kääpiötähti
Kääpiötähti, or dwarf star in English, refers to a star that is in the main sequence stage of its life cycle. This is the longest and most stable phase for most stars, including our Sun. During the main sequence, stars generate energy by fusing hydrogen into helium in their cores. The size, temperature, and luminosity of a dwarf star depend on its mass, with more massive stars being hotter, larger, and brighter. Kääpiötähti is a broad classification and can encompass various types of stars, from small, cool red dwarfs to large, hot blue dwarfs. Red dwarfs are the most common type of star in the universe and have very long lifespans. Blue dwarfs are much rarer and have shorter, more energetic lives. The term "dwarf" in this context does not imply that the star is small in absolute terms, but rather that it is not a giant or supergiant star, which represent later, more evolved stages of stellar evolution.