Dunlop's Globulars

[glenc]

James Dunlop saw these 36 globular clusters from his backyard in Parramatta NSW with his 9-inch speculum reflector in 1826.
He was the first person to see most of them.

NGC 104, NGC 362, NGC 1261, NGC 1851, NGC 2298
NGC 2808, NGC 3201, NGC 4372, NGC 4833, NGC 5139
NGC 5286, NGC 5824, NGC 5927, NGC 5986, NGC 6101
NGC 6139, NGC 6266, NGC 6316, NGC 6352, NGC 6362
NGC 6388, NGC 6397, NGC 6441, NGC 6496, NGC 6522
NGC 6541, NGC 6569, NGC 6584, NGC 6624, NGC 6637
NGC 6652, NGC 6681, NGC 6715, NGC 6723, NGC 6752
NGC 6809

For images of 35 Dunlop GC see:
http://picasaweb.google.com/dunlop1826/DunlopGlobularClusters
Images of NGC 6522 and NGC 6624 are not included, and 6380 is too faint for Dunlop to see.
The 4 faintest GC in his list are NGCs 2298, 5824, 6101 and 6139.

For more details on all the 158 MW GC see:
http://seds.lpl.arizona.edu/~spider/spider/mwgc/mwgc.html (http://seds.lpl.arizona.edu/%7Espider/spider/mwgc/mwgc.html)

[glenc]

I looked at 35 of these GC last night with a 12" dob, all except NGC 1261.
NGC 5824 and NGC 6101 make an interesting pair, 5824 is like a blurry star and pretty bright, 6101 is large and faint.

[programmer]

Cool, sounds like my next observing session if the sky ever clears in Melbourne, thanks Glen. How many do you think I could hit with my 10" from the burbs?

[glenc]

The 4 faintest are NGCs 2298, 6101, 6139 and 6496.
The rest should be OK from your place if you can escape the street lights.

[glenc]

Here are Dunlop's 1826 descriptions of NGC 6101 and 5824. They were made with a telescope that was equivalent to a modern 6.5" Newtonian.

D68=NGC6101 "A pretty large rather faint round nebula, about 3.5’ or 4' diameter, a little brighter in the middle. There is a very small nebula on the north preceding side joining the margin of the large nebula"

D611=NGC5824 "A very singular body resembling a star with a burr. The light is equal to that of a star of the 7th and 8th magnitude, and the diameter is not sensibly larger, with various magnifying powers. This has the appearance of a bright nucleus, surrounded by a strong brush of light; and the nebulosity surrounding the bright point has not that softness which nebulae in general possess. I consider this different from nebulae in general."

[glenc]

Last night I looked at 36 Dunlop objects, including 29 open clusters. I started with NGC 2516 and finished with NGC 4833.
The open cluster Trumpler 13 was interesting as it looks like a faint globular cluster. Dunlop described it as D308 "A very small round nebula, about 25” diameter, bright at the centre, nearly in a line between two very small stars. A star of the 6-7th magnitude is south following." James Dunlop found this 100 years before Robert Julius Trumpler put his name on it in 1930.

[glenc]

Melotte 105 is another interesting cluster that I saw last night. Dunlop describes it as "A rather bright nebula, about 2.5’ or 3’ long and 1' broad, in the form of a crescent, the convex side preceding; no condensation of the nebulous matter towards any point. This is easily resolvable into many stars of some considerable magnitude, arranged in pretty regular lines, with the nebula remaining, which is also resolvable into extremely minute stars. This is probably two clusters in the same line." (D271)
He discovered this when he started his catalog of 629 nebulae and clusters, on the first night, 27/4/1826.
Philibert Jacques Melotte cataloged it in 1915.