He is part of a group of scientists that believe they can send "nano-crafts" within a generation
Cosmologist Stephen Hawking is joining a group of scientists and philanthropists to announce their ambition to reach a distant star system within a generation.
The group, led by investor and physicist Yuri Milner, believes that rapid advances in nano and laser technologies mean it will be possible to capture images of planets and gather other scientific data from Alpha Centauri.
The Alpha Centauri star system is 25 trillion miles, or 4.37 light years, away.
Using today’s fastest spacecraft, it would take about 30,000 years to get there.
But Yuri Milner’s group believes this journey may eventually be possible using nano-spacecraft propelled by lasers.
They also claim the nano-spacecraft could reach Alpha Centauri just over 20 years after launch.
The scientists believe it will be possible to produce nano-spacecraft about the size of a small coin or stamp that will carry cameras, a power supply, navigation and communication equipment and a space probe.
They say that the rising power and falling cost of lasers means they could be made powerful and accurate enough to propel the nano-spacecraft further than man-made hardware has ever gone before.
So far, no nano-spacecraft has been successfully sent further than the earth's orbit.
Philanthropist Mr Milner is devoting $100m (€88m) to the first phase of this ambitious project, which he is calling Breakthrough Starshot.
He intends to run a research grant and funding scheme to encourage groups of scientists and other experts to figure out ways to overcome the many challenges currently in the way of success.
But the funding required to actually build and operate such a massive project would eventually run into billions.
Spokespeople for the initiative have told Sky News that the aim is to build an organisation that compares to NASA in its scope, scale and impact.
As well as Mr Hawking, the project has attracted the attention of Facebook CEO Mark Zuckerberg, who is also on the board that will oversee progress.
In an interview with Sky News, Mr Milner said: "The exciting thing is that we don't need to discover new laws of nature or develop brand new technologies to make this happen. The challenge is to scale and develop the existing technologies, and that will take time. The human story is one of great leaps. Fifty-five years ago today, Yuri Gagarin became the first human in space. Today, we are preparing for the next great leap - to the stars."
In a statement Mr Hawking said: "Earth is a wonderful place, but it might not last forever. Sooner or later, we must look to the stars. Breakthrough Starshot is a very exciting first step on that journey."