NGC 4565

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NGC 4565
Needle Galaxy 4565.jpeg
NGC 4565 or Needle Galaxy
Observation data (J2000 epoch)
Constellation Coma Berenices
Right ascension 12h 36m 20.8s[1]
Declination +25° 59′ 16″[1]
Redshift 0.004103[1]
Helio radial velocity 1230 ± 5 km/s[1]
Distance 42.7 ± 12 Mly (13.1 ± 3.7 Mpc)[2]
53 ± 4 Mly (16.2 ± 1.3 Mpc)[3]
Apparent magnitude (V) 10.42[1]
Characteristics
Type SA(s)b?[1]
Apparent size (V) 15′.90 × 1′.85[1]
Other designations
UGC 7772,[1] PGC 42038,[1] Caldwell 38
See also: Galaxy, List of galaxies

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[2] in the constellation Coma Berenices.

This galaxy, appearing of 10th visual magnitude, sits perpendicularly to the Milky Way galaxy, being is almost directly above the North Galactic Pole.

It is known as the Needle Galaxy for its narrow profile.[4] First spotted in 1785 by William Herschel, it is one of the most famous examples of an edge-on spiral galaxy.[5] "Visible through a small telescope, some sky enthusiasts consider NGC 4565 to be a prominent celestial masterpiece Messier missed."[4]

Characteristics[edit]

NGC 4565 is a giant spiral galaxy more luminous than the Andromeda Galaxy.[6]

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.[7] 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.[8][8]

NGC 4565 has at least two satellite galaxies, one of which is interacting with it.[9]

It has a population of roughly 240 globular clusters, more than the Milky Way.[6]

NGC 4565 and apparently smaller NGC 4562, seen by the 24-inch telescope on Mt. Lemmon, USA.
A detailed view of part of the disc of the spiral galaxy NGC 4565 imaged by the Hubble Space Telescope.

References[edit]

  1. ^ a b c d e f g h i "Results for NGC 4565". NASA/IPAC Extragalactic Database. Retrieved 2006-10-12. 
  2. ^ a b "Distance Results for NGC 4565". NASA/IPAC Extragalactic Database. Retrieved 2010-05-02. 
  3. ^ Jensen, Joseph B.; Tonry, John L.; Barris, Brian J.; Thompson, Rodger I.; et al. (February 2003). "Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations". Astrophysical Journal. 583 (2): 712–726. arXiv:astro-ph/0210129Freely accessible. Bibcode:2003ApJ...583..712J. doi:10.1086/345430. 
  4. ^ a b NGC4565 at http://apod.nasa.gov/apod/ap040409.html
  5. ^ Spiral Galaxy NGC 4565 at http://www.eso.org/gallery/v/ESOPIA/Galaxies/phot-24a-05.tif.html
  6. ^ a b Globular Cluster Systems in Galaxies Beyond the Local Group
  7. ^ "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
  8. ^ a b Detection of a Distinct Pseudobulge Hidden Inside the ``Box-Shaped Bulge of NGC 4565
  9. ^ HALOGAS: H I Observations and Modeling of the Nearby Edge-on Spiral Galaxy NGC 4565

External links[edit]

Coordinates: Sky map 12h 36m 20.8s, +25° 59′ 16″