⭐Star Life Cycle: From Nebula to Black Hole

Why it works

Stars are born when a cloud of gas collapses under gravity and its core gets hot enough for hydrogen to fuse into helium. That steady phase, the main sequence, is where a star spends most of its life. A star like the Sun stays there for about 10 billion years; a star 15 times heavier has more fuel but burns it so furiously that it lasts only about 11 million years, shining blue-white at over 20,000 K.

When the core’s hydrogen runs out, the star swells into a red giant. A lighter star then puffs off its outer layers as a planetary nebula and leaves a white dwarf the size of Earth. A star above about 8 solar masses explodes as a supernova, scattering the elements that later make planets and people, and leaves a neutron star or, above about 25 solar masses, a black hole. The slider ages your star through every stage.