What is the Sun to a star ratio of luminosity from the reference point of Earth?
“Luminosity” is a term used to define the total energy outflow (power) from a star. This number is not dependent on distance from Earth – it’s an absolute number. Luminosity Stars range in luminosity from utter black (no luminosity) to extraordinarily brilliant (massive blue-white stars) to unbelievable (quasars, if quasars are even stars, that is!). So any ratio is dependent on the star you pick to compare our Sun to. Our sun is a smallish star – a “dwarf” – burning hydrogen in the main phase of its life, called the “main sequence,” and is classified as a G2 V star. According to my book (Astrophysical Quantities), it puts out energy on the order of 3.828x10e26 (that’s 10 raised to the power of 26) watts – quite a light bulb!. The brightest star, not including the Sun, is Sirius (in the constellation Canis Major). I picked Sirius to compare to because 1) it’s bright as seen from Earth, and 2) it is a lot like our Sun, only more massive (approximately 6.3 times bigger than our Sun). The
