Hey aliens, here’s our new album! How do you follow up a 50-year-old record that’s hurtling through space?

The Golden Record - launched in 1977 on the Voyager space probes - contained everything from Chuck Berry to Chinese dialects and the sound of humpback whales. But what would we put on it today?

It's almost 50 years since one of the strangest records ever made was launched - not into the pop charts but into the farthest reaches of outer space. Known as the Golden Record, this 12-inch, gold-plated copper disc was an album compiled by astronomer Carl Sagan featuring everything from classical music and spoken-word greetings to the sounds of nature and a blast of Chuck Berry's Jonny B Goode. Humans could enjoy it, of course, but they weren't the target audience. Rather, a copy was placed on Voyager 1 and 2, the two space probes launched in 1977, in the hope that they would one day be discovered and listened to by an alien life form.

The Golden Record came with various diagrammatic instructions on how to play it correctly. But as to what aliens might make of Bach's Brandenburg Concerto, the sounds of humpback whales and a greeting in the Chinese dialects Wu, we will never know. Both Voyager probes are still intact, currently hurtling through the Kuiper belt in interstellar space, but we are likely to lose contact with them in around a decade's time. This means we will miss the Golden Record's first realistic chance of being discovered - when it's expected to pass within 1.6 light years of the star Gliese 445 in 40,000 years' time.