If you happen to be enjoying a sunny day, thank the bright surface of the sun, known as the photosphere. At a piping hot ...

He wasn't wrong—the sun is 99.8 percent of the mass of the solar system. But what is that giant ball of fire in the sky? How ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. A partial solar ...