. After the end of the "experiment", the Jovian passenger transmits the results to Jupiter, gives the humans the cure, and dies.
In Invasion: Earth, a spaceship crash-lands in New York's Central Park. Since the book was written during the Cold War, the Soviets send a representative (a female linguist) to join the First Contact Team that enters the craft, mostly composed of American soldiers. Inside, they are attacked by a Wookie-like creature, which they riddle with bullets. They find a chained-up white-skinned Human Alien who speaks English and Russian from aliens intercepting the most common radio-broadcasts. The alien explains that Earth has been targeted for invasion by their bitter rivals Blettr (the hairy aliens). The Oinn, the alien's people, offer to help by setting up a base in the Antarctic to defend Earth using their advanced weaponry. The Blettr fleet arrives, and the Oinn battle them. They manage to fight off the first wave, but several human cities are wiped out by Orbital Bombardment. The authorities begin to doubt the truth when the Oinn refuse to let humans anywhere near their base and forbid them from attempting to communicate with the Blettr. In the end, it's revealed that the Blettr and the Oinn are Planet Looters who are working together to get as much radioactive material from Earth as possible before moving on, looking for their lost homeworlds. The humans manage to fight them off and bluff them into leaving the system, while keeping a small ship to reverse-engineer.
Live Action TV
Played with in Farscape: in S 01 E 07, I, E.T.'', Moya has to land on a backwater planet because of a beacon put on her that could alert the Peacekeepers, and removing the beacon is a surgical procedure that could kill her. John and the others go in search of an element that can serve as an anesthetic for the procedure and meets with some of the locals... who are flabbergasted at meeting an hones-to-goodness alien. Yes, a human is the first contact of another sentient species.
The very beginning of V (both the original series and the remake). Alien ships appear over Earth, and the humanlike aliens promise that they have come in peace and want to establish relations with mankind. Their motives and nature turn out to far more sinister.
In the episode "Aliens of London". The Slitheen hoaxed a "first contact" situation as part of a plan to destroy the planet.
There have been a few real, official first contact situations on the show. None ended well.
There's an inversion of this in a very early episode of Farscape where the human main character finds himself crash-landing on a small alien farm and having to dodge government agents while trying to mend the spaceship.
Also happens on Earth multiple times throughout the show, though the first few times it was All Just a Dream. Eventually it happens for real, though.
One memorable episode starts with a new US President being inaugurated only to be whisked away into a bunker deep underground when objects are detected approaching Earth. There's plenty of misunderstanding, as the humans have no idea what the aliens are planning. Meanwhile, the President's efforts to maintain peace are theatened by Russia's gung-ho attitude to the aliens, eventually forcing the President's hand. The bitter irony is revealed at the end, just before Washington, D.C., and Moscow are obliterated in retaliation. The aliens were speaking English all along, but their message was distorted by their aquatic environment. It was a message of peace.
Another episode involves a human ship landing on an Earth-like world and encountering a group of seemingly primitive aliens. The scientists are keen to make contact and study the locals, while the military types want to wipe out the locals to make room for a future colony. It turns out the "primitive locals" were the equivalent of Boy Scouts on a camping trip and weren't even from this world. When they call for help, a powerful alien ship shows up, downloads the human ship's navigational charts, and heads straight for Earth to exact revenge.
Hilariously spoofed in the comedy series Hyperdrive, most notably in the Queppu episode.
Ironically for a show revolving around specialists in alien diplomacy, the Enterprise-D was pretty bad at it. Their crewmen were captured, their surveillance apparatuses blown wide open, their technology pillaged. When the Federation is probed by a heretofore unknown race (and not the other way around), things typically go much smoother.
The self-titled Next Gen episode, "First Contact", depicts a First Contact gone awry. The species in question erases all evidence of their encounter with Picard's crew, believing that divulging the existence of aliens would cause panic and civil unrest. Even some warp-capable species want nothing to do with those weirdos.
"Who Watches the Watchers" had the opposite effect Starfleet intended, with Picard accidentally rekindling the Minatakans' belief in a wrathful god.
Sometimes when First Contact occurs between two alien species, the results have been less than happy. The Cardassian Union landed on Bajor and proceeded to herd everyone into ore mines. They later claimed they were a backward race and disputed that Bajor had achieved space flight first (they had).
Earth has at least one truly disastrous first contact in its back story: The first contact of humans and Minbari happened between two warships. Recognizing the strangers as fellow warriors, the Mimbari lowered their shields and readied their weapons as a weird gesture of transparency; Earth's forces sensibly shot at them while their defenses were down; the warrior caste, not ones to turn the other cheek to insults (or turn down a good bloodbath) proceeded to make mincemeat of Earth's military. They would have wiped out every last human if they could.
Apparently, the warrior caste was attempting to say "my hands are empty" by opening the gunports but keeping them powered off.note Dukhat, to his credit, realized it was a bad idea, and ordered the gunports closed as soon as he heard about it. The problem was that the Earth Alliance ship couldn't detect whether or not the weapons were armed. Between that and the Minbari sensors accidentally jamming the Earth cruiser's jump engine, it's no wonder the captain thought he was under attack. It's also mentioned that the captain in question doesn't have the best diplomatic track record. Sheridan questions the brass sending that guy. They also disregard Londo's suggestion to send a single, small ship in order to avoid provoking the ancient and powerful Minbari. Still high on their laurels over beating the Dilgar, EarthForce didn't think the Minbari were that powerful. They were.
First Contact was also made with the Centauri, who tried to con the silly apes. Other races seem to have had pretty bad experiences too from time to time.
Interestingly, Earth got away lucky in the first contact with the Centauri: where most races have first contact with the Centauri in the form of an invasion fleet or get conned into becoming economically subservient to them, Humans were found more interesting free and were not invaded, and managed to not get conned.note There was a minor con attempted early on, where the Centauri attempted to convince the humans that they were actually a lost Centauri colony—which, given their outward similarities, was almost plausible. The con fell apart, though, once the humans got a hold of some Centauri DNA. Other races were not so lucky (there's a good reason if the Narn hate the Centauri so much).
One episode deals with a probe that gives the people on the station a short amount of time to answer various complex mathematical and scientific questions before it blows up, as its creators believe only races that can answer them deserve to live. However, Sheridan figures out it's actually designed to kill anyone who can answer the questions, whom the aliens consider a possible threat.
Notably averted in Power Rangers, where hostile aliens attack on a weekly basis for six years (without any diplomatic contact of any kind!) before anyone friendly enough (and not focused on perpetuating The Masquerade) to speak to officials or the public at large shows up. By that point, everyone is fairly certain that there's life on other planets; its the reason property values in Angel Grove have fallen so much recently.
The real First Contact in the Stargate Verse (not counting Transplanted Humans abducted thousands of years ago, or the Precursors who happened to evolve here millions of years ago (sort of, maybe)) happened in 1994, when a top-secret Air Force team used an ancient alien artifact to travel to another world, where they found Transplanted Humans being ruled by a Puppeteer Parasite. More than 15 years, 300 episodes, three TV series and two made-for-TV movies later, despite the creation on Earth of half a dozen ships capable of interstellar travel and at least two battles in Earth's atmosphere or in orbit between humans and aliens, the existence of aliens is still apparently a secret from the general public.
This trope has also been inverted several times, when we see First Contact from an alien (well, transplanted human) point of view. In general, the aliens' government covers it up just like ours if they are advanced enough to do so, but there have been several exceptions.
In The X-Files, humans were contacted, abducted, and experimented upon for millions of years but the first contact between the alien Colonists and human authorities took place, as far as we know, in October 13, 1973, giving rise to the shadowy Government Conspiracy to hide the truth. It is also of note that the contact was made possible by extensive reverse-engineering of the alien craft recovered from the Roswell Incident.
Dark Skies also has the first contact between the Hive and the American government take place in secret. The President has a face-to-face meeting with an alien representative, who telepathically demands Earth's unconditional surrender. In response, the President creates the Majestic 12, whose job is to cover up the existence of aliens and fight their attempts to infiltrate humanity using any means necessary.
Vaguely mentioned in an episode of Sliders, after they end up in a world with a more advanced level of technology. It turns out, due to World War II continuing for several more years in this world, a different US President got elected just in time for the Roswell incident. Instead of covering it up, this President decided to make the existence of aliens public knowledge. Shortly after that, the Reticulan-American Free Trade Agreement (RAFTA) is drafted, allowing a good amount of Imported Alien Phlebotinum to be ubiquitous by the end of the 20th century, as well as a manned mission to Mars. No aliens are actually present in the episode, but one of the locals is a human who has been accidentally turned into a Half-Human Hybrid with a gene therapy that cures most known diseases.
In Mass Effect, first contact with aliens leads to a war with the turians, which is then dubbed the 'First Contact War' (though this happens several decades before the start of the game). The casualties on both sides of the war is the cause of much conflict between turians and humans. It was basically a classic example of Poor Communication Kills coupled with an inability to communicate and horrible judgment. The turians found a human merchant group of ships opening a mass relay—something that's illegal by Citadel law, but also something that humanity would not know of. Because randomly opening mass relays lead to a costly Bug War, the turian patrol opened fire on the merchant ships, but one got away. Cue a short but heated conflict in which the number of casualties is altogether very low for an interstellar war, but allows humanity to prove its military prowess despite having absolutely no experience with space combat. Hostilities ended when the Citadel Council stepped in and reprimanded the turians for shooting before asking questions, and allowing humanity to step into the greater galaxy in peace.
Inverted in the first three Star Ocean games, in which we focus on an alien species who learns that they are not alone in the Universe.
The prequel, Star Ocean: The Last Hope, features Earth in the beginning of its spacegoing existence. Not only does it feature Earth's First Contact (with Eldar via subspace radio), but the main character initiates and/or encounters the aftermath of so many First Contact situations that go/went horribly, horribly wrong that he persuades Earth to set up a prime directive.
As mentioned under Literature, Halo doesn't have nice first contact. "Hello, you are too close to our holy sites. Our Gods demand your genocide." It goes downhill from there until Halo 2.
Which, as Halo: Contact Harvest reveals it was all a lie by the new Hierarchs, who discovered from a Forerunner AI that Humans Are Special and wanted to wipe them out in order to preserve their religion and their power.
And even then, it only became full-blown war because of one nervous and Trigger Happy Grunt.
A few Final Fantasy titles deal with first contact, most of them bad experiences:
Final Fantasy IV: Goes good (advanced technology) and bad (mad scientists, rampaging mechs.)
Final Fantasy VIII: Goes very bad (The moon contains monsters and ended at least one civilization)
Final Fantasy IX: Goes extremely bad (Culminates in the destruction of one planet, and apocalyptic events for the other)
Starcraft: The Federation has experimented on Zerg for a while and already knew about the Protoss but the "official" first contact with both races involves a planet getting overun with the Zerg and then getting blown up by the Protoss.
The Warcraft franchise started with the people of Azeroth's First Contact with the Orcs of Draenor which doubled as an Alien Invasion. The Orcs were so vicious that the Humans thought they were demons. Which wasn't too far from the truth.
In the X-Universe, humanity knew there were (or at the very least, had been) aliens out there somewhere since 2041, when one of the jumpgates they built locked onto a gate of alien origin. But they wouldn't actually meet aliens until 2300, when the Argon Federation encountered the Paranids. The Argon and Paranids ended up allies and trading partners for a while, but then the Paranids elected not to help the Argon fight the Xenon and things went south.
The interludes popping up throughout Sid Meiers Alpha Centauri reveal that Planet is a Genius Loci. One of the endings involves blasting the combined human knowledge into the Planetary mind in order to force Planet to "mature". It works. The Transcendence victory has the humans then joining Planet's Hive Mind. The Expansion Pack involves a more traditional First Contact with descendants of the aliens who created Planet. In fact, the contact is with two of the factions of the same species, who are engaged in a bitter ideological war over Planet (AKA Manifold Six). Human factions can't communicate with Progenitor factions until either one researches a certain technology (Social Psych for Progenitors, Progenitor Psych for humans).
An interesting version in Civilization: Call to Power. One of the endings involves discovering a wormhole in Earth's orbit and sending an unmanned ship through to collect some samples. The ship comes back with samples of alien DNA. The final task is to create a cloning lab to make new aliens.
We later learn that her people's first contact with Earth's pre-human civilization of dragons went very, very badly.
In Freefall humanity has made contact with a few alien races, though mostly aliens of the starfish variety so relations are limited. Also many humans were wary of accidentally causing an interstellar incident when first meeting Florence or Sam (until they realized that Florence wasn't an alien and Sam was annoying).
When they found Sam's species, the summary was "keep searching".
Vexxarr falls (ahem) into this situation frequently enough, so when he doesn't see natives...
Vexxarr: From two unarmed alien bags of fluid gastropodding across their local gren space? We should have seen either their military or their nerds by now.
In Loon Land the alien Lana Loon lands on earth and has a close (failed sexual) encounter with the terrestrial loon Mike Moon .
Mike: Hang on! You've got like five holes down here! Which do I poke it in?
Lana: All of them.
The issues involved are explored on this page of the Atomic Rockets website.
Should you have come on this page with the intent of finding help, this page should hopefully provide.
In EdStories, First Contact is established about 85 minutes after the Andromedans aimed an asteroid into the Earth at 10% light speed.
The Journal Entries doesn't cover the actual first contact of Earth in any detail (there are two different things that could count, but the one described at all is just Ken visiting himself in his subjective past on Earth to give himself the Applied Phlebotinum that kick starts the whole series, and that's just mentioned in passing). The first contact between Pendor and Eareth kind of weirds Earth out not because Pendor is peopled by furries with amazing technology and weird social standards, but because Pendor desperately wants Earth culture. (At this point, Pendor has existed for something like a century and everyone is desperate to get at the deep, rich cultural materials Earth has accumulated over several thousand years.)
The Futurama episode "When Aliens Attack" involves first contact between Earth and the people of Omicron Perseii VIII.