cohort. n. 1. (Military) one of the ten units of between 300 and 600 men in an ancient Roman Legion. 2. any band of warriors or associates: the cohorts of Satan. 3.
As an early M-type supergiant, Betelgeuse is one of the largest, most luminous and yet one of the most ethereal stars known. A radius of 5.5 AU is roughly 7003118000000000000â 1180 times the radius of the Sunâable to contain over 2 quadrillion Earths (2.15 Ã 1015) or more than 1.6 billion (1.65 Ã 109) Suns.
Similarly, the color index for red Betelgeuse is. B - V = -2.5 log (Fb/Fv) = -2.5 log (0.18) = 1.85. The color indices, like the magnitude scale, run backward. Hot and blue stars have smaller and negative values of B-V than the cooler and redder stars.