2018 Oct. 5 ~ Sh2-131, IC 1396 and the Elephant's Trunk Nebula in Cepheus

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Photographed at Algonquin Provincial Park, Ontario, Canada, between 00.37 and 01.12 EDT

(285 km by road north of Toronto)

* Altitude of nebula at time of exposures: 63-58°

* Temperature 2° C.

 

* Total exposure time: 15 minutes

* 660 mm focal length telescope

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Description:

 

This huge ionized hydrogen gas cloud lies about 2,400 light years from our solar system. The nebula itself is named Sharpless 131; the large open cluster of stars near its centre is cataloged as IC 1396 or Trumpler 37. Below and to the right of centre is a small, prominent globule that is often referred to as the "Elephant's Trunk Nebula" (IC 1396a), and is an active star-forming region.

 

Here is another view of this object, made with a slightly smaller telescope almost exactly one year ago:

www.flickr.com/photos/97587627@N06/36698969403

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Technical information:

 

Nikon D810a camera body on Tele Vue 127is (127 mm - 5" - diameter) apochromatic astrograph, mounted on Astrophysics 1100GTO equatorial mount

 

Fifteen stacked subframes; each frame:

ISO 8000; 1 minute exposure at f/5.2, unguided

(with LENR - long exposure noise reduction)

 

Subframes stacked in RegiStar;

Processed in Photoshop CS6 (levels, brightness / contrast, bright star flare reduction)

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Done