220828 - NGC7000 "North America" nebula
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click image to enlarge
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ASTRO:
type=Emission nebula mag=4 const=Cygnus dist=2600 ly size=90 ly IMAGE: location=EB Driveway BrtlCls=4 moon=4%, WxGb exposure=DSLR OSC; 111x120s (3.7h), ISO1600, f/4.8 palette="HOO" EQUIPMENT: camera=Nikon D90 (mod) optics=ES102 w0.65x rdcr, F=464mm, f/4.55 (eff.) filter=Optolong L-Pro LPS mount=Celestron AVX guiding=Orion 60x240mm, ZWO ASi224MC SOFTWARE: acquisition=Stellarium, APT, PHD2, processing=PixInsight, RCAstro, PhotoshopCC, Lumenzia, APF-R |
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The North America Nebula (catalogued as NGC 7000, and Caldwell 20) is an emission nebula in the constellation Cygnus, close to the first-magnitude star Deneb which is located at the tip of the tail of the Swan and is its brightest star. Deneb is most notably at the head of the asterism (or common star pattern that is NOT a registered constellation with the IAU) called, "The Northern Cross" which almost completely encompasses the Cygnus constellation. The shape of the nebula resembles that of the continent of North America, complete with a prominent Gulf of Mexico.
The North America Nebula covers a region more than ten times the area of the full moon; but its surface brightness is low, so normally it cannot be seen with the unaided eye. Binoculars or a telescope with a large field of view (approximately 3°) will show it as a foggy patch of light under sufficiently dark skies. However, using an Ultra High Contrast (or " UHC") filter, which filters out some of the unwanted wavelengths of light pollution, it can be seen without magnification under dark skies. Its shape and reddish color come from the hydrogen-alpha (or "Hα") wavelength of light emission and shows up only in long-exposure photographs of the area like this one.
The North America Nebula covers a region more than ten times the area of the full moon; but its surface brightness is low, so normally it cannot be seen with the unaided eye. Binoculars or a telescope with a large field of view (approximately 3°) will show it as a foggy patch of light under sufficiently dark skies. However, using an Ultra High Contrast (or " UHC") filter, which filters out some of the unwanted wavelengths of light pollution, it can be seen without magnification under dark skies. Its shape and reddish color come from the hydrogen-alpha (or "Hα") wavelength of light emission and shows up only in long-exposure photographs of the area like this one.