StarChips, Not Starships, Proposed for Trips to Alpha Centauri

Russian billionaire Yuri Milner, renowned physicists Stephen Hawking and Freeman Dyson, and former NASA Ames Center Director Pete Worden were among the members of a high profile group that announced a “Breakthrough Starshot” initiative today, the 55th anniversary of Yuri Gagarin’s historic flight into space.  Milner, who was named after Gagarin, is devoting $100 million of his fortune for phase one of the effort to send hundreds or thousands of postage stamp sized spacecraft to Alpha Centauri, the closest star, 4.37 light years away.

Speaking at the One World Observatory in New York City, Milner described advances in microfabrication, nanotechnology and photonics that have or will make it possible to send tiny spacecraft (nanocraft) on such a journey using laser-propelled sails (lightsails) for propulsion.  Experiments with solar sails have already taken place, but the energy of our Sun is insufficient to send a spacecraft to such a distance.  Instead, an array of lasers on Earth will provide the force to push the “StarChips” along at a very high velocity — 20 percent of the speed of light.

A spacecraft could reach Pluto in three days at that velocity, compared to the 9.5 years required for the New Horizons mission using chemical propulsion.   For the StarChips, the journey to Alpha Centauri would take 20 years instead of 30,000 years.    

Milner envisions launches of the spacecraft, perhaps one a day, will begin in 15-20 years, though he stressed that the time frames are notional. The idea is that by launching hundreds or thousands of the StarChips, the overall mission of sending spacecraft to fly past planets orbiting another star can be achieved even if many lose their way or are damaged by collisions with interstellar dust, for example.

Freeman Dyson, who has done pioneering theoretical work in interstellar travel, participated in the panel to offer a “dissenting” view that there will be many interesting objects along the way and the focus should not be just on getting to Alpha Centauri.  He believes that life is most likely to be found not on planets, but small bodies like comets and asteroids.  The space between here and Alpha Centauri is not a void, he said, but filled with “trillions” of asteroids and comets that will underpin a sustainable program of exploration rather than focusing on just a single destination.

The project is one of a series sponsored by Breakthrough Initiatives, which describes itself as a program of scientific and technological exploration probing the big questions of life in the universe.

Milner, Hawking and Facebook CEO Mark Zuckerman form the Board of the Starshot program.  Milner described it as a research and engineering program to demonstrate proof of concept, to be followed by a demonstration phase and then the actual launches.  Worden will lead the program.

Worden said he has spoken with NASA leaders and they are “eager” to support the idea.  He pointed out that much of the work on nanocraft and lightsails that Milner described was funded through the NASA Innovative Advanced Concepts (NIAC) program.

The $100 million will fund research grants and support relevant scientific and engineering research and development.   All the research will be in the public domain and the activity is envisioned as a global effort.