Stars don't *directly* turn into white dwarfs. It's a process that occurs in stages:
1. Main Sequence: A star spends most of its life fusing hydrogen into helium in its core. This is the "main sequence" phase.
2. Red Giant: When the hydrogen fuel runs out, the core contracts and heats up. This causes the outer layers of the star to expand and cool, turning it into a red giant.
3. Helium Fusion: In some stars, the core gets hot enough to fuse helium into heavier elements like carbon and oxygen.
4. Planetary Nebula: After helium fusion, the outer layers of the star are ejected, creating a beautiful, glowing shell called a planetary nebula.
5. White Dwarf: The remaining core, now incredibly dense and mostly made of carbon and oxygen, becomes a white dwarf.
So, a white dwarf is the final stage of a star's life, but it's not the direct transformation from a star. It's the result of a complex series of events that occur as the star runs out of fuel and sheds its outer layers.
Important Note: Not all stars become white dwarfs. Only stars with masses up to about 8 times the mass of our Sun end their lives as white dwarfs. More massive stars undergo more dramatic final stages, eventually collapsing into neutron stars or black holes.
