The competition heats up: A Russian billionaire has announced a $100 million investment in an effort to use lasers to propel cellphone-sized spacecraft on an interstellar voyage to Alpha Centauri.
Called Breakthrough Starshot, the programme is based on an idea that has been around for decades: the solar sail. The theory is that a lightweight space sail could harness the momentum carried by photons in order to travel without fuel.
The Breakthrough Starshot team is betting that a burst of concentrated lasers, fired from the ground, could rapidly accelerate a mobile-phone-sized device equipped with microelectronics and a tiny sail — providing much more energy than could be harnessed from the Sun. Whereas NASA’s plutonium-powered New Horizons spacecraft took nine years to reach Pluto, the “nanocraft” envisioned by Breakthrough Starshot would pass by the dwarf planet and exit the Solar System in three days.
The project’s initial US$100-million budget covers only research and development of such a spacecraft. But Breakthrough Starshot’s ultimate goal is to demonstrate proof of concept for an international programme that would send a fleet of nanocraft into space. Doing so would require the group to surmount enormous scientific and engineering challenges in developing the necessary laser technology, materials and communications systems.
This technology is related though not identical to an earlier story about using lasers to power spacecraft.