Imagine meeting a real-life alien.
Whether itโs the classic green, large-headed creature we see in movies, or the blue, centaur-like Andalites of childrenโs sci-fi, picture yourself meeting them and having the task of introducing yourself. Who and, more crucially, what exactly are you?
Itโs not as easy as filling out a LinkedIn profile. Basic personal information like your full name and educational attainment, for example, may not hold much meaning to someone who grew up light-years away and has no idea what an HR manager is.
You can always talk about biology, what makes our cells work and how organs work together, but that doesnโt quite capture who we are. Neither does it help explain to aliens why we humans can look so different on the outside, or why we behave the way we do.
You can even talk about the culture of your people, one of many across the globe, as well as your interests. But then again, what does all that even mean to someone who doesnโt understand the cultural significance of Lady Gaga or the triumph of the #FreeBritney movement?
Trying to explain who and what we are is something that scientists have sought to do throughout the past couple of centuries.
More recently, everyday folks have tried to grapple with this idea in subreddits like r/humansarespaceorcs, where people take on the interesting exercise of stepping back from humanity and all we know as part of it. From there, we can start trying to see ourselves from the eyes of someone from an entirely different galaxy โย with its own physiology, cultures, and intergalactic knowledge.
Are We Alone in the Universe?
Before we began trying to reach out to aliens, humanity first had to contend with the question of whether or not they exist.
For instance, before Jesus came around, ancient philosophers like Epicurus and Anaximander talked about how the universe is likely home to many different planets, and that many of these planets might just support life. Though we know that the first half of that is a fact (the list of 2021โs exoplanet discoveries is a pretty exciting one), the second half is still up in the air or, well, the vacuum of space.
Epicurus and Anaximanderโs ideas took a while to be properly appreciated, at least in Europe, because the likes of Plato and Aristotle (names most of us are more familiar with), argued that there couldnโt be any other worlds. However, medieval Islamic scholars like Muhammad al-Baqir and Fakhr ad-Din ar-Razi preached about a cosmic pluralism similar to Epicurus and Anaximander.
By the 16th century, the idea that the planets go around the sun โ not the other way around โ took hold, and kicked off the Copernican Revolution, so named after Nicolaus Copernicus. Once people realized the Earth wasnโt the center of the solar system and instead was just one of several planets revolving around our sun, it became much easier to think about other planets around other suns, with other possible forms of life on them.
Since then, many thinkers have proposed ways to send out messages to those possible life forms. Without the benefit of spacecraft, early 19th century astronomers werenโt yet thinking about introducing us in all our complexity; they just wanted to let aliens know that we exist, and weโre here.
One of these people was the Austrian astronomer Joseph Johann Von Littrow. The story goes that he once proposed that trenches be dug in vast, geometric patterns across the Sahara desert. These trenches could then be filled with water, and then kerosene, which people could light ablaze in order to send a signal to whoever might be out there to see.
Another idea from that era, this time from German mathematician Carl Friedrich Gauss, went a step further. Gauss believed in the possible existence of โlunarians,โ or creatures on the moon.
(This was, interestingly, a popular idea at the time, so much so that a New York newspaper published a series of articles on life on the moon โ what we might call today as fake news โ in the 1830s.)
Gauss wanted to show these lunarians that not only do we exist, but that we also understand basic math.
So, he proposed to cut down trees in large areas of the Siberian forest to create certain shapes that could be seen from the moon. And these shapes? Our high school best friend (or tormentor), the right triangle of the Pythagorean theorem.
Thatโs right. He wanted to show aliens that we know our a2 + b2 = c2.
If those ideas made you sweat, either from the math involved or the carbon in all that kerosene-burning and tree-cutting, then the good news is that neither of these ever came to fruition.
In fact, it wasnโt until the 20th century that we truly began sending out messages about who we are to life outside of earth โ thanks largely to radio technology.
What Weโve Sent to Aliens
โMir,โ โLenin,โ and โUSSRโ
The first credited attempt to reach out to aliens via radio was in 1962, when Soviet scientists aimed a radio transmitter at the planet Venus. Through Morse code, they introduced humanity using three words: โMirโ (a Russian word that means both โpeaceโ and โworldโ), โLeninโ (as in, Vladimir, the Russian revolutionary), and โUSSR.โ
Known as the Morse Message, itโs the first radio broadcast designed to reach aliens, though it was also a kind of test for their brand-new planetary radar. The signals bounced back to Earth in just over four and a half minutes, and are currently in transit to the star HD 131336, which is in the Libra constellation.
Drawings of DNA, a Human, Our Solar System, and a Radio Telescope
In 1974, the Arecibo radio telescope in Puerto Rico marked its remodeling by sending out whatโs known today as the Arecibo Message, which carries basic information about the earth and humanity.
The signals were sent to star cluster M13, but werenโt a serious attempt to converse. Instead, it was meant as a demonstration of what technology could do.
The message was sent in binary code, and when properly translated, depicts the following:
- Numbers one to ten;
- Atomic numbers of elements that make up our DNA;
- A graphic of the double-helix structure of our DNA;
- A drawing of a human being;
- A graphic of the Solar System; and
- A graphic of the Arecibo radio telescope.
The 1,679 bits of data it took to send this message is a shot in the dark. For starters, the low resolution of the resulting image makes it unlikely for aliens to make sense of whatโs in it โ and thatโs if they find the code. Because the M13 is 25,000 light-years away, the cluster wouldโve moved by the time the signals make it to their destination.
Sounds and Pictures of the World
Itโs not just radio signals, either.
In 1977, Voyagers 1 and 2 were launched to explore space. In 2012, Voyager 1 made it past our solar system and into interstellar space, followed by Voyager 2 in 2015. Aside from sending back information about the greater galaxy, these spacecraft also carry a Golden Record, which works kind of like a time capsule for extraterrestrials.
The record contains over a hundred images and natural sounds from earth, like wind, birds, whales, and the surf, as well as different cultures. It also contains over 55 ways to say hello in different languages, as well as messages from governments.
Music and Art From Teens
In 2001, a group of Russian teens helped select the content that came to be known as the Teen Age Message, which was sent from the Yevpatoria Planetary Radar to six different stars. Each message had three parts:
- A sounding signal that imitates transmissions from our sun, so that aliens might know where the message is coming from;
- Analogue music recorded on an electrical instrument called the theremin, comprising seven musical compositions; and
- Digital data similar to the Arecibo message, but containing greetings in Russian and English, as well as drawings.
The signals are described as the “First Theremin Concert for Extraterrestrials,โ with the closest target set to receive them in July 2047.
A Beatles Song
The Theremin Concert was the first music we sent out to aliens via radio, but it certainly wasnโt the last.
In February 2008, NASA sent out the song Across the Universe by the Beatles via the Deep Space Network’s Madrid Deep Space Communication Complex. The radio message was part of the 40th anniversary of the songโs release, as well as the 50th anniversary of NASA itself.
Beatles historian Martin Lewis even encouraged fans to play the song while the recording was being beamed.
Though weโre not entirely sure what musical genres aliens would prefer, thereโs something about the idea an alien listening to, โLimitless undying love which shines around me like a million suns, / It calls me on and on across the universe,โ that makes you think about what it means to be a human.
A Doritos Commercial
Yup, you read that right.
In June 2008, Doritos beamed an ad entitled Tribe, which got the most votes among the British public, via the EISCAT European space station in the Arctic Circle. Produced in partnership with the University of Leicester, the adโs destination is the Ursa Major or Great Bear Constellation, which is 42 light-years away.
A Time Capsule
2008 was a busy year in trying to communicate with aliens, it seems. In October of that year, Ukraine’s State Space Agency sent out a digital time capsule that contained over 500 messages collected through Bebo, a social networking site. These messages, called “A Message from Earth,” were selected from a pool of over half a million people, which included celebrities and politicians.
The target planet was Gliese 581c, and the message is expected to arrive in early 2029 โ just seven years from now.
An Invite to a Star Trek Opera
Trekkies are a pretty innovative bunch. Aside from helping create fanfiction as we know it, they also created the worldโs first Klingon opera, staged in Holland back in 2010.
The production went all out โ even sending invites to Qo’noS or, at least, the general direction of where QoโNoS would be in real life.
What Weโve Gotten Back
So after all that, you might notice that aliens havenโt exactly come knocking on our atmosphere for a taste of Doritos or a seat at the Klingon opera. And in truth, we havenโt really heard much from aliens, at least not in a way thatโs been verified by the scientific community.
This silence, despite the vastness of the universe and the strong possibility that thereโs more here than just us, is whatโs called the Fermi Paradox. Maybe our messages havenโt made much sense to them, or perhaps they havenโt had the chance to send back a response.
There are, however, a couple of signals scientists are still studying. One is called the Wow! Signal, detected in 1977, which remains our strongest case for alien radio transmissions. But thereโs also a mysterious set of signals detected from Proxima Centauri, the star closest to our own, that scientists are still investigating.
Whether these are real aliens trying to respond is still up for debate. But if you were to send out a signal to them about who we are all these years since Soviet scientists opened the door for radio transmissions, what would you say?