Sailing to Alpha Centauri at 100 million mph

Astronomers estimate that there is a reasonable chance of an Earth-like planet existing in the ‘habitable zones’ of Alpha Centauri’s three-star system. A number of scientific instruments, both ground- and space-based, are being developed and enhanced, which will soon identify and characterise planets around nearby stars.

Breakthrough Starshot is a $100m research and engineering programme aiming to demonstrate proof of concept for light-propelled nanocrafts. These could fly at 20% of light speed, or approximately 671 million mph, and capture images of possible planets and other scientific data in our nearest star system, Alpha Centauri, just over 20 years after their launch.

Stephen Hawking commented: "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.”

The programme will be led by Pete Worden, Former Director AMES Research Center, NASA, and advised by a committee of world-class scientists and engineers. The board will consist of Stephen Hawking, Yuri Milner and Mark Zuckerberg.

Breakthrough Starshot aims to establish whether a gram-scale nanocraft, on a sail pushed by a light beam, can fly over a thousand times faster than today's current spacecraft. It brings the Silicon Valley approach to space travel, capitalising on exponential advances in certain areas of technology since the beginning of the 21^st century.

Nanocrafts are gram-scale robotic spacecrafts comprising two main parts: the StarChip and the Lightsail. The starchip will be a gram-scale wafer, carrying cameras, photon thrusters, power supply, navigation and communication equipment, constituting a fully functional space probe. This will be combined with metre-scale sails no more than a few hundred atoms thick and at gram-scale mass. The nanocraft would be propelled by a light beamer, huge phased arrays of lasers which could potentially be scaled up to the 100 gigawatt level).

Breakthrough Starshot aims to bring economies of scale to the astronomical scale. The StarChip can be mass-produced at the cost of an iPhone and be sent on missions in large numbers to provide redundancy and coverage. The light beamer is modular and scalable. Once it is assembled and the technology matures, the cost of each launch is expected to fall to a few hundred thousand dollars.