The 'Golden Record' sound recordings which were taken aboard the Voyager space probe missions in the 1970s were uploaded by NASA on Monday to SoundCloud, the popular online audio sharing service, giving humans a chance to listen to the sounds originally intended only for alien ears.
The recording comprises greetings in 55 languages, and 19 recordings of 'Sounds of Earth,' including a tractor, Morse code, a chimpanzee and 'the first tools.'
The Golden Record is carried onboard both the Voyager 1 and 2 spacecraft, which launched in 1977 and still returns communication to the Deep Space Network from around 12 billion miles away.
In September 2013 NASA announced that Voyager 1 is the first human-made object to officially venture into interstellar space, having been traveling for about one year in a transitional region of plasma, in the space between stars.
"The spacecraft will be encountered and the record played only if there are advanced spacefaring civilizations in interstellar space," said Carl Sagan, who chaired the committee which selected the content for the Golden Record.
"But the launching of this bottle into the cosmic ocean says something very hopeful about life on this planet."
