NGC 6193
At its centre are two O class multiple star systems within 10" of each other, and a probable binary B0 giant. These are very hot large stars. They are part of the multiple star system HD 150136. There are four stars which are each 36 to 63 times more massive than the Sun, 6 to ten times hotter, and each is more than 10,000 times as bright (luminosity) as the Sun.