NGC 4565, also known as the Needle Galaxy, is the finest and brightest example of an edge-on spiral galaxy in the sky. It shines at magnitude +9.5 and therefore is bright enough to be seen with small telescopes. The galaxy is located in the constellation of Coma Berenices. Since positioned at the eastern edge of the sprawling naked eye Coma Star Cluster (Mel 111), it's easy to find.
NGC 4565 was discovered by William Herschel on April 6, 1785. It's number 38 in the Caldwell catalogue and is best seen from northern locations during the months of March, April and May. This spiral is physically large and similar in size to the Andromeda Galaxy (M31).
The Needle Galaxy is located only 3 degrees from the North Galactic Pole and less than 2 degrees east of star, 17 Comae Berenices (mag. +5.3). Along with other naked eye stars, 17 Comae Berenices is a member of the Coma Star Cluster, which also includes 12,13,14,16 and 21 Comae Berenices.
NGC 4565 is a challenging object to spot with 7x50 and 10x50 binoculars. Through an 80mm (3.1-inch) scope at high powers, it appears as a thin line of nebulosity with a hint of a central bulge. In total, this slither of light spans some 15.8 x 2.0 arc minutes of apparent sky. Since edge-on from our perspective, it does have a high surface brightness.
With larger scopes, the galaxy is a wonderful sight. A 200m (8-inch) instrument at high powers reveals a long needle of nebulosity. The nucleus appears bright and star like with a broad dust band running along its edge. Surrounding the nucleus is a round haze of light. Through even larger scopes, it's possible to tease out finer details in the dust lane. This galaxy is stunning and certainly one of the best deep-sky objects not included in the Messier catalogue.
NGC 4565 is 30 Million light-years distant. It has a spatial diameter of 140,000 light-years and is estimated to contain a trillion stars. Located 2 degrees north of NGC 4565 is another bright spiral, NGC 4559 (mag. +10.0).
NGC 4565 Data Table
|Object Type||Spiral Galaxy|
|Distance (light-years)||30 Million|
|RA (J2000)||12h 36m 21s|
|DEC (J2000)||+25d 59m 19s|
|Apparent Size (arc mins)||15.8 x 2.0|
|Number of Stars||1 Trillion|
|Notable Feature||Prominent example of an edge-on spiral galaxy|