The phrase "brightest star" refers to the star that appears to shine the most brightly in the sky. It is often used to describe someone or something that stands out and is exceptional in a certain area or field. Full definition
To the naked eye, they blend together to appear as the third brightest star in the night sky. (newscientist.com)
A barred spiral galaxy is a spiral galaxy with a band of bright stars emerging from the center and running across the middle of the galaxy. (sciencedaily.com)
See pop classical music's brightest star on the big screen! (digitalchumps.com)