A Little Bit Goes a Long Way

The problem with geniuses—or maybe it’s their strength—is that they’re always restless. They just never sit still.

Witness a little project called “Breakthrough Starshot,” announced today at the One World Observatory in New York City. It’s a collaborative venture between Hawking and Yuri Milner, a Russian billionaire known for underwriting some rather ambitious space-related projects.

Just last year, Milner introduced a $100 million project to search for the ephemeral signals of extraterrestrial intelligence. But that’s so last year. Now, Milner aims to seek out ET…by traveling to them.

Breakthrough Starshot plans to take an incremental approach to the monumental difficulties of achieving interstellar exploration. It’s a $100 million investigative program, aiming to suss out the scientific and engineering architecture needed to make an interstellar probe a reality.

We’re not talking hyperdrives and the Starship Enterprise—the idea is much more modest, and more within the realm of possibility. It involves designing and building “nanocraft,” tiny spacecraft attached to lightsails which use the power from gigawatt-scale laser arrays to reach speeds upwards of 20% the speed of light.

That means they could reach Alpha Centauri, 4 light-years away, in only twenty years.

Starchips and Lightsails

“The Breakthrough concept is based on technology either already available or likely to be available in the near future,” Milner explains.

In support of this, prototypes of the new technology were demonstrated at the announcement. The idea is centered on the “Starchip,” a tiny tech wafer weighing a gram or so—essentially a miniature sensors and electronics payload. It contains everything: Cameras, communications package, navigational and autonomous AI computer programs, power supply, and so on. It’s tethered to a “Lightsail,” a meter-sized sheet just a few atoms thick and weighing a few grams at most; this is the nanocraft’s propulsion system.

The idea is that a “phased array” of lasers, packing a combined punch of 100 gigawatts, will push the nanocraft along at speeds up to 161 million kilometers (100 million miles) an hour. A “swarm” of nanocraft can be dispatched to nearby stars, increasing the likelihood that at least one of them will survive the trip.

Moreover, the technology has applications for Solar System exploration as well. Such cheap, lightweight craft could easily zip about the planets; we could eschew bulky, slow, expensive probes for faster, more efficient swarms of nanocraft with comparable instrument packages.

There are, of course, a number of imposing technical obstacles—for example, building powerful enough lasers and devising a means of communicating across the vast distance of interstellar space. But Breakthrough Starshot hopes to solicit advice from the scientific community as well as the general public.

“For the first time in human history we can do more than just gaze at the stars,” Yuri Milner observed. “We can actually reach them.”