The opening scene of Robert Zemeckis's Contact—adapted from Carl Sagan's novel of the same name—offers one of the more breathtaking cinematic explanations of how lightyears work. As the film pulls away from the planet, radio waves (which move at the speed of light) broadcast what you might hear on Earth to the planets further and further out. In the film, broadcast transmissions leaving the planet become a major plot point in mankind's first contact with a race from the stars. But over at the site Lightyear.fm, they ask another question: What if the aliens who got our radio waves just, you know, rocked out to it?
That's the premise behind the site, which was created by a quartet of viral web vets—former BuzzFeed creative directors Mike Lacher and Chris Baker, TomHaverfoods.com creator Brian Moore, and computational designer Mike Chernov. The interactive site lets you specify a distance—10 to 110 lightyears away—and then plays you a selection of the radio hits that the creatures living near, say, v1216 Sagittarii are jamming right now (they just got "Sexyback," incidentally, and are presumably psyched about it). Going further out, you can check out other tracks that are hot throughout the galaxy—over on Arcturus, for example, they're grooving to KC and the Sunshine Band and the Bee Gees, and desperately waiting for punk rock to happen, while on Alpha Serpentis, they've got Fats Waller and Bob Crosby and his orchestra to keep 'em going, a jazz-era soundtrack that any long-lived species out there are going to find very familiar if they spend much time playing the Fallout franchise (which, if they're digging earth's music, they're probably eager to try).
The site's math is pretty easy to figure out—30 lightyears from here, the radio waves (if they don't become too diffuse to pick up) would be carrying music that was popular 30 years ago—but the audio and visualization of what that would look and sound like is fascinating, as are the chances to associate the distance from earth of various stars with something concrete, like "Satisfaction" by the Stones. In any case, one thing is clear: the aliens cranking up earth hits 20 light years away are gonna get pretty sick of hearing "Uptown Funk" at their weddings in the summer of 2035.