Question

Albireo, a star in the constellation of Cygnus, is a binary system whose two components can be seen easily with even a small telescope. Viewers describe the brighter star as "golden" and the fainter one as "sapphire blue." What does this tell you about the relative temperatures of the two stars?

Answer 1

The one that is blue is a hotter star
When studying the temperature of a star, the scientists first look for color. If the color is more reddish, it’s cooler; if it’s yellow/orange, it is a warmer star; and if it’s a blue star, it’s a hot star