Not so long time ago Saint Valentine’s Rosette appeared in my blog. A few days later I pictured a little bit of RGB light to this frame, so it is now more colorful. In the crop of the Rosette center you can see some star colors. The bright white-blue giants in the nebula center are the NGC2244 young open cluster stars. They are about 5200 light years away, and still seems to be as bright as the yellow star to the left and down of the center. But the yellow star is 12 Mon, and is only 560 light years away, so ten times closer. The yellow stars has surface temperature about 4000-5000K, oranges are in the range 2500-4000K, and there are also few pure red stars that are even colder. On the other side are blueish monsters with surface temperature 40000K and more. And this is only surface temperature – inside the stars there are termonuclear reactions running and there is a multimillion Kelvins hell.
So blue is hot 🙂
And the full frame: