A long way FROM HOME
Planetary flybys have provided fascinating insights into the Solar System's members. Now we need to encounter the exoplanets.
By far the best way to study an exoplanet would be to send a spacecraft to go and take a look at one. The Breakthrough Starshot project, funded by Russian billionaire Yuri Milner and supported by British cosmologist Stephen Hawking, is planning to do just that. But it’s going to be tough (not to mention expensive) and it won’t happen any time soon.
The nearest known exoplanet, Proxima Centauri b, is 4.2 lightyears away, some 40 billion kilometres. Even at 20 per cent of the speed of light (c), it will take over 20 years to get there. By comparison, Voyager 1, the fastest spacecraft humans have ever launched into space, only travels at 0.007 per cent of light speed.
Breakthrough Starshot’s plan is to launch a swarm of tiny lightweight satellites into space. Each satellite will have ultra-thin light sails. A huge array of extremely powerful lasers on Earth will fire beams at the sails to accelerate the craft to 0.2c within minutes. The stamp-sized ‘nano-craft’ will carry cameras and spectrographs to collect data during the trip through the Proxima system.
Images and data would then take another 4.2 years to reach Earth. So if Breakthrough Starshot were to launch in 2030, which is extremely optimistic, our first exoplanet close-ups won’t reach us until 2055 at the earliest. Until then, we’ll have to make do with artistic impressions of any potential twins of our home planet.