Blue supergiants are extremely luminous and massive stars, but they are typically too faint to be visible to the naked eye from Earth. Most blue supergiants require telescopes or binoculars to observe due to their distance and brightness. However, there is one notable exception:
Rigel (Beta Orionis): Rigel is the brightest star in the constellation Orion and one of the most luminous stars visible from Earth. It is a blue supergiant and can be seen without the aid of telescopes or binoculars. Rigel is located in the "foot" of Orion, and its bluish-white color makes it quite distinctive. It is a complex and fascinating system, composed of multiple stars.
While Rigel is visible to the naked eye, it's important to note that its visibility depends on factors such as atmospheric conditions, light pollution, and the observer's location. In darker skies with clear conditions, Rigel can be easily spotted as one of the brightest stars in the night sky.