It is located in the constellation of Vulpecula and is about 1,300 light years away from us. It has an apparent visual brightness of magnitude 7.5 and is about 6 arc-minutes in size. M27 was the first planetary nebula discovered by Charles Messier in 1864. The central star in M27 is a 14th magnitude extremely hot white dwarf with a temperature of 85,000 degrees Kelvin. Stars are born out of clouds of dust and hydrogen gas that collapse under the effects of gravity. When enough matter collects, the pressure causes the temperature to rise. After a while, if the pressure and temperature get great enough, a star begins to fuse hydrogen atoms together, giving off tremendous amounts of light and energy for billions of years. Eventually, a star will run out of fuel to burn. Its core will contract and the outer layers of its atmosphere will expand. The star becomes a red giant which is brighter, but cooler. After the red giant stage, the star will throw off its outer atmosphere and form a planetary nebula. The intense stellar wind given off by the hot central star causes the surrounding gasses that have been blown off to ionize and glow in the colors in our photographs. In the photo above, the primary color seen is the blue-green from Oxygen III emissions in the nebula, to which our camera is particularly sensitive. There is some red also from hydrogen-alpha emission, but because the camera has a long-wavelength filter, the red is not recorded very well in this short exposure. Image Data
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