Star

A star is a huge ball of hot gas that shines because, deep in its core, it squeezes hydrogen into helium and gives off energy. Its color shows how hot it is: red stars are the coolest and blue stars the hottest. The Sun is a yellow star, about halfway through its life.

Tap it to run the life of a star like the Sun, sped up. It swells into a red giant, puffs off its outer layers as a glowing shell and shrinks to a tiny white dwarf; then a new star lights up. A real star like the Sun takes about 10 billion years to do this. Pick the kind of star in the Splash tab; a tap always plays the Sun's story.