On Friday evening, a mysterious burst of light tore through the southern California sky. The spectacle was SpaceX's final performance of 2017, an encore launch of a recycled rocket. Drivers pulled over as onlookers gaped and shared dumbfounding footage on social media feeds. Yet this launch was but a comma really in an age of inspiring feats of space exploration. This past year, the banter of billionaires has dared us to dream of orbital tours at the edge of space, futuristic communities on Mars, and even an entirely space-based nation. Around the globe, world leaders are urging citizens and scientists to think outside Earth's orbit. In October, the United Arab Emirates announced plans to build a simulated Martian city in the Arabian Desert. This summer, the tiny nation of Luxembourg took steps to establish a legal framework around mining asteroids. And in the United States, President Trump this month directed NASA to resume crewed flights to the moon as a step toward human spaceflight to Mars and beyond. The space race, it seems, is back on. But this time around, there's more than one main event. – Noelle Swan