What distinguishes Aldebaran in the constellation Taurus?

Aldebaran is distinguished in the constellation Taurus primarily as a red giant star. This classification is significant because red giants are evolved stars that have exhausted the hydrogen in their cores and have expanded and cooled, resulting in their reddish hue. Aldebaran is not just any star—it is the 14th brightest star in the night sky and one of the most prominent stars in Taurus, making it a key feature for locating the constellation.

Being a red giant also means that Aldebaran has a much larger radius and luminosity compared to that of the Sun. This evolutionary stage represents an important phase in stellar life cycles, providing astronomers with insights into stellar development and the lifecycle of stars.

While Aldebaran is indeed one of the brightest stars in the night sky, the essential characteristic that sets it apart in Taurus is its status as a red giant.