Stephen Hawking's space probes eye the express lane to neighboring stars

Stephen Hawking's space probes...
The Breakthrough Starshot proposal anticipates certain advances in technology before we reach Alpha Centauri
The Breakthrough Starshot proposal anticipates certain advances in technology before we reach Alpha Centauri
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The Breakthrough Starshot proposal anticipates certain advances in technology before we reach Alpha Centauri
The Breakthrough Starshot proposal anticipates certain advances in technology before we reach Alpha Centauri

The Alpha Centauri star system is a fair old hike. At 25 trillion miles (4.37 light years) away, it would take around 30,000 years for us to roll into the area, and that's if we hitched a ride on today's fastest spacecraft. If the latest idea from the cosmically inquisitive Stephen Hawking comes to fruition, however, we could reach this neighboring stellar system within 20 years of launch.

The US$100 million Breakthrough Starshot program, which also has the backing of entrepreneur Yuri Milner and Facebook CEO Mark Zuckerberg, will investigate how small, lightweight spacecraft could be used to cut the travel time between us and our nearest star system. This could see these "nanocraft" zipping along at 20 percent of light speed, or more than 1,000 times faster than the spacecraft we use today.

These nanocraft would be based on gram-scale chips carrying cameras, photon thrusters, power supplies, navigation and communication equipment, offering the same functionality as a conventional space probe. These chips would be combined with LightSails no more than a few hundred atoms thick to pull the nanocraft along at up to 100 million mph, propelled by huge laser arrays.

Astronomers guess that there's a reasonable chance of finding an Earth-like planet sitting in the habitable zones within the Alpha Centauri system. Once the nanocraft arrive, they would gather scientific data and transmit it back to Earth, where it would be received through the same laser array used for launch over four years later.

All of this would require some serious legwork here on the ground, including construction of a kilometer-scale laser array beamer, capacity to store a few gigawatt hours of energy for each launch and the ability to launch a mothership loaded with thousands of nanocraft into high altitude orbit.

Beyond that, the proposal anticipates certain advances in technology, but it is claimed that the main elements of the proposed system are based on those already available, or those "likely to be attainable in the near future." The program will kick off with a research and engineering phase, which is expected to take a number of years.

The Breakthrough Starshot proposal is part of a wider program launched by Hawking and co last year called the Breakthrough Initiatives, aimed at galvanizing the search for extraterrestrial life. Among the other endeavors already launched under the banner is a 10-year mission to scour the closest 1,000,000 stars on the galactic plane for signs of intelligent life and a million dollar competition to inspire ideas for how we could communicate with such life should it be found.

"Earth is a wonderful place, but it might not last forever," says Stephen Hawking, "Sooner or later, we must look to the stars. Breakthrough Starshot is a very exciting first step on that journey."

Source: Breakthrough Initiatives

Roy Murray
Great idea but how will the nanocraft slow down when it arrives?
Actually, won't the lightsails act as brakes of a sort as they approach distant stars and the light from those stars, beaming in the opposite direction, effective stop forward motion?
Douglas Bennett Rogers
There will be a significant drag from interstellar protons. When the impact energy exceeds 4 KEV there will be fusion with any hydrogen in the sail!
@Roy Murray It wouldn't slow down, just pass through the star system seeing what it can see on the way.
But when it has arrived, how are you going to fit useful sensors on something the size of a postage stamp?
If it does manage to find anything, how will it have the equipment and energy required to get a message back to Earth over a distance of more than 4 light years?
Stephen N Russell
Or use the Moon to beam power to nanosats alone from fixed base or in Orbit.
We could do a lot of good on this planet for $100 million or whatever this project finally costs. Investing that much money and human resource on finding extraterrestrial life and exo-planets is tantamount to betting against Earth. It is fact that we already know more about the heavens than our own oceans. This is a case of a few people going beyond what is ethical, acting on some personal aspiration, while potentially putting the rest of the human race in in harms way. Building a land or satellite based laser this powerful could also be used against people or countries, not good. This is a twisted plot, like a self-fulfilling prophecy from some warped sci-fi film. Just because some of these people are intelligent and have a lot of money, doesn't make them smart, or right.
amazed W1
Don't want to be a spoil-sport, but how would the nanocraft cope with an interstellar collision? At millions of mph even a speck of dust might be lethal and "space" is by no means empty space. The engineering may well prove to be the real problem even if the relevant technologies are developed.
Would it be possible to power a Nanocraft on the Vertices of three or more Laser Beams or Streams with another Laser Vertices superimposed at close range to the Nanocraft Propulsion Vertices which clears the way in order to avoid the possible interstellar collision ? Then the Propulsion Vertices could even be used like remote strings to effect a return to earth of the Nanocraft’s information transmission .