First Contact / Fan Works

• 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.
• This is the premise of Mass Effect: Clash of Civilizations, as the Council races encounter the humans of the UNSC.
• Humans in Transcendent Humanity first discover carvings left behind by the Precursors, prompting them to unite, colonize the Solar system, and ramp up their scientific and industrial output. Eventually they make contact with other civilizations in the galaxy, and outclass them in almost every way.
• In Harry Tano, this happens when Ahsoka Tano meets and subsequently adopts a young Harry Potter. It is later lampshaded by Margaret Thatcher when she realizes the Ministry of Magic botched up the official First Contact due to being paranoid prats.
• In Mega Man: Defender of the Human Race, Episode 14 features the Stardroids, alien robots who do not come in peace.
• The Next Frontier features a Perspective Flip of sorts, as the big moment unfolds largely from the perspective of a non-human species, namely the Kerbals.
• Subverted in Discworld and The Big Bang Theory crossover The Many Worlds Interpretation. The Caltech nerds (and Penny) are the first to make contact with "aliens" - who turn out to be from the Discworld. One of the visiting aliens is young, red-haired and attractive enough for Howard Wolowitz to forgo the usual "take me to your leader..." stuff. His first words to the alien visitor are Are all the women on your planet as hot as you?. An "alien" visits. Howard makes a pass at her. And when the Caltech crew visit the Discworld, a specialised aspect of quantum theory allows them to take the Internet with them. An Unseen University faculty member, given a resource allowing him (at least in theory) to tap into the accumulated knowledge of an entire planet, immediately asks if you can get lots of pictures of, er, young ladies, in artistic poses with urns and lengths of gauze. Yes. The Senior Wrangler immediately latches onto Internet porn.
• Equestria: Across the Multiverse:
  • The mane theme and idea of the story is interuniversal exploration and contact, so first contact with alternate universes is a frequent occurrence. Twilight has a detailed list of how they're supposed to do it, but never gets to actually do it. The My Little Pony Tales arc is the one that follows the mold most closely.
  • Eventually, the tech leap that Equestria Prime makes results in a race of aliens called the Celestial Ponies making an organized First Contact. They come in peace...except one of their supervillains, Black Star the Light Stealer, who also arrived and made First Contact with Queen Chrysalis.
• Integration: This is one of the main plot lines. The human world is slowly gaining more magic stability and pretty soon it will be impossible to hide magic from the population outside of CHS, so the ponies in Gaia (pony world) and the humans in Terra (human world) work together to prepare for official contact and for the two worlds to become inter-dimensional allies. Sunset and Princess Twilight also have plans for when contact is made, Sunset planning to help the citizens of Terra adapt to the magic they will receive and Twilight hoping to bring technology from Terra over to Gaia.
• In Wander over Foster's AU One-Shot, Wander lands on Earth and ends up stranded at Foster's. Most planets have inter-planetary travel but Earth is one of the few exceptions. No one even knows about alien species on Earth. Due to this, everyone assumes Wander is a standard Imaginary Friend and only Bloo realizes that he isn't.
• The Victors Project uses this as the motif for District 1's first encounter with people from the Capitol. The Capitolians first come in flying ships and had "skin of black and brown and gold and blue and scarlet, with hair of every hue and jeweled tattoos." When the District 1 citizens respond violently, the Capitolians return in a more Alien Invasion style, with a full army.
• In crossover fanfiction Point Me at the Skyrim, Victoria Dallon gets transported to the Skyrim world. Vicky briefly considers the various First Contact Protocols when it comes to interacting with alternate Earths, and how she would technically be breaking several laws by approaching the inhabitants without proper authority figures. The situation is dire enough that she doesn't care.
• It happens in To Hell and Back (Arrowverse) shortly after Oliver Queen and Barry Allen end up stranded on Lian Yu. When a shockwave rocks the entire island, Ollie and Barry head towards the impact site and find two aliens stumbling out of a spaceship.
  The impact is heard throughout the island, a shockwave spanning out for miles. Edward Fyers immediately sends out a scouting team.
  Oliver and Barry get there first.
  Barry is frozen on the spot. Beside him, Oliver is not much better, pointing and shaking.
  A spaceship. An honest-to-god spaceship.
  They stare, and continue to stare, until the cockpit snaps open, and a blonde-haired girl spills out, with a baby in her arms. She stumbles a bit, before gaining purchase with the ground, and looks up at them.
  "Who are you?", she asks in a language that neither they, nor anyone else native to this planet, knows.
• Daughter of Fire and Steel: In order to find Kal-El, who is masquerading as a human, General Zod has his starship enter the Earth's atmosphere, and then he begins his global broadcast with a "You are not alone" message to the Earth's people.
• Arrow 18 Mission Logs: First contact between Earth and Equestria is from a ship from Earth to investigate the Equestrian world (namely the fact that it's sun is orbiting the planet, and not the other way around) and discovering signs of civilization.
• If Wishes Were Ponies: First contact happens when a badly injured Harry Potter stumbles through a portal to Equestria. The portal is eventually rediscovered by the Equestrians, who proceed to make contact with the British government. Specifically the Muggle one due to the Wizarding one being laissez faire to the point of negligent.
• Saphroneth's experimental short story Starlight goes into the details of how an unfamiliar species might use a "first contact" transmission to build communication from the very first principles. Counting from 1 to 20, sending sequences of triangular and prime numbers to establish that the transmission is meaningful; sending monochrome bitmaps using prime numbers as their resolution size so that there are a limited number of ways to interpret the bits, with a plain circle as the "check" to verify that you're arranging the data the right way; then with an image format established, sending pictures of mathematical equations to establish the numerical and arithmetic symbols, etc. The Empire disregards the package as gibberish and opens fire, but Rebel forces later take the time to examine the transmission and realise what it is.
  The next little breakthrough came once Morgan noticed that the length of the repeated section was three prime numbers multiplied together. They were all large primes, which meant it wasn't just a size for the data chunks — something he'd wondered about — and after a few minutes Morgan told WeeGee to arrange the first part of the repeated information as if it were a black-and-white image.
  There were six possibilities, with six primes, and five of them looked distorted or unclear. The sixth was a perfect circle drawn out in white on a black background, and when that appeared Marie stepped back in surprise.
  "How did you do that?" she asked.
  "It's primes," Morgan replied. "Probably deliberate. You've got a string of data with a length that has three prime factors, only so many ways to arrange it… so we've now upgraded to images. Let's see what else we have."
• Tarkin's Fist: Occurs in the late 2030's between Earth and the four sector fleets of Tarkin's Fist. Tensions between the two immediately escalate as the naval officers and Moffs in command of Tarkin's Fist are unwilling to share the star system they're temporarily stranded in and the Earth is unwilling to surrender to a foreign power. As a result of hostilities with the Empire much of the Earth becomes incredibly xenophobic.

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