Stars are grouped according to their spectral characteristics by single letters of the alphabet, optionally with numeric subdivisions.

The seven main types of stars. How they’re classified and their roles in stellar evolution, lifecycle stages, and how they appear in the night sky.

This diagram shows typical average properties for the different types of stars. There is also a negative version of this diagram which might be easier to print.

Dec 4, 2025 · The generally accepted system of stellar classification is a combination of two classification schemes: the Harvard system, which is based on the star’s surface temperature, …

Star classification chart & guide. Learn about all the main star types and their characteristics, including life cycle, mass, size, luminosity, temperature.

This chart displays the different classifications of stars, their average temperature, and their average size. After measuring the properties of individual stars, how do astronomers use this …

O stars are the least common and M are the most common found in the main sequence of stars. Stars near the beginning or end of their lives are not part of this classification. The new system …

Dec 18, 2025 · Scientists call a star that is fusing hydrogen to helium in its core a main sequence star. Main sequence stars make up around 90% of the universe’s stellar population. They …

There are seven main types of stars. In order of decreasing temperature, O, B, A, F, G, K, and M. O and B stars are uncommon but very bright; M stars are common but dim.. An easy …

In astronomy, stars are classified based on their spectra. Different types of stars (listed below) have different spectral characteristics and, even though they only differ in brightness to the …