2022 June 25 ~ M8, the Lagoon Nebula, and nearby globular star clusters in Sagittarius [WITH LABELS]

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Photographed at Algonquin Provincial Park, Ontario, Canada

between 02.24 and 02.44 EDT

(285 km by road north of Toronto)

* Altitude of centre of frame at time of exposures: ~12°

* Temperature 14° C.

 

* Total exposure time: 10 minutes

* 660 mm focal length telescope

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Description:

 

North is to the upper right in this image, which contains several objects of note.

 

M8, the Lagoon Nebula, with embedded star cluster NGC 6530 (right side of the frame)

 

One of the most prominent, large, bright and well known nebulae in the sky is the Lagoon Nebula (M8), which is a favourite target of amateur astronomers with modest telescopes.

 

From Wikipedia: "The Lagoon Nebula ... is a giant interstellar cloud ... classified as an emission nebula and as an H II region. [It] was discovered by Giovanni Hodierna before 1654 and is one of only two star-forming nebulae faintly visible to the eye from mid-northern latitudes. Seen with binoculars, it appears as a distinct oval cloudlike patch with a definite core. Within the nebula is the open cluster NGC 6530.

 

The Lagoon Nebula is estimated to be between 4,000-6,000 light-years away from the Earth. In the sky of Earth, it spans 90' by 40', which translates to an actual dimension of 110 by 50 light years. ... The nebula contains a number of Bok globules (dark, collapsing clouds of protostellar material), the most prominent of which have been catalogued by E. E. Barnard as B88, B89 and B296."

 

IC 4678 (directly above M8)

 

This is a tiny nebula composed of emission (pink) and reflection (blue) components.

 

NGC 6544 (near centre of frame)

 

This is a small globular star cluster of magnitude ~7.3, lying at a distance of 9,000-10,00 light years from us..

 

NGC 6553 (left edge of frame, just below centre)

 

This is a globular star cluster of magnitude ~8.@, with an unusually low star concentration even at its centre, and lying about 19,600 LY from our solar system. Studies show that it underwent two distinct periods of star formation, resulting in two populations of stars with differing compositions, especially in sodium and aluminum.

 

For a version of this photo WITHOUT LABELS, click on the LEFT side of your screen, or click here:

www.flickr.com/photos/97587627@N06/52229327008

 

To see a wider angle view this and other adjacent nebulae, photographed in Australia in Sept. 2019, click here:

www.flickr.com/photos/97587627@N06/49183970671

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Technical information:

 

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

 

Ten stacked frames; each frame:

660 mm focal length

ISO 2500; 1 minute exposure at f/5.2; unguided

With long exposure noise reduction

 

Subframes stacked in RegiStar;

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

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Done