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RJ901

New General Catalog Object Analysis

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At the intersection of boredom, astronomy and excel lies my analysis of the objects within the NGC (sorry if this is old news). I made these tables using the data from the NGC/IC Project. It may help in further organizing your observational data, or planning, it might not, but it's kind of neat to see the breakdown by objects within the catalog (and it was fun to put together). Let me know if you catch any errors and I can update!

-Rick

Some interesting findings:

  1. I knew there were a bunch of galaxies in the NGC, just was not aware that 80% of all the existing, non-duplicate objects were galaxies
  2. There are more Double Stars in the NGC than Planetary Nebulae
  3. 7840 NGC entries, but only 5724 unique and existent objects (maybe 5723, depending on NGC 1990)
  4. 234 Entries are duplicates (or triplicates)
  5. The only duplicated entries are of galaxies
  6. There are 82 entries for which objects do not actually exist
  7. 83 is probably the real count if you say NGC 1990 does not exist
  8. January-April is a great time for open clusters
  9. June-August is a great time for globulars
  10. Any month is a great month for galaxies
  11. July and August are great for planetary nebulae
  12. 257 NGC objects are stars, doubles stars or triple stars
  13. Triples, Doubles and Single Stars are fairly evenly distributed across the catalog

Total Objects in the catalog by Type:

NGC Obect Type # of NGC Entries Duplicated Entries # of Unique NGC Objects % of Total % of Existing Objects Most Entries by Type within One NGC Range (Ex: 1-999 or 3000-3999) NGC Range with Most Objects by Type NGC Range with Second Most Count of the Second Most Entries by Type
Gxy 6271 234 6037 79.4% 80.2% 890 4000-4999 5000-5999 875
OC 678 0 678 8.9% 9.0% 245 2000-2999 1000-1999 154
GC 142 0 142 1.9% 1.9% 73 6000-6999 1000-1999 30
Star 115 0 115 1.5% 1.5% 23 1-999 4000-4999 18
Neb 111 0 111 1.5% 1.5% 47 2000-2999 1000-1999 31
Double Star 106 0 106 1.4% 1.4% 17 6000-6999 1-999 13
PN 98 0 98 1.3% 1.3% 49 6000-6999 2000-2999 14
OC+Neb 89 0 89 1.2% 1.2% 44 1000-1999 2000-2999 17
Ast 69 0 69 0.9% 0.9% 19 6000-6999 2000-2999 18
Triple Star 36 0 36 0.5% 0.5% 9 2000-2999 1-999 3
GxyCld 22 0 22 0.3% 0.3% 11 5000-5999 1-999 0
MWSC 8 0 8 0.1% 0.1% 8 6000-6999 N/A 0
SNR 6 0 6 0.1% 0.1% 5 6000-6999 1000-1999 1
HIIRgn 6 0 6 0.1% 0.1% 3 4000-4999 3000-3999 2
Neb?* 1 0 1 0.0% 0.0% 1 1000-1999 N/A 0
Nonexistent 82 0 0 1.1% ---- 19 1000-1999 7000-7840 17
Total 7840 234 7524            

Neb? *refers to NGC 1990

Objects by Type and Position within the Catalog:

NGC Number Galaxy Galaxy Cloud Nebula Questionable Nebula Open Cluster and Nebula Open Cluster Globular Cluster Planetary Nebula Super Nova Remant HII Region Milky Way Star Cloud Triple Star Double Star Star Asterism Nonexistent
1-999 834 6 4 0 12 49 8 4 0 0 0 6 16 23 5 8
1000-1999 646 0 31 1 44 154 30 4 1 0 0 3 13 13 10 19
2000-2999 596 4 47 0 17 245 5 14 0 1 0 9 12 17 18 8
3000-3999 873 1 8 0 2 21 1 7 0 2 0 3 15 10 0 7
4000-4999 890 0 0 0 0 12 5 2 0 3 0 2 5 18 3 7
5000-5999 875 11 1 0 0 28 15 7 0 0 0 2 14 11 2 5
6000-6999 634 0 15 0 12 120 73 49 5 0 8 6 17 6 19 11
7000-7840 689 0 5 0 2 49 5 11 0 0 0 5 14 17 12 17
Total 6037 22 111 1 89 678 142 98 6 6 8 36 106 115 69 82

 

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That's interesting, thanks. I bought Bratton's Herschel Objects book and was similarly staggered by quite how many of them are galaxies.

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On 3/8/2018 at 16:38, Hungrymark said:

That's interesting, thanks. I bought Bratton's Herschel Objects book and was similarly staggered by quite how many of them are galaxies.

It’s crazy, and makes me want to move to darkest wilds to be able to see all of the faint ones, but the wife will have none of that!

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It makes sense, when I think about it. Daft really. Of all the universe that is visible from here, of course the most visible objects are those massive things with billions if stars in them, but even so, blimey...

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Some Nice Excel work there. Once all those galaxies were considered to be nebulas within the milky way :happy11:.

I`m not quite sure how this structure will help me organising data (personal honest opinion :happy11:), to me its more of a fun fact overview.

 

As of Your conclusions :

I think Your findings are more suitable for observeres living far more South than those of us living in the Northern part of Europe:

On ‎06‎.‎03‎.‎2018 at 20:54, RJ901 said:
  • June-August is a great time for globulars
  • Any month is a great month for galaxies
  • July and August are great for planetary nebulae

For me May, June and first 2/3 of August is only decent for planets and some doubles. The 'night' sky is Incredible Bright.

On ‎06‎.‎03‎.‎2018 at 20:54, RJ901 said:

January-April is a great time for open clusters

In general open clusters (not referring to NGC OC`s only) are quite evenly spread along the galactic equator so any season (Sep-Apr) is a good OC season.

For me anyways.

 

Just my thoughts. But you certainly have motivated me to pick up Excel as an astronomy tool again, so thank you for posting :happy11:.

Regards

Rune

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very interesting post, thanks for sharing...clear skies!

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On 3/10/2018 at 10:31, Pondus said:

more suitable for observeres living far more South than those of us living in the Northern part of Europe:

Great catch; I should have noted there would be a shift in time due to latitudinal differences. As a reference, I observe from 35.1N. Thanks!

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Fascinating analysis considering I'd never given the subject much thought!

Thanks for sharing your work.

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