These planets weren’t supposed to be found—but once discovered, there was only one thing to do. Each one reacts differently, and the results get more intense every time. What starts as curiosity ...

How far it is from the sun: 886 million miles (1.4 billion kilometers), on average How big it is: 72,400 miles (116,500 km) across, or almost 10 times the size of Earth. How many moons it has: At ...