2016 Sept. 24 ~ Messier 51, the Whirlpool Galaxy

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Photographed at Algonquin Provincial Park, Ontario, Canada, between 21.38 and 22.12 EDT

(285 km by road north of Toronto)

* Altitude of M51 at time of exposures: 23°, decreasing to 19°

* Temperature 8° C.

 

* Total exposure time: 16 minutes

* 2483 mm focal length telescope

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Located just south of the end star of the Big Dipper in the constellation Ursa Major (The Great Bear) (but actually across the border in the constellation Canes Venatici - The Hunting Dogs) the Whirlpool galaxy is a favourite target of amateur astronomers, especially in the northern hemisphere spring and early summer.

 

M51, which has a black hole at its core, is about 35% of the size and mass of our own Milky Way galaxy. It was the first galaxy to be identified as spiral in structure. The two portions of this galaxy interact with each other; the smaller satellite portion is named NGC 5195. The distance to this galaxy is still quite uncertain; estimates are between 15 and 35 million light years. By contrast, the great Andromeda Galaxy lies a mere 3 million light years from us.

 

Click here to see the equipment used to photograph this galaxy:

www.flickr.com/photos/97587627@N06/29939255555

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Nikon D810a camera body at prime focus of Meade 30 cm (12") LX-850 Schmidt-Cassegrain telescope, mounted on Astrophysics 1100GTO equatorial mount

 

Sixteen stacked frames; each frame:

2483 mm focal length; ISO 8000; 60 seconds exposure at f/8, unguided

(with LENR - long exposure noise reduction)

 

Subframes stacked in RegiStar;

Processed in Photoshop CS6 (brightness, contrast, levels, colour balance)

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Done