2020 June 14 ~ M24, the Sagittarius Starcloud
***************************************************************************
Photographed at Algonquin Provincial Park, Ontario, Canada
(285 km by road north of Toronto)
between 01.46 and 02.03 EDT
* Altitude of starcloud at time of exposures: ~26°
* Temperature 4° C.
* Total exposure time: 8 minutes
* 660 mm focal length telescope
___________________________________________
Description:
Perhaps the most unusual and uncharacteristic object in Charles Messier's catalog of non-stellar objects is the M24 starcloud. Messier's other objects are easily identified galaxies, planetary nebulae, bright nebulae and star clusters. This object is a large, amorphous, extended cloud of stars that has a very imprecise boundary.
From Wikipedia: "The Sagittarius Star Cloud (also known as Delle Caustiche, Messier 24, IC 4715) is a star cloud in the constellation of Sagittarius, approximately 600 light years wide, which was discovered by Charles Messier in 1764. It is sometimes known as the Small Sagittarius Star Cloud to distinguish it from the Great Sagittarius Star Cloud located to the north of Gamma Sagittarii and Delta Sagittarii.
The stars, clusters and other objects comprising M24 are part of the Sagittarius or Sagittarius-Carina arms of the Milky Way galaxy. Messier described M24 as a "large nebulosity containing many stars" and gave its dimensions as being some 1.5° across. Some sources, improperly, identify M24 as the faint cluster NGC 6603.
M24 fills a space of significant volume to a depth of 10,000 to 16,000 light-years. This is the most dense concentration of individual stars visible using binoculars, with around 1,000 stars visible within a single field of view."
For a version of this photo WITH LABELS, click on the RIGHT side of your screen, or click here:
www.flickr.com/photos/97587627@N06/50008835702
For a very similar view of this region photographed in October 2019 from the Outback of Australia, click here:
www.flickr.com/photos/97587627@N06/49003545466
___________________________________________
Technical information:
Nikon D810a camera body on Tele Vue 127is (127 mm - 5" - diameter) apochromatic astrograph, mounted on Astrophysics 1100GTO equatorial mount
Eight stacked frames; each frame:
660 mm focal length
ISO 3200; 1 minute exposure at f/5.2; unguided
Subframes registered in RegiStar;
Stacked and processed in Photoshop CS6 (brightness, contrast, levels, colour balance, colour saturation)
***************************************************************************
2020 June 14 ~ M24, the Sagittarius Starcloud
***************************************************************************
Photographed at Algonquin Provincial Park, Ontario, Canada
(285 km by road north of Toronto)
between 01.46 and 02.03 EDT
* Altitude of starcloud at time of exposures: ~26°
* Temperature 4° C.
* Total exposure time: 8 minutes
* 660 mm focal length telescope
___________________________________________
Description:
Perhaps the most unusual and uncharacteristic object in Charles Messier's catalog of non-stellar objects is the M24 starcloud. Messier's other objects are easily identified galaxies, planetary nebulae, bright nebulae and star clusters. This object is a large, amorphous, extended cloud of stars that has a very imprecise boundary.
From Wikipedia: "The Sagittarius Star Cloud (also known as Delle Caustiche, Messier 24, IC 4715) is a star cloud in the constellation of Sagittarius, approximately 600 light years wide, which was discovered by Charles Messier in 1764. It is sometimes known as the Small Sagittarius Star Cloud to distinguish it from the Great Sagittarius Star Cloud located to the north of Gamma Sagittarii and Delta Sagittarii.
The stars, clusters and other objects comprising M24 are part of the Sagittarius or Sagittarius-Carina arms of the Milky Way galaxy. Messier described M24 as a "large nebulosity containing many stars" and gave its dimensions as being some 1.5° across. Some sources, improperly, identify M24 as the faint cluster NGC 6603.
M24 fills a space of significant volume to a depth of 10,000 to 16,000 light-years. This is the most dense concentration of individual stars visible using binoculars, with around 1,000 stars visible within a single field of view."
For a version of this photo WITH LABELS, click on the RIGHT side of your screen, or click here:
www.flickr.com/photos/97587627@N06/50008835702
For a very similar view of this region photographed in October 2019 from the Outback of Australia, click here:
www.flickr.com/photos/97587627@N06/49003545466
___________________________________________
Technical information:
Nikon D810a camera body on Tele Vue 127is (127 mm - 5" - diameter) apochromatic astrograph, mounted on Astrophysics 1100GTO equatorial mount
Eight stacked frames; each frame:
660 mm focal length
ISO 3200; 1 minute exposure at f/5.2; unguided
Subframes registered in RegiStar;
Stacked and processed in Photoshop CS6 (brightness, contrast, levels, colour balance, colour saturation)
***************************************************************************