Ask Astro: What will white dwarfs, neutron stars, and brown dwarfs look like at the ends of their lives?

What will white dwarfs, neutron stars, and brown dwarfs look like at the very end of their lives, when they no longer emit radiation?

Bill Zuna

Tallahassee, Florida

Let’s look at a white dwarf first. These stellar remnants are the remains of Sun-like stars and are made mostly of carbon and oxygen. A white dwarf’s outer shell is so hot that it will radiate visible light for about 1010 — that’s 1 followed by 10 zeros — years. By then, the atoms will have cooled