Kääpiötähden

Kääpiötähden is a Finnish term that translates to "dwarf star" in English. In astronomy, a dwarf star is a star of very low luminosity and radius. The term is often used to refer to stars that are smaller and cooler than the Sun, and that are in the process of burning their nuclear fuel. This category includes red dwarfs, white dwarfs, and brown dwarfs. Red dwarfs are the most common type of star in the Milky Way galaxy. They are small, cool, and have a long lifespan, burning their hydrogen fuel very slowly. White dwarfs are the remnants of stars that have exhausted their nuclear fuel and have shed their outer layers. They are very dense and hot but slowly cool down over billions of years. Brown dwarfs are objects that are more massive than planets but not massive enough to sustain nuclear fusion in their core. They are sometimes called "failed stars." The study of dwarf stars is important for understanding stellar evolution, the formation of planetary systems, and the overall composition of galaxies. Their low luminosity makes them challenging to observe, but advancements in telescope technology have greatly improved our ability to detect and study them.