Red stars are a type of star that emit a reddish hue due to their relatively low surface temperatures, typically below 3,500 degrees Celsius. These stars are often classified as M-type stars in the Hertzsprung-Russell diagram, which is a tool used by astronomers to categorize stars based on their brightness and temperature. One of the most well-known red stars is Betelgeuse, located in the constellation Orion. Red stars are generally larger than our sun and can be found in various stages of their life cycle, often representing the later stages of stellar evolution as they expand and cool.