The newly discovered planet Proxima b is about to change the focus of astronomy for decades to come -- and maybe longer, if it reveals signs of life. The planet, some 25 trillion miles away from our own, is like a twin to Earth, but one separated at birth and living a very different kind of life.
The discovery, which was announced in the journal Nature, represents by far the closest habitable planet to Earth -- near enough that humans could take pictures of it, if not with today's telescopes, then with ones that will come online soon. If the planet is like Earth, these near-future telescopes could pick up hints of vegetation and sunlight glinting off the ocean.
And Proxima b looks a lot like Earth. It's only a little bigger than our planet, according to scientists' calculations, and it sustains about the same average temperature. The star it orbits, Proxima Centauri, is the sun's closest neighbor. Significantly, astronomers believe the planet, like ours, is in the "habitable zone" of its star, which means liquid water could exist on its surface. And liquid water could mean life.