Mission requires a huge laser and an unbreakable starship

A fleet of spacecraft weighing only a few grams each could travel to the closest star at a speed of 216 million km/h. The scientists behind the Breakthrough Starshot project hope to launch the first light-powered craft 20 years from now.

1 MOTHERSHIP ENTERS ORBIT

A mothership carrying 1,000 tiny spacecraft is entered into orbit

60,000 km above Earth. Once a day, a tiny craft consisting of a microchip and a 16 m2 light sail is released. The craft is placed above the laser.

2 MILLIONS OF LASERS UNITED INTO ONE

A beam of 100 gigawatts consists of millions of small, 10 kilowatt lasers that are united into one beam. It is a huge challenge to unite millions of beams. In 10 minutes, the laser will accelerate the light sail to one fifth of the speed of light.

3 PROJECT REQUIRES EXTREME ACCURACY

To hit the sail millions of km from Earth, the laser gun must have an accuracy of much less than one millionth of a degree. The laser must be fired when Earth is located in a specific position in relation to Alpha Centauri, and no planets or asteroids are in the way.

4 STURDY, ULTRALIGHT LIGHT SAIL

Both the light sail of 4x4m and the ”skeleton” holding it in place must be very sturdy. The skeleton could be made of composites such as carbon fibre, whereas the sail could be made of silicon, graphene, or plastic film coated with aluminium.

5 THE TECHNOLOGY IS ALMOST READY

The tiny ChipSats must bring several scientific instruments, but the total weight cannot exceed a few grams. Satellites

like this already exist, so in this respect, the project is very close to possible right now.