2017 Sept. 17 ~ NGC 7000, the North America Nebula

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Photographed at Algonquin Provincial Park, Ontario, Canada

between 01.46 and 02.19 EDT

(285 km by road north of Toronto)

* Altitude of nebula at time of exposures: 53°

* Temperature 13° C.

 

* Total exposure time: 16 minutes

* 540 mm focal length telescope

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Description:

 

Visually with the unaided eye, or in binoculars or a telescope, the distinctively-shaped North America Nebula appears as a large but faint white cloud in the middle of our Milky Way galaxy. The digital camera sensor, however, reveals the red glow of ionized hydrogen gas.

 

This nebula is 1,600 light years distant from our solar system. Clouds of dark gas lie between us and the nebula, blocking the light behind and creating the apparent shape of the nebula.

 

For a wider angle view of this nebula - photographed with a telephoto lens at the end of July this year - that also shows the adjacent Pelican Nebula - click here:

www.flickr.com/photos/97587627@N06/35952320980

 

... and for an even wider angle view of the constellation Cygnus (The Swan), including the North America Nebula and other hydrogen gas clouds, also made in July, click here:

www.flickr.com/photos/97587627@N06/35914900410

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Technical information:

 

Nikon D810a camera body on Teleview 101is (4") apochromatic refracting telescope, mounted on Astrophysics 1100GTO equatorial mount

 

Sixteen stacked subframes; each frame:

ISO 8000; 1 minute exposure at f/5.4, unguided

(with LENR - long exposure noise reduction)

 

Subframes stacked in RegiStar;

Processed in Photoshop CS6 (levels, brightness / contrast, only moderately competent star masking)

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Done