How to Talk to Aliens: Voyager’s Golden Record

Decoding NASA’s message to extraterrestrial civilizations

In 1977 NASA launched Voyager I and II, two space probes with some pretty ambitious goals: to study the Outer Solar System and reach Interstellar Space. This was going to be the first time that we would have the opportunity to be mind blown by close up pictures of Jupiter, Saturn, Uranus and Neptune, and the first time we would see a human made object escape our solar system.

We’re now reaching the end of the probes’ missions, as their power is about to run out. While this means that we will lose all communication with them, their journey is not going to end: they will keep quietly drifting through space, likely for millions and even billions of years.

Now, outer space is mostly that: space. A lot of space. It’s going to take around 40,000 years for the probes to even come close to another star.¹ That being said, in theory there’s nothing stopping the spacecrafts from continuing their journey through our galaxy and eventually passing near a solar system that happens to host an advanced alien civilisation. NASA knew this, and decided that if we’re going to go through all the trouble of hurling two spacecrafts all the way out there where they might come into contact with someone, well we might as well have something to say to them.

They figured: don’t let this opportunity pass. If you’re gonna throw a message in a bottle into the ocean, well put a message in it! So they decided to put time capsules in those bottles.

Jim Bell, Author of “The Interstellar Age”²

A team was assembled with the task of figuring out exactly what to say to these potential aliens, and how. The result was the Voyager Golden Record, a phonograph record containing spoken greetings in 55 different languages, sounds and pictures of the earth and its inhabitants, as well as 90 minutes of music from all around the world.

The record is humanity’s way of saying: “Hello! This is what we look like, this is what we sound like, and here’s some music that we like. Best, Earth”.
We basically made a fancy mixtape for aliens, if that’s not wholesome I don’t know what is.

Left: Golden Record cover, right: the record. Credit: NASA/JPL-Caltech

Of course, there’s the small issue of how exactly you explain to a whole other species how to play a phonograph record, as well as how to extract the images that are encoded in part of that audio. There was also not much time to do it: the record was a bit of a late afterthought, but the launch of the probes had to take advantage of a particular alignments of the planets that only occurs every 176 years³, so it could not be delayed.

We had six weeks to do it. When I talk about the record I think that always draws the biggest gasp: that you had to figure out a way to explain the world to aliens — and by the way, it has to be finished in six weeks.

Jon Lomberg, Golden Record Design Director²

The Golden Record team designed a beautiful cover (pictured above) containing all the instructions needed. It is quite clever and inspiring, so let’s dive into it to try and re-trace the design decisions they made.

Here’s what we need to discuss:

1. How do we communicate numbers to aliens?
2. How do we establish a unit of time that we can use in our instructions?
3. How can we explain how to actually play the record?
4. How could aliens extract the images from the sound in the record?
5. How do we tell them where the probes are coming from?

To fully understand the cover, we’ll need to touch on a range of technical subjects: from binary numbers, to Cathode-Ray Tube Television, to Neutron Stars. This guide was written to be as accessible as possible, so hopefully you can follow along regardless of background (and if a section is too trivial for you, skip ahead!).

Choosing a numbering system

First, we need a way to count: we really can’t do much without numbers. It’s reasonable to expect than an intelligent life form will have invented some way of counting things, but how can we guess which way they picked?

Most of us are used to place-value notation, where each symbol has a different meaning depending on its position in the number string. For example, the two “3”s in the number “33” have different meanings: the first indicates 3x10 while the second is just 3. This is not the only way to represent numbers though: another popular alternative in human history has been sign-value notation, where each symbol always represents the same quantity, and we simply combine them by addition (or, sometimes, subtraction), as we do with Roman numerals.⁴

Whether we use place-value or sign-value, we also need to choose a base for our notation. Most of us use base 10, which in place-value notation means that each location is a power of 10: the rightmost digit represents the 1s, the second from the right represents the 10s, the third the 100s, and so on. But this is an arbitrary choice, likely driven by most of us learning to count on our fingers.⁵ In fact, it is not the only number base used by humans: there are communities that use a base 8 system because they count the spaces in between their fingers or the knuckles of a closed fist, while others even use a base 20 system.⁶ ⁷

So which system should we choose? We want to keep things as simple as possible, so it’s not surprising that the designers of the record opted for place-value notation with base 2, what’s known simply as binary. In contrast with pretty much every other method we know, place-value base 2 allows us to write any number we want using only two symbols, like 0 and 1. This makes it both extremely simple and extremely powerful. In fact, the binary system is so useful that it forms the whole basis of how computers work: the fundamental building blocks of computers are small switches (transistors) that are turned on or off, indicating 1s and 0s. This power and simplicity means that it’s fair to assume that any intelligent civilisation will have used the binary system at some point in their history, or should at least be able to work it out relatively quickly.

Binary works in the same way as the decimal system we’re used to, except it only has 2 symbols instead of 10

Of course — and this will be a recurrent theme — we could be completely wrong. Extraterrestrial life may have developed entirely different counting systems that we can’t even imagine simply because our brains and bodies are wired too differently from them. In a way, this is part of the beauty of this experiment.

Maybe what’s written on it will seem like kindergarden scribbles to them, but they should be able to figure it out. They got some smart minds, or whatever is in their heads… If they even have heads.

Jim Bell²

Interpreting the numbers

Let’s say that we’re aliens who can understand what binary is, and we find the record. How could we go about actually reading the numbers on it? We need to figure out a few things first:

1. We need to realise that some of those groups of symbols are, in fact, binary code
2. Of the two symbols we have identified as binary digits, we need to figure out which one is the 0 and which one is the 1
3. We need to figure out how to read the numbers: left-to-right or right-to-left? Top-to-bottom or bottom-to-top?

We see many groups of small vertical and horizontal lines (︳ and ―), which appear throughout the cover and always as a mix of the two symbols, so we might reasonably guess that this could be binary code. We now have to figure out the symbol for 0 and the one for 1. Most of us are used to Arabic numerals (the standard “0, 1, 2, 3…” digits) so we might be very biased here: it’s quite intuitive for us to think that ︳= 1 and ― = 0, simply because our 1s also look like vertical lines, but we need to remember that this is completely arbitrary. How could we actually infer which is which without this prior knowledge?

Let’s look at one specific section, where we see three particular sets of digits.

One way to take a guess is to note that on the right we have the number ︳︳, which could either represent binary “00” (zero in decimal) or “11” (three in decimal). However, writing zero as “00” would be redundant, as it could equally be written as just “0”. Additionally, the number on the left is just ︳, which would again be “0”. What would be the reason for writing zero as “0” (︳) in one place and “00” (︳︳) in another? These are pretty good clues that it might be more reasonable to assume that ︳= 1 and ― = 0.

Having established what the symbols likely represent, how can we now figure out which way we should read them? This turns out to be pretty easy. First, we need to note that when writing in place-value notation, leading 0s are superfluous. For example: the number three is written in binary as 11, but it could technically also be written as 011. This is not wrong, and there are cases where we might want to do that, but in general that first 0 is redundant, so it makes little sense to add it, particularly in a manual to aliens.

Now let’s look at the following number:

If it was meant to be read right-to-left, it would start with two leading 0s, which is redundant. Equally, if it was to be read bottom-to-top, it would start with several leading 0s. So, without knowing anything else, our best guess is that the numbers should be read left-to-right and top-to-bottom.

We now have a system to write numbers and we’re confident enough that an intelligent species could work it out, hooray! We’re past the most tedious hurdle, now we get to the juicy part.

I tried to think: “How would an alien look at this picture?” There are always two requirements: you wanted things to be as easy as possible to understand, but you also wanted to have as much information as possible in each picture, and those two requirements are kind of at odds.

Jon Lomberg²

Finding a universal unit of time

If we’re lucky, our aliens can now read the numbers on the cover. Of course, numbers on their own often don’t mean much. As we’ll see, in our case we will frequently need to give instructions that involve time: how fast to turn the record, for how long, etc. This means that we need a unit of time, and this is where things start getting a bit tricky. How can we possibly communicate something like this? Most of us are used to measuring time in seconds/minutes/hours/days/years, all units that are fundamentally linked to our own planet. But whoever finds the record is unlikely to know that it came from Earth, and we have no way of knowing how long a day or a year is for their planet.

So we need to find something more universal (literally). It makes sense to try and find something so common that it’s almost guaranteed that an advanced intelligent life form will have discovered it and should be able to recognise it. This is where hydrogen comes in. Hydrogen is the most common element in the universe, making up around 75% of all normal matter⁸ (most of the universe seems to actually be made of “dark”, ie not “normal”, matter, but we don’t know much about it, so we can’t really use it). For example, hydrogen makes up around 90% of the atoms of both our sun and Jupiter.⁹ ¹⁰

A hydrogen atom is made of a single electron and a single proton, so a simple diagram of it should be easy to recognise:

A simple diagram of a hydrogen atom: one central circle indicating the proton, a thin external circle indicating the trajectory of the electron as it spins around the proton, and a third solid circle indicating the electron itself.

How can we get a time unit from hydrogen? First of all, we need to know that elementary particles (like electrons, neutrons and protons) have a property called spin. Confusingly, this does not come from any spinning motion. Elementary particles act like tiny magnets, and their spin is a property linked to the orientation of their magnetic field. The discussion could get quite complicated and technical here, but for our purposes all that matters is that particles have a property we call “spin”, which we can measure as being in one of two directions: “up” and “down”.

Since hydrogen atoms have one proton and one electron, we can find one of two situations: either the proton and electron have the same spin (ie both up or both down), or they have opposite spin. These two forms are not exactly equal: when the proton and electron have the same spin, the hydrogen atom is in a slightly “excited” state, meaning it has a little bit more energy. Eventually, however, this more excited atom will transition to its lower energy state: the spin of the electron will flip and become opposite to the spin of the proton in what is known as a “spin-flip” transition.¹¹ During this transition, the small amount of extra energy previously held by the atom is released as radiation with a characteristic period (the time it takes for a wave to complete one oscillation) of 0.7 nanoseconds. If we can find a way to represent the hydrogen spin-flip transition, we can use 0.7ns as our unit of time!

We first need to represent hydrogen. As we saw before, we could simply draw the outline of a larger circle with two smaller solid circles representing the electron and proton. However, this doesn’t allow us to show the spin of the two particles. Instead, we need to represent the particles with a shape that has a direction, so we could for example use small arrows instead of circles.

In the bottom right corner of the record we find exactly this, except that instead of arrows the designers used simple lines with a circle at one of their ends:

In this diagrams there are two hydrogen atoms: one where the proton and electron have the same spin, the other where they have opposite spin. The transition is represented as a line connecting the two atoms: this establishes that one unit is equal to the characteristic period of the hydrogen spin-flip transition, 0.7ns.

Playing the record

Now that we have a way of counting and a unit of time, we can attempt to explain how to play the record.

There are two key pieces of information we need to convey:

1. The record needs to be turned such that the stylus moves along its groove, following the spiral from the edge of the record all the way to the centre.
2. The record should turn at a certain speed.

In the top left of the cover we see a top view of the record with a stylus placed in the correct starting position. A stylus is included on the spacecraft, so that should be easy to recognise. Unfortunately, there’s no easy way to explain “You have to turn this bit!”, but we can try. The tip of the provided stylus will match the width of the grooves on the record, so hopefully this will help to perfectly place it in its starting position, and even suggest that the stylus should be made to follow the groove along the record.

All along the outer edge of the record we see the binary number 100110000110010000000000000000000, or 5113380864 in base 10. This is not written in the standard left-to-right, top-to-bottom way as other numbers on the record, but — following the same logic as before — there is only one way it can reasonably be read (as the other would result in several leading 0s). Hopefully, having written the number along the entire edge of the record will give a hint at its meaning: the duration of one rotation. Using the unit we defined before we get 5113380864 x 0.7 nanoseconds = 3.6 second. So one rotation should take 3.6 seconds.

Below the top view of the record, we see another diagram representing a side view of it, again with the stylus in the starting position. Below that, two long vertical lines delimit the starting position of the stylus (the edge of the record) and the final position (the center), a further hint to say “You need to find a way to move this thing from here to there”. Within the two long lines, a binary number indicates how long it should take for the stylus to go from one position to the other, ie: how long it should take for a whole side of the record to play.

The number is 1000010110000000000000000000000000000000000, or 4587025072128 in base 10. So we get 4587025072128 x 0.7 nanoseconds = 3210.9 seconds = ~54 minutes

Hopefully, with some effort, our aliens can figure out that they need to turn the record at 3.6 seconds per rotation for 54 minutes, making sure that the stylus follows the groove on the surface so that it moves from the edge of the record all the way to the centre.

If they have gotten this far, they will now be able to play the audio part of our message! They’ll be able to listen to the sounds of our planet: our voices, music, nature, animals, cities. Maybe some of those sounds will be similar to ones they’re familiar with: if a planet has liquid water, there’s a chance they will recognise the sound of our waterfalls. Others might be completely new to them, like our voices or our laughter. It’s fun to try and guess which sounds have the potential to be recognised. Will the noise of the motors in our cars be completely foreign to them, or will it resemble something they also use on a daily basis?

There are many reasons to think that aliens might have music, and even that their music might be similar enough to ours that they could understand it and like it. The main reason for that is a lot of things about music are based on the physics of how sound works: when a guitar string vibrates, you have these harmonics and overtones, a series of notes that the string makes. That’s the same anywhere in the universe. And a lot of how we harmonise and how we make music is based on things like those intervals from a vibrating string, so music isn’t something completely arbitrary. The way we try to pattern the music — that may be unique to us.

Jon Lomberg¹²

Decoding the images on the Golden Record

Having successfully learned to play the audio in the record, there is still much left to do to be able to extract the images that are encoded in a part of that audio. Before diving into analysing more of the diagrams, let’s take a moment to go over how exactly one can convert images into sound.

Turning images into sound

By now, most of us are familiar with digital images being made of pixels: the small single-colour squares that you can see if you zoom enough into any image:

This concept is useful, because it means we can take any picture, divide it into many small squares, and assign some value to each square based on its colour. For simplicity, let’s stick to black and white images. We can create a linear scale of values from black to white (known as grayscale):

The values of grayscale represent the “intensity” of a pixel, so that black is 0 (absence of light, no intensity) and white is 1 (maximum intensity).

Now let’s take as an example the simple black and white image below: a square with three stripes (black, dark gray, and light gray) on a white background.

Let’s say we split this into 5x5 “pixels”. We can now assign to each pixel a certain grayscale value, then unwrap the image (for example line by line), and we obtain a simple sequence of numbers. So we can represent our original image as “1 1 1 1 1 1 0 0 0 1 1 0.3 0.3 0.3 1 1 0.6 0.6 0.6 1 1 1 1 1 1”. Given this sequence, if we know the length of each “subsequence” (that is, each row), we can recreate the original image.

Our problem has now become “How do we turn a sequence of numbers into sound?”. There is no one way to go about this: for example, we could assign a different type of sound to each number, but that could get quite complicated to explain. We want to find the simplest way to do this. How about using volume? So far we have decided that 0 = no light intensity and 1 = maximum light intensity, we can easily transfer this to sound: 0 = no sound, 1 = maximum volume. This allows us to turn our sequence into a simple signal.

If I now were to send you an audio recording where I vary the volume following this pattern, as long as I tell you how long each subsequence is, you should be able to recover the original image.

To be precise, this is a simplified way of representing an audio signal, and not fully accurate. You may have seen audio waveforms like this:

A screenshot of an mp3 opened in Audacity

We see that the signal actually goes from -1 to 1 instead of from 0 to 1. This is because audio signals are actually bipolar, meaning they contain both positive and negative values: a constant 0 indicates silence, and the further away the signal goes from 0 (either in the positive or negative direction), the louder the sound. To explain why this is we would need to get into how sound works, which is not that important for our purposes. All that matters is that we can apply the same concept as before, just on a different scale.

Now that we have a way to turn images into sound, we need to explain to our aliens how to go the other way around to recover the images.

Turning sound into images

The aliens now have the audio we put on the record, but how can we tell them that part of that audio actually encodes images? Something we need to know is that NASA’s clever folks put a loud “beep” before the start of each image. This means that after all the music and earth sounds are finished, the record will start playing a sequence of intermittent (and possibly annoying) beeeeep. You can listen to it here (the beeps start around 30 seconds in):

Now, on the top right of the cover we see this diagram:

This is representing an audio waveform, specifically the start of the waveform of one image. The zig zag pattern on the left is what the waveform for a “beep” looks like, and the rest is, well, some kind of sound. This doesn’t seem awfully specific, but if anyone plays the record and looks at its waveform, they should recognise that at some point a pattern appears: beeep, some sound, beeep, some other sound, beeep... That is, a part of the audio is divided into several sections (our images) that are separated by the “zig zags” / beeps.

Screenshot of the waveform a part of the image section. Due to the noise that is naturally introduced during the production and then playing of the record, the signal is obviously not as clean as the diagram, but we can nonetheless easily recognise the zig zag pattern indicating that a new image is about to start, followed by the beginning of the actual signal.

From the diagram we can then see that each image section is made up of several subsections: the diagram shows the first three, marked above by “1”, “10”, and “11” (1, 2, and 3). Below the first subsection, two lines delimit its start and end, and within them a binary number indicates its length: 101101001100000000000000, or 11845632 in decimal. 11845632 x 0.7 nanoseconds = 8 milliseconds. Therefore each subsection of the image is 8 milliseconds long.

Now, to make the next diagrams quicker to understand we need to take a little digression and talk about Cathode-Ray Tube (CRT) Television, ie: the type of television that was still in use in the 70s, when the two Voyager probes were launched.

Credit: PJ Gal-Szabo

These televisions are built around a “cathode-ray tube”, which contains an “electron gun”, which… well, shoots electrons. The electrons hit a coating behind the screen containing phosphor, a substance that emits light when hit by certain radiations.¹³ ¹⁴ In essence, the electron gun sends a beam of electrons towards a point on the screen making it light up. Earlier we talked about grayscale and how black = no light intensity, while white = maximum light intensity. In the same way, the screen will show a white dot where it’s hit by a full-intensity beam, and black where it isn’t. We can then vary the intensity of the beam to create different shades of gray, giving us the ability to display black and white pictures.

Credit: ScienceFacts

Note that the electron gun shoots only one beam of electrons, which will hit a precise spot on the screen. The reason we can see a whole image instead of a single dot is that the beam is moved across the entire screen faster than our eyes can catch it, giving us the illusion of a full picture.

A slowed down rendition of the beam of a CRT TV

The beam is moved from left to right to draw a line, then quickly moved back to the left but slightly lower down to draw the next line. The beam’s trajectory is then a zig zag patterns from left to right and top to bottom:

Now let’s go back to the record cover. We see these two diagrams:

Hopefully, they should now look somewhat familiar: they’re essentially representing how a CRT television would draw images, except that the lines are drawn vertically instead of horizontally. In the top diagram we see the three subsections from earlier, again marked “1”, “10”, “11”. The diagram indicates that each subsection is a line, and that they should be arranged vertically: we take the first one and draw it top to bottom, then go back up to place the second one, and so on. This is made more clear in the second diagram: the rectangle indicates the full image, and we see that the three subsections/lines from before are now placed left-to-right from the left edge of the image (again, marked by 1, 10, 11). Towards the right edge, we see a final line with the number 1000000000 (512), indicating that there are a total of 512 lines in each image.

Obviously, we got to this point after learning about CRT TV, and it would be quite a stretch to assume that aliens will have developed that same technology. However, this was just a shortcut to make the explanation quicker. Given enough time, they should be able to work things out without knowing anything about CRT TV. In fact, there are examples of people who have independently decoded the record without needing access to (or knowledge of) 70s technology.¹⁵

There’s one more detail about the top diagram we haven’t discussed: the three pairs of circles that appear on the lines. We can note that the pairs are staggered: if we drag one line over an adjacent line, the circles from one line will fit in between the circle of the other.

I assume (and NASA’s website seems to back this up¹⁶) that this implies that the pictures are encoded in a staggered way, which essentially means that half of the information is missing, but can be reconstructed from the information that is present.

Example of “staggering” an image and then reconstructing it by replacing the missing pixels with the average of the adjacent colours.

Our aliens should now finally have everything they need to decode the images! There’s one more diagram related to this section:

What does this mean? Well, if we correctly decode the images, the first one to come out is…

Image decoded by Ron Barry¹⁵

The diagram essentially serves as a calibration tool: if you get a nice circle as your first image, you’re doing things right!

The pulsar map

We’re nearly there, only one diagram left to go. We’ve explained how to play the record and decode the images on it, the only thing missing from this nice if slightly complex message is a sign-off of some sort. After all, who is this from? We need some way of saying “Kind Regards, Earth”. The record designer decided to do this by including a map to indicate the position of our solar system in our galaxy, the pulsar map.

First of all, what is a pulsar? When a star goes supernova (explodes) its core collapses into a “neutron star”. This can’t be overstated: neutron stars are absolutely insane objects. They’re relatively small, with a diameter of around 20km, and yet they have a mass that is nearly 1.5 times the mass of the sun (which has a diameter of 1.4 million km).¹⁷ Imagine compressing the sun into a spot roughly the size of Amsterdam. When you have something that is that dense, all kinds of weird, amazing things start to happen. One of which is what leads some (but not all) neutron stars to being called pulsars.

An artist’s illustration of a neutron star. Credit: ICRAR/University of Amsterdam¹⁸

A pulsar is a neutron star which emits two opposite beams of light from its magnetic poles. The key interesting thing for our purposes is that a pulsar is spinning, but along a different axis from the axis of its beams. This means that the beams are not constantly pointing in the same direction, but spinning around, a bit like a galactic lighthouse. The earth is on the path of the beams of some pulsars in our galaxy, but as the beams are constantly moving, sometimes they hit us and sometimes they don’t. The result is that from our point of view, pulsars look like blinking stars, turning on and off with a specific frequency.

A pulsar spins around one axis (the black line), and has two light beams that are directed along a different axis, so that the light beams are always moving around.

What’s useful for our purposes is that each pulsar has its own distinctive pulse rate, meaning we can use them as reference points to give directions within our galaxy. This is how we get to the pulsar map.

The focal point towards the left (the point that all lines converge to) is our sun, the point all the way to the right is the center of our galaxy. All lines apart from the one connecting the sun and the galactic center are accompanied by a binary number. These are 14 known pulsars visible from Earth: the binary numbers indicate their pulse rates (their signatures), and the lines connecting them to the centre indicate the relative distance and direction of each of them from the sun. Obviously, space is three dimensional, and this is a two dimensional map, which could be a problem. Thankfully, the majority of planets and stars in a galaxy lie roughly on the same plane (the galactic plane), so that from the “side” galaxies look kind of flat.

A “side view” of our galaxy. Credit: NASA¹⁹

This means that it is quite intuitive to take our two dimensional surface to be the galactic plane, so that our map can essentially be considered a “top view” of our galaxy. Then all we need is a way to say how far above or below this plane each pulsar is, so that we can accurately describe its location.

We can notice that each pulsar line has a tick mark towards the end of the line. This is used to give the distance of the pulsar from the plane.²⁰ The mark doesn’t specify whether it is above or below the plane, but with the given information on all these different pulsars, the location of each should become obvious. However, we’re actually not completely confident about the exact distance of all pulsars, so for the ones where there’s some doubt the designers added a little break in the line.

And that’s it! If our (hopefully friendly) aliens are able to identify the pulsars, they should now be able to work out our approximate location in the galaxy.

I find this map extremely beautiful, but if the thought of strange species from other worlds knowing exactly where we live makes you nervous, relax: it turns out that while not technically wrong, the map is most likely useless. Pulsars were discoverd in 1967, so they were still a relatively new subject of study when Voyager II was launched in 1977. With time, we have realised that there are likely to be a billion neutron stars in the Milky Way, many of which will be pulsars.²¹ Even setting aside the low likelihood of anyone finding the Voyager probes anytime soon, expecting aliens to figure out exactly which 14 pulsars we used to create the map is quite optimistic.

Hope everyone’s well. We are thinking about you all. Please come visit us when you have time.

Mandarin Chinese Greeting on the Golden Record

Some final thoughts

Imagining an alien understanding all those diagrams with no help might seem far fetched. However, whoever finds the record will hopefully be interested enough in it to spend a good amount of time and resources into trying to decipher it. Certainly longer than it takes to read this story, I would hope.

Something else to consider is that it’s highly unlikely that the Voyager probes will simply land on some random alien planet. Once again: space is mostly space. A more realistic scenario is that the spacecrafts will pass by several solar systems, and will only be intercepted when a planet in one of those solar systems has a civilisation that is advanced enough to be able to notice them and — most importantly — go out and get them. This means that whoever does find them has to be pretty good at science and engineering. It’s not unrealistic to expect that we’ll share some commonalities, at least in our mathematical and scientific thinking.

In a way, all of this is beside the point. No matter what happens, whether somebody finds the record or not, we can still be proud of having sent our signature into the universe, a testament to our relentless curiosity and ingenuity, our creativity and hopefulness. A little time capsule of all the best parts of being humans.

People throw bottles in the ocean, and most of them are never found, but sometimes they are, so you always hope. But even if they’re not found, the fact that something that we made, that has some of the best of our music, some of our most beautiful scenes on earth… — that will survive, bearing witness that we were here. Even if it’s never found, that’s almost more thrilling. Thousands and millions and billions and maybe even trillions of years from now, something that came from earth in the 20th century is still there.

Jon Lomberg¹²

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