Breakthrough Starshot Aims to Send Interstellar Probes to Alpha Centauri

Stephen Hawking, Yuri Milner and Mark Zuckerberg want to propel nanocrafts with gigawatt lasers.

The Breakthrough Starshot concept.

Breakthrough Starshot is a USD$100 million research and engineering program with the goal of demonstrating a proof of concept for light-propelled gram-scale space probes called nanocrafts.

The Alpha Centauri star system is 4.37 light years (25 trillion miles) away, which means that the fastest spacecraft today would take approximately 30,000 years to get there.

However, the nanocrafts could fly more than a thousand times faster at up to 20 percent of the speed of light. At that rate, they could reach Alpha Centauri 20 years after their launch.

Nanocrafts and Light Beamer

The proposed spacecraft would consist of two main parts, dubbed ‘StarChip’ and ‘Lightsail.’

The former would pack cameras, photon thrusters, a power supply and navigation and communication equipment into a gram-scale wafer.

The latter refers to meter-length sails no more than a few hundred atoms thick composed of metamaterials produced using nanotechnology.

The other half of the Starshot project, the “light beamer,” involves a phased array of lasers that could potentially be scaled up to the 100 gigawatt level.

The idea is simple: mass produce StarChips at the cost of an iPhone and send them on missions in large numbers to provide redundancy and coverage.

Check out a commentary on the technology from Pete Klupar, Breakthrough Starshot’s director of engineering, in the video below:

Pete Klupar, director of engineering at Breakthrough Starshot.

Engineering Starshot

Not surprisingly, the project’s proof of concept phase alone is expected to last for years. The mission to Alpha Centauri alone would require a budget comparable to the largest scientific projects today.

The Large Hadron Collider, for example, cost USD$4.75 billion to construct and has an annual operating cost of roughly USD$1 billion.

The organization has already identified the engineering challenges that would need to be met in order to launch the Alpha Centauri mission, many of which are major technological hurdles. They include:

  • Building a ground-based kilometer-scale light beamer at high altitude in dry conditions
  • Generating and storing several gigawatt hours of energy per launch
  • Launching a ‘mothership’ carrying thousands of nanocrafts to a high-altitude orbit
  • Focusing the light beam on the lightsail to accelerate individual nanocrafts to the target speed within minutes
  • Accounting for interstellar dust collisions en route to the target
  • Capturing images and other scientific data and transmitting them back to Earth using a compact on-board laser communications system
  • Using the same light beamer that launched the nanocrafts to receive data from them over four years later

The Breakthrough Starshot Initiative

The initiative is laudable for its commitment to transparency. The project is based entirely on research in the public domain and will publish new results as they emerge.

There’s even a public forum for making comments and suggestions.

The initiative will also establish a research grant program to support relevant scientific and engineering research and development.

Stephen Hawking, Mark Zuckerberg and Russian venture capitalist Yuri Milner comprise Breakthrough Starshot’s board of directors. Pete Worden, former director of NASA’s Ames Research Center stands as executive director.

Other notable members of the initiative’s management and advisory committee include:

  • Avi Loeb, theoretical physicist at Harvard
  • Freeman Dyson, theoretical physicist at Princeton
  • Lou Friedman, astronautics engineer
  • Peter Klupar, former director of engineering at NASA’s Ames Research Center

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

For more information, visit the Breakthrough Initiatives website.