NGC 4889
THE COMA GALAXY CLUSTER


Combination of 4, 3 minute images.
Meade 416XTE CCD. 300mm f/6 newtonian telescope at prime focus.

Almost all observers are well aware of then Virgo cluster of galaxies. That huge swarm of over 1000 galaxies that straddles the Coma Berenices-Virgo region. However not so well known is that there is another equally large cluster in Coma Berenices known as The Coma Cluster or Abell Galaxy Cluster 1556. The main reason that this galaxy cluster is not so well known is that the cluster is nearly 10 times further away than the Virgo cluster, at a distance of over 400 million light years. This means that most of the members of the cluster are small and faint.

The brightest member is the giant eliptical galaxy NGC 4889. At magnitude 13, it is about the most distant galaxy visible in a small telescope, having been observed in telescopes as small a 5". Within 1.5 degrees of the centre of the cluster there are over 800 galaxies brighter than magnitude 16.5. While undoubtably many of these are background galaxies, the cluster is nontheless very rich.

Below are several maps to assist observers in locating this very distant object. The first map is a large scale map showing the general area around the cluster. The second chart shows an area of about 4 degrees and includes the cluster and the nearest bright star, beta comae. This is for use at the finder. The final charts are small-scale maps of the cluster showing ever fainter stars and is for use with the main telescope. The numbers alongside some of the stars are the magnitudes of those stars.

The photograph above shows the region around NGC 4889. Even this small region (about 13' x 8') there are more than 25 galaxies visible. Compare this image with the last chart. In the image NGC 4874 is just out of view on the right. The numbers alongside many of the galaxies are the number of the galaxy in the list below.



Wide field chart

Medium field chart

Narrow field chart

Narrow field chart

Below is a list of many of the galaxies shown in the above image and on the last map. This list gives the name of the galaxy, its position, magnitude, and size. Many of the fainter magnitudes are photographic and will appear brighter to the eye. How many objects from this list can you locate?


Number
NGC/IC
PGC
R.A.
Dec
Mag
Size
1
 NGC 4889 PGC 44715 13 00 08.1 +27 58 36 12.5 2.8'x2.2'
2
 NGC 4874 PGC 44628 12 59 35.7 +27 57 33 12.6 2.3'x2.3'
3
 NGC 4886 PGC 44698 13 00 04.5 +27 59 15 13.8 0.6'x0.6'
4
 IC 4051 PGC 44832 13 00 54.5 +28 00 27 14.2 1.0'x08'
5
 PGC 44644 12 59 39.7 +27 57 13 14.4 0.4'x0.2'
6
 NGC 4898 PGC 44736 13 00 17.8 +27 57 19 14.5 0.5'x0.5'
7
 NGC 4864 PGC 44566 12 59 13.2 +27 58 35 14.6 0.7'x0.7'
8
 NGC 4865 PGC 44578 12 59 19.9 +28 05 03 14.6 0.9'x0.5'
9
 NGC 4908 PGC 44828 13 00 51.6 +28 02 33 14.7 0.8'x0.6'
10
 NGC 4869 PGC 44587 12 59 23.4 +27 54 41 14.8 0.7'x0.7'
11
 PGC 44636 12 59 39.0 +27 59 10 14.8 0.4'x0.3'
12
 IC 4045 PGC 44818 13 00 48.7 +28 05 26 15.0 0.7'x0.4'
13
 NGC 4873 PGC 44621 12 59 32.8 +27 59 00 15.1 0.7'x0.5'
14
 NGC 4906 PGC 44799 13 00 39.8 +27 55 25 15.1 0.5'x0.5'
15
 NGC 4894 PGC 44732 13 00 16.5 +27 58 02 15.1 0.6'x0.3'
16
 NGC 4871 PGC 44606 12 59 30.0 +27 57 21 15.2 0.7'x0.5'
17
 PGC 44656 12 59 43.7 +27 09 40 15.2 0.4'x0.4'
18
 PGC 44771 13 00 28.4 +27 58 20 15.2 0.6'x0.3'
19
 IC 4041 PGC 44804 13 00 40.9 +27 59 47 15.3 0.5'x0.3'
20
 IC 4042 PGC 44808 13 00 42.8 +27 58 16 15.3 0.7'x0.5'
21
 IC 3973 PGC 44612 12 59 30.8 +27 53 02 15.4 0.8'x0.5'
22
 IC 4040 PGC 44789 13 00 37.9 +28 03 26 15.4 1.0'x0.3'
23
 NGC 4867 PGC 44568 12 59 15.3 +27 58 14 15.4 0.6'x0.5'
24
 NGC 4872 PGC 44624 12 59 34.1 +27 56 48 15.4 0.6'x0.4'
25
 NGC 4876 PGC 44658 12 59 44.4 +27 54 44 15.4 0.6'x0.4'
26
 NGC 4883 PGC 44682 12 59 56.0 +28 02 04 15.4 0.6'x0.4'
27
 PGC 44581 12 59 20.2 +27 53 09 15.4 0.5'x0.3'
28
 PGC 44763 13 00 28.0 +27 57 21 15.4 0.5'x0.3'
29
 PGC 44575 12 59 13.9 +28 04 34 15.6 0.7'x0.7'
30
 IC 4026 PGC 44749 13 00 22.1 +28 02 48 15.6 0.6'x0.5'
31
 IC 3998 PGC 44664 12 59 46.9 +27 58 25 15.6 0.6'x0.4'
32
 PGC 44849 13 00 59.3 +27 53 59 15.6 0.7'x0.3'
33
 NGC 4875 PGC 44640 12 59 37.9 +27 54 26 15.7 0.5'x0.4'
34
 IC 4021 PGC 44726 13 00 14.8 +28 02 28 15.9 0.4'
35
 PGC 44616 12 59 31.5 +28 02 47 15.9 0.8'x0.3'
36
 PGC 44716 13 00 09.1 +27 51 58 16.0 0.3'x0.2'
37
 IC 4012 PGC 44714 13 00 08.0 +28 04 42 16.0 0.4'x0.3'
38
 PGC 44662 12 59 40.9 +27 51 14 16.0 0.3'x0.2'
39
 IC 4011 PGC 44705 13 00 06.4 +28 00 14 16.1 0.4'
40
 PGC 44585 12 59 22.6 +27 53 48 16.3 0.5'x0.3'
41
 PGC 44809 13 00 42.9 +27 57 47 16.3 0.5'x0.3'
42
 PGC 44675 12 59 56.7 +27 55 47 16.4 0.6'x0.3'
43
 PGC 44723 13 00 12.9 +28 04 31 16.4 0.5'x0.3'
44
 PGC 44602 12 59 28.7 +28 02 25 16.5 0.5'x0.3'
45
 PGC 44707 13 00 06.1 +28 01 23 16.5 0.6'x0.3'
46
 PGC 44740 13 00 16.6 +28 03 47 16.5 0.5'x0.3'
47
 PGC 44815 13 00 44.6 +28 06 01 16.5 0.4'x0.1'
48
 PGC 44594 12 59 26.4 +27 59 53 16.6 0.3'x0.2'
49
 PGC 44649 12 59 42.3 +27 55 28 16.6 0.3'
50
 PGC 44597 12 59 25.3 +27 58 04 16.7 0.4'x0.2'
51
 PGC 44741 13 00 18.2 +27 56 12 16.7 0.4'


Mosiac of the Coma cluster. Each image is a combination of 4, 3 minute exposures.
Meade 416XTE CCD. 300mm f/6 newtonian at prime focus.


3 minutes exposure.
SBIG STL-1001E CCD. 20" f/6.8 Dall-Kirkham cassegrain telescope at prime focus.


Mosiac of 2 images. Each a combination of 5, 3 minute images unfiltered.
SBIG STL-1001E CCD. 20" f/6.8 Dall-Kirkham cassegrain telescope at prime focus.