Alpha Gem: 49: 1.57: 0.5: A1V + A2V: Gacrux: Gamma Cru: 120: 1.63 (var.)-1.2: M3.5III: Shaula: Lambda Sco: 330: 1.63 (var.)-3.5: B1.5IV: Magnitudes The magnitude scale was invented by an ancient Greek astronomer named Hipparchus in about 150 B.C. He ranked the stars he could see in terms of their brightness, with 1 representing the brightest …
http://www.astro.wisc.edu/~dolan/constellations/extra/brightest.html

