BUBBLE NEBULA

The nebulae are the extended astronomical objects other than planets and comets in the open sky. Bubble Nebula is a stellar wind from a hot massive star present in the center causing it to glow. This New General Catalogue is 7635. It looks delicate and diameter is 7 light years. It is several hundred thousand times luminous and 45 times massive than our sun. Fascinating bubble nebula and  associated cloud complex lie at 7100 light years from earth in constellation Cassiopeia. The surface of the bubble's shell expands outward that gives an idea that dense region of cold gas on one side of the bubble. This asymmetry makes the star appear dramatically off-center from the bubble. The blue light indicates the oxygen, green for hydrogen and red for nitrogen. Bubble Nebula is one of the three shells surrounding the massive star. In the image, the magenta like threads are the remnants of the supernova that occurred thousands of years ago. The Bubble Nebula was discovered in 1787 by William Herschel, a prominent British astronomer.