White Dwarf Stars

White dwarf stars are like cosmic diamonds - they're incredibly small, super hot, and amazingly dense! These stars are what's left behind when red giant stars finish their lives and shed their outer layers into space. What remains is the hot, dense core, which becomes a white dwarf. Even though white dwarfs are about the size of Earth, they contain almost as much mass as our entire Sun! This makes them so dense that just a teaspoon of white dwarf material would weigh as much as a car.

White dwarfs start out incredibly hot - over 100,000°F on their surface - which is why they glow brilliant white. But since they're no longer making energy in their cores, they slowly cool down over billions of years. Eventually, they'll become cold, dark objects called "black dwarfs," but this takes so long that no black dwarfs exist yet in our universe!

Five Famous White Dwarfs:

Sirius B - The companion to Sirius, the brightest star in our sky. This white dwarf orbits around Sirius A every 50 years and is nicknamed "the Pup."

Procyon B - The white dwarf companion to Procyon, located 11 light-years away. It's very difficult to see because bright Procyon A outshines it.

40 Eridani B - One of the closest white dwarfs to Earth at 16 light-years away, orbiting in a triple star system with two other stars.

Van Maanen's Star - A nearby white dwarf only 14 light-years away, named after the Dutch astronomer who discovered it in 1917.

Wolf 1346 - An old, cool white dwarf that's been cooling for over 12 billion years, making it one of the oldest stars we know.