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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.〔NGC4565 at http://apod.nasa.gov/apod/ap040409.html〕 First spotted in 1785 by Sir William Herschel (1738–1822), this is one of the most famous examples of an edge-on spiral galaxy.〔Spiral Galaxy NGC 4565 at http://www.eso.org/gallery/v/ESOPIA/Galaxies/phot-24a-05.tif.html〕 "Visible through a small telescope, some sky enthusiasts consider NGC 4565 to be a prominent celestial masterpiece Messier missed."〔 == Characteristics == NGC 4565 is a giant spiral galaxy more luminous than the Andromeda Galaxy〔(Globular Cluster Systems in Galaxies Beyond the Local Group )〕 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.〔"Intermediate-band surface photometry of the edge-on galaxy NGC 4565" at http://www.iop.org/EJ/article/1538-3881/123/3/1364/201272.text.html〕 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.〔(Detection of a Distinct Pseudobulge Hidden Inside the ``Box-Shaped Bulge'' of NGC 4565 )〕 NGC 4565 has at least two companion galaxies, one of which is interacting with it.〔(HALOGAS: H I Observations and Modeling of the Nearby Edge-on Spiral Galaxy NGC 4565 )〕 It has a population of roughly 240 globular clusters, more than the Milky Way.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「NGC 4565」の詳細全文を読む スポンサード リンク
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