Scientists say life on Earth has changed enough since 1977 to update the message
A campaign has been launched to draft a new message to send to the Voyager probes currently travelling billions of miles from Earth.
The Voyager 1 and 2 probes were launched in 1977 with a mission to explore the solar system sending back pictures of planets and their moons.
Now, they are speeding towards interstellar space with one job left - to take a message from humanity as far into space as they can in the hope of encountering intelligent life.
Both probes carry identical "golden records", which contain music, greetings, sounds and even pictures encoded onto them. Their aim is to communicate something of human culture to any extra-terrestrial civilisation.
However, a team of scientists says that humans have moved on from 1977 and life is different enough on Earth to warrant an update to the almost 40-year-old snapshot of life on the planet.
Christopher Riley, professor of science and media at the University of Lincoln's School of Film & Media, is launching a global public call to action on Facebook to crowd-source a short final message which he will invite NASA to send to the memory banks of the voyager probes.
To make it easy to send, the final message will need to be less than 1,000 characters long (about the length of seven tweets).
It would need to be beamed to the twin Voyager spacecraft before their onboard electrical power runs out in the mid-2020s.
Out of power, the two probes will carry on, eventually escape the Solar System to drift through the Galaxy for another billion years.
Prof Riley says: "Before the Voyagers power down, why not add one final message from planet Earth, as a digital postscript to these most remarkable time capsules of humanity?"
The Facebook campaign will collect messages from the public, with the hope of persuading NASA to select one to send to both spacecraft before contact is lost.
Prof Riley says: "There's really no reason why a message can't be written by an impartial representative from the human race, so we're inviting suggestions from anyone who would like to contribute a thought."
Not everyone agrees with the plan, however. Dr Anders Sandberg, a research fellow at Oxford University's Future of Humanity Institute believes the capsules should be left undisturbed.
He said: "I think it's a mistake to update the information. The Voyager probes are time capsules. They were sent off in the late 1970s and reflect the world as it was back then.
"We can't really add much to a message by adding 1,000 letters to it. But it's actually possible to destroy a message or change its meaning.
"If I send you a message and later send a: 'Ha ha, just kidding', I might actually change the meaning of what I've previously sent. I think it's not a good idea to update it - just let them go."