Professor Stephen Hawking has backed two new 'breakthrough' initiatives that will focus on searching for alien life.
Joined by Russian entrepreneur Yuri Milner and other key figures in science including astronomer royal Lord Martin Rees, the schemes were announced today at The Royal Society.
Yuri Milner addressing launch attendees:
Those behind the initiative say this is by far the biggest search for intelligent life yet to be carried out, with a $100 million (£64 million) in investment.
The first programme, Breakthrough Listen, is a 10-year commitment that will use two of the world's largest telescopes to scan 10 times more of the sky than previous searches have.
Both telescopes -- the 100 Meter Robert C. Byrd Green Bank Telescope in West Virginia, USA and 64-metre diameter Parkes Telescope in New South Wales, Australia -- will listen for message from the 100 closest galaxies.
This will include a survey of a million stars closest to Earth while also maintaining a look-out for laser transmissions.
However, the hunt will not be left to just the experts. Nine million volunteers around the world will also donate their spare time to find out if planet Earth has company.
Prof Hawking said at the launch:
"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.
"We are alive. We are intelligent. We must know."
The second initiative, Breakthrough Message, is an "international competition to create digital messages that represent humanity and planet Earth."
Milner, who founded both schemes, 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.”