My first image with my new 14.5" RCOS Ritchey-Chretien telescope and SBIG large format STL11000 camera.
M27, or the Dumbbell Nebula, is one of the most prominent “planetary nebulae” in the heavens and was the first ever discovered (by Charles Messier, in the 18th century). A planetary nebula is the outer atmosphere of a star that is exploded outward when the star's sudden collapse into a white dwarf is abruptly halted by the resistive force of electron degeneracy (electrons cannot occupy the same quantum state). We are seeing the “shell” of the star that is blowing outward as a result of the intense radiation emitted by a small, white dwarf star in the center.
Meticulous examination of 19th and early 20th century photographic plates shows that M27 is expanding at a rate of several miles per second. As planetary nebulae continue to expand, they become larger and dimmer, meaning that they can be seen for only a relatively small window of time (up to 50,000 years). But, because planetary nebulae represent the final stage in the life of stars of up to 3 solar masses, they are common enough that there always are some visible.
M27 is about 4 light years (25 trillion miles) in diameter, or roughly 1,200 times the distance between the Sun and Pluto. It is remarkable to think of a star's outer layers being dispersed over an area so large.
The prominent blue-green color is caused by the emission of photons as hydrogen electrons that were boosted into the fourth energy orbit (n4) by the intense radiation of the central white dwarf star immediately release that energy as they cascade down to the second energy level (n2). The photons released by electrons making this transition have a wavelength that the human eye sees as blue-green light. The red color is caused by photons emitted by excited electrons descending from the third energy level (n3) to n2. The wavelengths of these photons are seen as red by the human eye. Notice that the red coloration is farthest from the central white dwarf. This is visual proof that the photons at this distance are not energetic enough to bump electrons up to the fourth energy level.
The "Dumbbell Nebula" in Vulpecula
Date Taken:July 13, 2007
Location Taken: Conditions of Location:FWHM 2.25
Equipment Used:14.5" Ritchey-Chretien telescope, SBIG STL11000 CCD camera, Astrodon RGB filters, TCC, PIR, remote guide head used with Takahashi Sky90 for autoguiding, T-Point used for polar alignment (required for each imaging session due to my portable setup).
Processing Used:11 x 100 seconds LRGB, guided, processed in Maxim DL and Photoshop (total exposure 75 minutes)
Distance from Location:1,200 light years
Constellation:Vulpecula (the "fox")
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Like your pics, have liked astronomy all my life. What telescope do you use? I noticed some of the pics taken in Australia, do you go there often? thanks, Randy.