A new search for intelligent alien life using two of the world’s most powerful telescopes has been launched by leading scientists including Professor Stephen Hawking.
The telescopes will scour one million of the closest stars to Earth for faint signals thrown out into space by intelligent life beyond our own world.
Scientists taking part in the $100 million (£64 million) initiative will also scan the very centre of our galaxy along with 100 of the closest galaxies for low power radio transmissions.
In a second initiative, an international competition will be held to generate messages representing humanity and planet Earth, which may one day be sent to alien civilisations.
The new search for intelligent life, which promises to cover 10 times more of the sky than previous attempts, is backed by Russian billionaire entrepreneur Yuri Milner, who set up the Breakthrough Prize for scientific endeavours.
The attempt to find signs of alien life, which has been named the Breakthrough Listen Initiative, will draw on the expertise of leading scientists, physicists and astronomers.
Professor Stephen Hawking, who has in the past said that there is certainly alien life out there but has warned humanity against trying to contact them, was among those to back the project.
He said: ‘We believe that life arose spontaneously on Earth. So in an infinite Universe, there must be other occurrences of life.
‘Somewhere in the cosmos, perhaps, intelligent life may be watching these lights of ours, aware of what they mean.
‘Or do our lights wander a lifeless cosmos – unseen beacons, announcing that here, on one rock, the Universe discovered its existence.
‘Either way, there is no bigger question. It’s time to commit to finding the answer — to search for life beyond Earth. The Breakthrough Initiatives are making that commitment.
‘We are alive. We are intelligent. We must know.’
The new projects were launched at a special event at the Royal Society in London.
The 10-year Listen initiative will use the 100 metre (328 feet) Robert C Byrd Green Bank Telescope in West Virginia and the 64 metre (210 feet) Parkes Telescope in New South Wales, Australia, to search for radio signals.
It will also conduct the world’s most extensive search for optical laser transmissions from outer space using the Automated Planet Finder Telescope at Lick Observatory in California, USA.
Professor Lord Martin Rees, Astronomer Royal and a cosmologist at the University of Cambridge, is among those heading up the project.
He will join Dr Frank Drake, the astrophysicist who was one of the founders of the Seti Institute, which searches for extraterrestrial life.
Dr Drake said the Breakthrough Listen program promised to be 50 times more sensitive than previous attempts to listen for life amoung the stars and will cover 10 times more of the sky.
Dr Drake said: ‘Right now there could be messages from the stars flying right through the room, through us all. That still sends a shiver down my spine.
‘The search for intelligent life is a great adventure. And Breakthrough Listen is giving it a huge lift.’
‘We’ve learned a lot in the last fifty years about how to look for signals from space. With the Breakthrough Initiatives, the learning curve is likely to bend upward significantly.’
Experts say that if a civilisation was broadcasting signals with the power of common aircraft radar from one of the 1,000 nearest stars to Earth, the telescopes used in the project could detect them.
The closest star to Earth – Proxima Centauri – is 24 trillion miles away and it takes light from it 4.2 years to reach our planet.
Breakthough Listen’s optical search could also detect a 100 watt laser from some of the nearest stars.
Lord Rees said: ‘The search for extra-terrestrial life is the most exciting quest in 21st-century science.
‘The Breakthrough Initiatives aim to put it on the same level as the other ultimate scientific questions.’
Announcing the initiative, Yuri Milner said: ‘With Breakthrough Listen, we’re committed to bringing the Silicon Valley approach to the search for intelligent life in the Universe.
‘Our approach to data will be open and taking advantage of the problem-solving power of social networks.’
The Breakthrough Message initiative will also offer prizes totalling $1 million for digital messages designed to convey information about our planet to alien life forms.
Ann Druyan, the producer of the science fiction film Contact and a science writer who helped draw up the interplanetary message carried on the Voyager Spacecraft, said: ‘The Breakthrough Message competition is designed to spark the imaginations of millions, and to generate conversation about who we really are in the universe and what it is that we wish to share about the nature of being alive on Earth.
‘Even if we don’t send a single message, the act of conceptualizing one can be transformative.
‘In creating the Voyager Interstellar Message, we strived to attain a cosmic perspective on our planet, our species and our time.
‘It was intended for two distinct kinds of recipients – the putative extraterrestrials of distant worlds in the remote future and our human contemporaries.
‘As we approach the Message’s fortieth anniversary, I am deeply grateful for the chance to collaborate on the Breakthrough Message, for what we might discover together and in the hope that it might inform our outlook and even our conduct on this world.’