“It isn’t only the beauty of the night sky that thrills me. It’s the sense I have that some of those points of light are the home stars of beings not so different from us, daily cares and all. who look across space with wonder, just as we do.” -Frank Drake
What is it that makes our Solar System special? It’s Earth, of course. A rocky planet of the right mass and composition, the right distance from our Sun, the right atmosphere, the surface oceans, and all the life that’s ensued is what makes us special. Not just special, but unique, at least among the planets we’ve found so far.
But there are other planetary systems out there with Earth-like worlds. Similar to Earth in mass, size, temperature and many other conditions, these might represent planets where life similar to what we find here arose. For the first time, we’ve found a planetary system with not just one Earth-like, potentially habitable world, but three!