Stephen Hawking and Yuri Milner launch $100m star voyage

Tim Radford in The Guardian:

In an unprecedented boost for interstellar travel, the Silicon Valley philanthropist Yuri Milner and the world’s most famous cosmologist Stephen Hawking have announced $100m (£70m) for research into a 20-year voyage to the nearest stars, at one fifth of the speed of light.

Breakthrough Starshot – the third Breakthrough initiative in the past four years – will test the knowhow and technologies necessary to send a featherweight robot spacecraft to the Alpha Centauri star system, at a distance of 4.37 light years: that is, 40,000,000,000,000 kilometres or 25 trillion miles.

A 100 billion-watt laser-powered light beam would accelerate a “nanocraft” – something weighing little more than a sheet of paper and driven by a sail not much bigger than a child’s kite, fashioned from fabric only a few hundred atoms in thickness – to the three nearest stars at 60,000km a second.

More here.