dværgstjerne

A dværgstjerne, or dwarf star, is a star that is in the main sequence phase of its stellar evolution. This is the longest and most stable period in a star's life, during which it fuses hydrogen into helium in its core. The term "dwarf star" is often used in contrast to giant stars, which are significantly larger and more luminous. Our own Sun is an example of a dwarf star, specifically a G-type main-sequence star.

Dværgstjerner vary greatly in size, mass, and temperature, which determines their color and luminosity. Smaller, cooler dwarf stars are red and have lower luminosity, while larger, hotter dwarf stars are blue or white and are much more luminous. The mass of a dwarf star is the primary factor in its lifespan. More massive dwarf stars burn through their nuclear fuel much faster and have shorter lifespans compared to less massive ones.

The classification of dwarf stars is part of the Morgan-Keenan (MK) spectral classification system, which categorizes stars based on their temperature and spectral characteristics. The main sequence is denoted by the spectral type 'V'. Therefore, a dwarf star is technically a main-sequence star of luminosity class V. When a star exhausts the hydrogen in its core, it leaves the main sequence and evolves into a different type of star, such as a red giant or a white dwarf, depending on its initial mass.