White Dwarfs

A white dwarf is what is left when a normal star dies. It is very small, about the size of Earth. But it is still very hot. White dwarfs shine with a bright white light. They slowly cool down over billions of years.

How They Are Made

Stars like our Sun turn into red giants when they get old. Then they blow off their outer layers. The hot center that is left is the white dwarf. It does not burn fuel anymore, but it still glows.

A size chart comparing a white dwarf star with the Sun.
A size chart comparing a white dwarf star with the Sun. (RJHall / Wikimedia Commons)

Heavy and Small

White dwarfs are tiny but very heavy. One spoonful would weigh as much as a car. They have strong gravity. Over a very long time, a white dwarf will cool and fade away.

Fun Facts

  • Our Sun will become a white dwarf one day.
  • White dwarfs can stay hot for billions of years.
  • Some are made mostly of carbon, like giant diamonds.

Did You Know?

Scientists have found a white dwarf that may have a core made of crystal!