NGC4565 Needle Galaxy

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2014/05/25 - This is our second light of our robotic remote setup. It took a while to gather all the data, but finally after two months I can present our spring object NGC4565. Weather wasn't always that good, and I had to reject lot of failed lights because of the moon and clouds. But we still gathered a nice set of data.

NGC 4565 (also known as the Needle Galaxy or Caldwell 38) is an edge-on spiral galaxy about 30 to 50 million light-years away in the constellation Coma Berenices. The 10th magnitude galaxy sits perpendicular to our own Milky Way galaxy and is almost directly above the North Galactic Pole (in the same way Polaris is located above the Earth's North Pole). It is known as the Needle Galaxy for its narrow profile. First spotted in 1785 by Sir William Herschel (1738–1822), this is one of the most famous examples of an edge-on spiral galaxy. "Visible through a small telescope, some sky enthusiasts consider NGC 4565 to be a prominent celestial masterpiece Messier missed."

NGC 4565 is a giant spiral galaxy more luminous than the Andromeda Galaxy and it has been proposed that if it were viewed face-on, it would be the most spectacular of the galaxies of its type in the nearby Universe. Much speculation exists in the literature as to the nature of the central bulge. In the absence of clear-cut dynamical data on the motions of stars in the bulge, the photometric data alone cannot adjudge among various options put forth. However, its exponential shape suggested that it is a barred spiral galaxy. Subsequent studies with the help of the Spitzer Space Telescope not only confirmed the presence of a central bar but also showed a pseudobulge within it as well as an inner ring. NGC 4565 has at least two companion galaxies, one of which is interacting with it. It has a population of roughly 240 globular clusters, more than the Milky Way.

Object information
Name : NGC4565 Needle Galaxy
Type : Galaxy
Constellation : Coma Berenices
Distance : 42.700K light-year
Apparent dimensions : 15'.90 x 1'.85
Apparent magnitude : 10.42

Image information
Image date : 2014/05/25, 2014/05/18, 2014/04/23, 2014/04/19, 2014/04/05, 2014/03/29, 2014/03/27
Right ascension : 12:36:20.413
Declination : 25°12' 0.00"
Focal length : 1687.01 mm
Focal ratio : f/6.64
Image resolution : 0.660 arcsec/pixel
Field of view : 35' 52.9" x 27' 5.9"
Sky quality : 21.50 mag/arcsecond2
Sensor temperature : -20°C
Light frames : 21 hours total exposure time
42x 900 sec. luminance unbinned
8x 1800 sec. red unbinned
6x 1800 sec. green unbinned
7x 1800 sec. blue unbinned
Image acquisition with ACP Observatory Control Software, ACP Scheduler and Maxim DL
Auto-guiding with Maxim DL
Auto-focusing with FocusMax
Bias frames : 100x unbinned
Dark frames : None
Flat frames : 24x luminance unbinned
24x RGB unbinned
Automated sky twilight flats with ACP
Processing : PixInsight for calibration, alignment and integration.
Adobe Photoshop CS6 for final touch.

Equipment information
Telescope : Orion Optics 10" ODK
Corrector : None
Focuser : Baader SteelTrack with SteelDrive
Mount : Mesu Mount 200 with Sidereal Technology SiTech Controller
Camera : QSI 683wsg-8 cooled CCD camera with Kodak KAF-8300 sensor and Off Axis Guide (OAG) port
Guidecamera : Starlight Xpress Lodestar autoguider
Filters : Baader LRGB
Observatory site :, Hautes-Alpes, France