A pop­u­lar thought exper­i­ment asks us to imag­ine an advanced alien species arriv­ing on Earth, not in an H.G. Wells-style inva­sion, but as advanced, bemused, and benev­o­lent observers. “Wouldn’t they be appalled,” we won­der, “shocked, con­fused at how back­ward we are?” It’s a pure­ly rhetor­i­cal device—the sec­u­lar equiv­a­lent of tak­ing a “god’s eye view” of human fol­ly. Few peo­ple seri­ous­ly enter­tain the pos­si­bil­i­ty in polite com­pa­ny. Unless they work at NASA or the SETI pro­gram.

In 1977, upon the launch­ing of Voy­ager 1 and Voy­ager 2, a com­mit­tee work­ing under Carl Sagan pro­duced the so-called “Gold­en Records,” actu­al phono­graph­ic LPs made of cop­per con­tain­ing “a col­lec­tion of sounds and images,” writes Joss Fong at Vox, “that will prob­a­bly out­last all human arti­facts on Earth.” While they weren’t prepar­ing for a vis­i­ta­tion on Earth, they did—relying not on wish­ful think­ing but on the con­tro­ver­sial Drake Equa­tion—ful­ly expect that oth­er tech­no­log­i­cal civ­i­liza­tions might well exist in the cos­mos, and assumed a like­li­hood we might encounter one, at least via remote.

Sagan tasked him­self with com­pil­ing what he called a “bot­tle” in “the cos­mic ocean,” and some­thing of a time cap­sule of human­i­ty. Over a year’s time, Sagan and his team col­lect­ed 116 images and dia­grams, nat­ur­al sounds, spo­ken greet­ings in 55 lan­guages, print­ed mes­sages, and musi­cal selec­tions from around the world–things that would com­mu­ni­cate to aliens what our human civ­i­liza­tion is essen­tial­ly all about. The images were encod­ed onto the records in black and white (you can see them all in the Vox video above in col­or). The audio, which you can play in its entire­ty below, was etched into the sur­face of the record. On the cov­er were etched a series of pic­to­graph­ic instruc­tions for how to play and decode its con­tents. (Scroll over the inter­ac­tive image at the top to see each sym­bol explained.)

Fong out­lines those con­tents, writ­ing, “any aliens who come across the Gold­en Record are in for a treat.” That is, if they are able to make sense of it and don’t find us hor­ri­bly back­ward. Among the audio selec­tions are greet­ings from then-UN Sec­re­tary Gen­er­al Kurt Wald­heim, whale songs, Bach’s Bran­den­berg Con­cer­to No. 2 in F, Sene­galese per­cus­sion, Abo­rig­ine songs, Peru­vian pan­pipes and drums, Nava­jo chant, Blind Willie Johnson’s “Dark Was the Night” (play­ing in the Vox video), more Bach, Beethoven, and “John­ny B. Goode.” Chal­lenged over includ­ing “ado­les­cent” rock and roll, Sagan replied, “there are a lot of ado­les­cents on the plan­et.” The Bea­t­les report­ed­ly want­ed to con­tribute “Here Comes the Sun,” but their record com­pa­ny wouldn’t allow it, pre­sum­ably fear­ing copy­right infringe­ment from aliens.

Also con­tained in the space­far­ing archive is a mes­sage from then-pres­i­dent Jim­my Carter, who writes opti­misti­cal­ly, “We are a com­mu­ni­ty of 240 mil­lion human beings among the more than 4 bil­lion who inhab­it plan­et Earth. We human beings are still divid­ed into nation states, but these states are rapid­ly becom­ing a sin­gle glob­al civ­i­liza­tion.” The mes­sages on Voy­agers 1 and 2, Carter fore­casts, are “like­ly to sur­vive a bil­lion years into our future, when our civ­i­liza­tion is pro­found­ly altered and the sur­face of the Earth may be vast­ly changed.” The team chose not to include images of war and human cru­el­ty.

We only have a few years left to find out whether either Voy­ager will encounter oth­er beings. “Incred­i­bly,” writes Fong, the probes “are still com­mu­ni­cat­ing with Earth—they aren’t expect­ed to lose pow­er until the 2020s.” It seems even more incred­i­ble, forty years lat­er, when we con­sid­er their prim­i­tive tech­nol­o­gy: “an 8‑track mem­o­ry sys­tem and onboard com­put­ers that are thou­sands of times weak­er than the phone in your pock­et.”

The Voy­agers were not the first probes sent to inter­stel­lar space. Pio­neer 10 and 11 were launched in 1972 and 1973, each con­tain­ing a Sagan-designed alu­minum plaque with a few sim­ple mes­sages and depic­tions of a nude man and woman, an addi­tion that scan­dal­ized some puri­tan­i­cal crit­ics. NASA has since lost touch with both Pio­neers, but you may recall that in 2006, the agency launched the New Hori­zons probe, which passed by Plu­to in 2015 and should reach inter­stel­lar space in anoth­er thir­ty years.

Per­haps due to the lack of the depart­ed Sagan’s involve­ment, the lat­est “bot­tle” con­tains no intro­duc­tions. But there is time to upload some, and one of the Gold­en Record team mem­bers, Jon Lomberg, wants to do just that, send­ing a crowd­sourced “mes­sage to the stars.” Lomberg’s New Horizon’s Mes­sage Ini­tia­tive is a “glob­al project that brings the peo­ple of the world togeth­er to speak as one.” The lim­i­ta­tions of ana­log tech­nol­o­gy have made the Gold­en Record selec­tions seem quite nar­row from our data-sat­u­rat­ed point of view. The new mes­sage might con­tain almost any­thing we can imag­ine. Vis­it the pro­jec­t’s site to sign the peti­tion, donate, and con­sid­er, just what would you want an alien civ­i­liza­tion to hear, see, and under­stand about the best of human­i­ty cir­ca 2017?

via Ezra Klein/Vox

Relat­ed Con­tent:

Carl Sagan Presents a Mini-Course on Earth, Mars & What’s Beyond Our Solar Sys­tem: For Kids and Adults (1977)

NASA Releas­es a Mas­sive Online Archive: 140,000 Pho­tos, Videos & Audio Files Free to Search and Down­load

NASA’s New Online Archive Puts a Wealth of Free Sci­ence Arti­cles Online

Josh Jones is a writer and musi­cian based in Durham, NC. Fol­low him at @jdmagness