How big it is: 865,000 miles (1.392 million kilometers) across How far away it is: 93 million miles (150 million km) What type of star it is: A yellow dwarf star The sun is the star at the center of ...

Isaac Asimov described the solar system as the sun, Jupiter, and debris. 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 ...