2016 September 3 ~ M8, The Lagoon Nebula (and the star cluster NGC 6530)

******************************************************************************

Photographed at Algonquin Provincial Park, Ontario, Canada

between 21.19 and 21.53 EDT

(285 km by road north of Toronto)

* Altitude of M8 at time of exposures: 21°, decreasing to 19°

* Temperature 11° C.

 

* Total exposure time: 15 minutes

* 1200 mm focal length telescope

___________________________________________

 

Description:

 

Low in the northern hemisphere summer sky is the large Lagoon Nebula in the constellation Sagittarius (The Archer). The Lagoon (also known as Messier 8 or M8) is a favourite target of amateur astronomers with modest telescopes. The red colour - which the human eye can't detect - is the telltale sign of ionized hydrogen gas clouds.

 

From Wikipedia:

"The Lagoon Nebula ... is a giant interstellar cloud in the constellation Sagittarius. It is classified as an emission nebula and as an H II region.

 

The Lagoon Nebula was discovered by Giovanni Hodierna before 1654 and is one of only two star-forming nebulae faintly visible to the naked eye from mid-northern latitudes. Seen with binoculars, it appears as a distinct oval cloudlike patch with a definite core. In the foreground is the open cluster NGC 6530.

 

The Lagoon Nebula is estimated to be between 4,000-6,000 light-years 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) ... It also includes a funnel-like or tornado-like structure caused by a hot O-type star that emanates ultraviolet light, heating and ionizing gases on the surface of the nebula."

 

Embedded in the nebula - and just to left of its centre in this view - is the bright star cluster NGC 6530. Several dark globules are quite readily visible as well.

 

To see a wider angle view of this nebula and other adjacent objects, click here:

www.flickr.com/photos/97587627@N06/28874267555

__________________________________________

 

Nikon D810a camera body on Explore Scientific 152 mm (6") apochromatic refracting telescope, mounted on Astrophysics 1100GTO equatorial mount with a Kirk Enterprises ball head

 

Fifteeen stacked subframes; each frame:

ISO 3200; 1 minute exposure at f/8

(with LENR - long exposure noise reduction)

 

Subframes stacked in RegiStar;

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

******************************************************************************

Done