A blue dwarf is a type of star that is smaller and cooler than a blue giant but still significantly hotter than most other stars. These stars fall into the category of main-sequence stars, specifically in the spectral class of B to A. Blue dwarfs are characterized by their blue hue, which is a result of their high surface temperatures, ranging from about 10,000 to 30,000 degrees Celsius.
The term ‘blue dwarf’ is often used in contrast to more massive blue giants, and it refers to stars that have diminished in size as they aged. Unlike large stars that are fated to end their lives in spectacular supernovae, blue dwarfs live much longer, burning through their hydrogen at a slower rate.
Although they are relatively common in the universe, blue dwarfs are not as well-studied or observed as other types of stars due to their intrinsic brightness and the fact that they are typically located far away from Earth. Understanding blue dwarfs contributes to our overall knowledge of stellar evolution, especially in understanding how different stars age and interact in various environments in the cosmos.