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glenc
14-10-2006, 08:36 AM
The galaxies below were selected from 736 GX with Vmag <= 11.5
Faint dwarf galaxies were not included.
The numbers below are NGC numbers.
Some statistics.

1. The brightest GX by magnitude in order are:
LMC
SMC
224 M31
598 M33
5128
3031 M81
253
5236 M83
5457 M101
55
4594 M104

2. The brightest GX by surface brightness (in this sample) in order are:
7176
IC 1029
4594 M104
4699
6438
5353
3366
4143
IC 4444
4800
278
3115

3. The largest GX in order are:
LMC
SMC
224 M31
598 M33
55
5457 M101
253
3031 M81
5128
205 M110

4. Some long narrow galaxies are:
5907 has the largest length to width ratio in this sample.
4244
5170
IC 5052
4565
4517
7090
55
4631
1560

5. Selected distances in million lyrs.
LMC 0.17
6822 1.6
224 M31 2.6
55 6.5
253 13
5236 M83 15
3623 M65 25
4594 M104 30
4486 M87 51
4406 M86 57
772 105

References
Third Reference Catalogue of Bright Galaxies (RC3) (de Vaucouleurs+ 1991)
The RC3 catalogue contains 23,011 galaxies
http://cdsweb.u-strasbg.fr/viz-bin/VizieR?-source=VII/155

When you have seen all of them try: ;)
Catalogue of Principal Galaxies (PGC) (Paturel+ 1989)
The PGC catalogue contains 77,141 galaxies.
http://cdsweb.u-strasbg.fr/viz-bin/VizieR?-source=VII/119

How many galaxies are there in the Universe?
The Hubble telescope is capable of detecting about 80 billion galaxies.
http://www.faqs.org/faqs/astronomy/faq/part8/section-4.html
That is about 12 galaxies for each person on earth!

Another site estimates there are 240 billion galaxies. :eyepop:
http://www.astronomycafe.net/qadir/q1120.html

Starkler
14-10-2006, 10:52 AM
Glen well done on providing some very useful reference info on the different classes of objects :thumbsup:

I personally would like to see this info in a series of pages in the resources or articles section, rather than slipping off the forum with the passage of time.

glenc
14-10-2006, 12:34 PM
When I have finished I will combine them onto one page.
Still plan to do PN, OC and BN.

mickoking
14-10-2006, 04:43 PM
Thats another great thread Glen :thumbsup: I didn't realise M31 is bigger than M33. The surface brightness ratings are particually interesting.

[1ponders]
14-10-2006, 04:47 PM
Cheers Glen, thanks for this. Saves me hunting down ones that will give a good size in the ED80 :thumbsup:

mattweather
15-10-2006, 02:35 PM
i guess it fake gals

glenc
04-11-2006, 05:32 AM
Just an update on the number of galaxies.
350 billion large galaxies.
7 trillion dwarf galaxies
http://www.atlasoftheuniverse.com/universe.html

That gives 3 times 10 to the power 22 stars = 30,000,000,000,000,000,000,000 stars.
The Sun is one of them.

CoombellKid
04-11-2006, 07:19 PM
Pretty hard for me to imagine that there isn't a planet or two+
orbiting some of these stars, with life on them.

regards,CS sunny days

Rob

glenc
05-11-2006, 05:12 AM
Maybe the number of stars is Avogadros number.
6exp23.