Virgo Galaxy Cluster

The Nonet

Exposure:                   L = 70 min 1x1, RGB 20 min each
Date:                           April 1 & 2, 2009 .
Comments:                 A "nonet" in music is an ensemble of nine singers. This group of nine galaxies is also given that name. There are many more galaxies in this locale than nine, but the major ones are:

  1. 1.  The large elliptical galaxy in the upper center is M 86* (mag = 8.9).  Then starting at the top and going clockwise we have:

  2. 2.  Edge-on spiral galaxy NGC 4402 (mag. = 11.8).

  3. 3.  Elliptical galaxy M 84 (mag. = 9.2).   4. Between this and the center of the frame is small galaxy NGC 4387 (mag. = 12.0).

  4. 5.  Lying horizontally at the 5 o'clock position in the frame: Edge-on spiral galaxy NGC 4388 (mag. = 11.0).

  5. 6.  At 6 o'clock in the frame: Small, face-on spiral galaxy NGC 4413* (mag. = 11.9).

  6. 7.  Almost edge-on spiral galaxy NGC 4425 (mag. = 11.9).

  7. 8.  In the upper left corner are distorted spiral galaxy NGC 4438* (mag. = 10.0) also known as Arp galaxy 120. And

  8. 9.  Its companion spiral galaxy NGC 4435 which, together with its neighbor, 4438, are called "The Eyes". (Some writers erroneously call this pair the "Nonet". But obviously that term applies to the entirety of the nine member group not to just these two.)

Along the very bottom of the image are two tiny elliptical galaxies: On the left IC 3363 (mag. = 14.3) and on the right PGC 40636 (mag. = 15.8).

*Some of the galaxies shown in this image reportedly exhibit spectral blue-shift. For example M86 = -258 km/sec. There are several other such blue shifted galaxies in the Virgo cluster. For a listing see: http://arxiv.org/PS_cache/arxiv/pdf/1007/1007.1580v1.pdf  According to accepted theory these objects are approaching us rather than receding.

                               

Don Scott

The Holin A. Grotch Observatory

                            

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