Dwarf Stars

A star of relatively low luminosity and small size is called a dwarf star. Not the most precise term of all, most main sequence stars are dwarf stars. They come in all types of colors:

White Dwarf

A white dwarf is a dwarf star that has exhausted all of its nuclear fuel and has no internal energy production. It is very dense, and is supported by electron degeneracy pressure. It is the final evolutionary stage of a star with a mass of up to 9 solar masses.

Red Dwarf

The coolest and smallest kind of main sequence stars, a red dwarf is a dwarf star is the most common type of star in the universe. They are also the longest-lived stars, with lifespans of up to 10 trillion years. However, as a result of their low luminosity, individual red dwarfs cannot be easily observed, atleast not with the naked eye.

Proxima Centauri, the nearest star to the Sun, is a red dwarf, as are 50 of the 60 nearest stars.

Brown Dwarf

A brown dwarf is a dwarf star that is too small to sustain hydrogen fusion, but still massive enough to fuse deuterium. They are substellar objects, and can barely be called “stars”. They are very dim, making them hard to detect using telescopes, hence they are primarily detected by thir gravitational influence on other objects.

To be considered a brown dwarf, an object must have a mass between 13 and 80 times that of Jupiter. Hence, you may have heard that Jupiter would become a star if it was just 13 times more massive.

Yellow Dwarf

A yellow dwarf is a dwarf star that is similar to the Sun. It is a main sequence star with a mass between 0.9 and 1.1 solar masses. The Sun is a yellow dwarf. The term is actually a misnomer as these type of stars can actually range in color from white to slightly yellow.

Black Dwarf

A black dwarf is a dwarf star that has cooled down to the point where it no longer emits any light. They are the final evolutionary stage of a star with a mass of less than 0.8 solar masses. However, since the universe is only 13.8 billion years old, no black dwarfs have formed yet.

More colorful dwarf stars such as blue dwarfs and orange dwarfs exist, but are not covered in this wiki. You may read more about them on the internet.