Stars

STARS Magnitudes The magnitude scale was invented by an ancient Greek astronomer named Hipparchus in about 150 BC He ranked the stars he could see in terms of their brightness, with 1 representing the brightest down to 6 representing the faintest. Modern astronomy has extended this system to stars brighter than Hipparchus' 1st magnitude stars and ones much, much fainter than 6. As it turns out, the eye senses brightness logarithmically, so each increase in 5 magnitudes corresponds to a …

…stars are suspected that could be 1000 times more massive than the sun, and, at the lower range, hot balls of gases may exist that are too small to initiate nuclear reactions. One possible such brown dwarf was first observed in 1987, and others have been detected since then. Star brightness is described in terms of magnitude. The brightest stars may be as much as 1,000,000 times brighter than the sun; white dwarfs are about 1000 times less bright.