BURNING QUESTIONS FOR PROXIMA B

Can I go?

Sorry. Our next planetary target for human exploration is Mars, which will be hard enough to achieve by 2040 as NASA hopes. To name one challenge, we haven’t figured out how to shield astronauts from the radiation they would absorb on the minimum yearlong journey to Mars.

Can robots go?

The Starshot initiative will spend $100 million (U.S.) over the coming years to demonstrate proof-of-concept for a truly ambitious plan: to build a massive array of lasers that would beam thousands of lightsail-equipped miniature “nano-crafts” towards Alpha Centauri at 20 per cent the speed of light, a journey that would take 20 years. One hurdle — whether any interesting exoplanets exist there — was resolved on Wednesday. But engineering challenges remain, and other scientists believe it will take centuries for such a journey to become feasible.

Fine, what can we do now?

Our current class of ground-based telescopes is already sensitive enough to start studying Proxima b’s atmosphere, if it has one — especially if it transits the face of Proxima Centauri, though the Pale Red Dot team did not observe that occurring and believe there’s only a small chance it will. A new generation of mega-telescopes is under construction and as they come online in the next decade, astronomers will have even more powerful instruments to detect light from the planet directly. The closeness of Proxima b boosts their chances of success.

What about next year?

NASA’s Transiting Exoplanet Survey Satellite, set to launch in 2017, will spend two years in space monitoring 500,000 nearby stars, searching for drops in brightness that indicate the transit of exoplanets. The scientists building TESS expect to catalogue about 500 planets transiting very bright nearby stars. There’s only a small chance TESS will provide data on Proxima b, but an excellent chance that TESS will find other prime planetary candidates for observation. Kate Allen