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M33_Triangulum_Galaxy
The Triangulum Galaxy (known as Messier 33 or NGC 598) is a beautiful large spiral galaxy in the constellation of Triangulum. It can be (barely) seen with the unaided eye as a faint small smudge only under a truly dark, transparent sky. It is thus one of the most distant objects visible to the unaided eye, since its distance is calculated to be about 3 million light-years. However and due to its relatively large apparent size (almost as large as the area covered by four full Moons), it has a low surface brightness and therefore it is a difficult object to observe under less than ideal conditions.
M33's loosely-wound spiral arms are filled with numerous reddish HII regions (emission nebulae of ionized hydrogen), as well as bluish clouds of young stars. Many of them have their own NGC numbers, the most prominent being NGC 604 (visible at the lower left of the spiral at 8 o' clock position from the nucleus). NGC 604 has a diameter of nearly 1,500 light-years and is estimated that it contains at least 200 newly-formed hot stars.
The galaxy was probably discovered in the 17th Century by Giovanni Batista Hodierna and rediscovered later in 1764 by Charles Messier, who gave it the catalog name M33. It was among the first "Nebulae" identified as extragalactic objects and it was E. Hubble that measured its distance using pulsating stars known as Cepheids, that placed it well outside our own Milky Way.
M33 is the third-largest galaxy of the Local Group, after the Andromeda Galaxy and our own Milky Way, with an estimated diameter of 50,000 light-years, about half the size of the Milky Way. Some astronomers believe that M33 may be a remote but gravitationally bound companion of the Andromeda galaxy.
Image Details:
Telescope: Orion EON ED 80/500 refractor
Mount: Modified Vixen Sphinx (NexSXW)
Camera: Canon EOS 20Da
Light frames: 34 x 3 mins (total: 102 mins), ISO 1600, Daylight WB
Support frames: Darks, Bias
Guiding: Skywatcher 80/400 refractor, Skywatcher Synguider autoguider
Date & Location: 16/10/2018 - Chalkidiki, Greece
Processing: DSS 4.1.1, Adobe Photoshop CS6 with Astronomy Tools Actions Set (spikes added to brightest stars)
M33_Triangulum_Galaxy
The Triangulum Galaxy (known as Messier 33 or NGC 598) is a beautiful large spiral galaxy in the constellation of Triangulum. It can be (barely) seen with the unaided eye as a faint small smudge only under a truly dark, transparent sky. It is thus one of the most distant objects visible to the unaided eye, since its distance is calculated to be about 3 million light-years. However and due to its relatively large apparent size (almost as large as the area covered by four full Moons), it has a low surface brightness and therefore it is a difficult object to observe under less than ideal conditions.
M33's loosely-wound spiral arms are filled with numerous reddish HII regions (emission nebulae of ionized hydrogen), as well as bluish clouds of young stars. Many of them have their own NGC numbers, the most prominent being NGC 604 (visible at the lower left of the spiral at 8 o' clock position from the nucleus). NGC 604 has a diameter of nearly 1,500 light-years and is estimated that it contains at least 200 newly-formed hot stars.
The galaxy was probably discovered in the 17th Century by Giovanni Batista Hodierna and rediscovered later in 1764 by Charles Messier, who gave it the catalog name M33. It was among the first "Nebulae" identified as extragalactic objects and it was E. Hubble that measured its distance using pulsating stars known as Cepheids, that placed it well outside our own Milky Way.
M33 is the third-largest galaxy of the Local Group, after the Andromeda Galaxy and our own Milky Way, with an estimated diameter of 50,000 light-years, about half the size of the Milky Way. Some astronomers believe that M33 may be a remote but gravitationally bound companion of the Andromeda galaxy.
Image Details:
Telescope: Orion EON ED 80/500 refractor
Mount: Modified Vixen Sphinx (NexSXW)
Camera: Canon EOS 20Da
Light frames: 34 x 3 mins (total: 102 mins), ISO 1600, Daylight WB
Support frames: Darks, Bias
Guiding: Skywatcher 80/400 refractor, Skywatcher Synguider autoguider
Date & Location: 16/10/2018 - Chalkidiki, Greece
Processing: DSS 4.1.1, Adobe Photoshop CS6 with Astronomy Tools Actions Set (spikes added to brightest stars)