Breakthrough Starshot, the brainchild of everyone's favourite physicist Stephen Hawking and Russian billionaire Yuri Milner, has the goal of getting humanity to the nearest star system, Alpha Centauri, which is 4.37 light years away. Hawking and Milner have proposed doing this with an array of tiny "nanocrafts," and now, the mission has successfully launched the world's smallest spacecraft into orbit around Earth.

The crafts, named "Sprites," are 3.5-by-3.5 centimetre chips, built on a single circuit board—each one is just shy of the size of an Oreo, yet contains computers, sensors, solar panels, and radios. Piggybacking on a couple of German satellites, six Sprites reached low Earth orbit, about 600 kilometres high, on June 23. Two Sprites are currently attached to satellites, and four are in a deployer attached to one of the satellites to be released later.

Zac Manchester, consultant for Breakthrough Starshot who created the concept of the Sprites and Kickstarted them in 2011, raising over $74,000, told Motherboard that this is the first time his team has been able to make a real demonstration of the crafts in space and communicate with them from the ground.

The Sprites, which weigh about four grams each and cost only $25 to make, have basic sensors like magnetometers and gyroscopes, but Manchester hopes to upgrade them with actuators for mobility, as well as more advanced sensors like chemical detectors that would allow them to explore alien environments.

Manchester said that their low cost would allow astronauts to take more risks and send them places they wouldn't usually go: You can picture astronauts in orbit around an alien (and possibly hostile) planet, sending a fleet of Sprites down to take some readings.

"If you want to get up-close and even sample things, you wouldn't want to do that with your billion-dollar satellite," Manchester said. "But you can imagine deploying a whole bunch of these little Sprite spacecrafts and sample directly." Because they're cheap and unmanned, he added, "you wouldn't care if a whole bunch of them were destroyed in the process."

Manchester said that, in the future, several Sprites could be networked together and function as a swarm; each with its own sensors, performing different tasks and sharing information. Since it would take the Space Shuttle some 165,000 years to get to Alpha Centauri with humans inside, sending a fleet of tiny nanobots sounds like a pretty good idea.