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glenc
25-12-2008, 07:17 AM
Nicolas Lacaille made the first catalogue of southern clusters and nebulae.
He made his catalogue seven years before Messier started his famous catalogue.

The Frenchman Abbe Nicolas-Louis de la Caille (1713-1762) arrived at Cape Town, South Africa on April 19, 1751. During the next two years he made a catalogue of 9,776 stars that included 42 nebulae and clusters. Lacaille discovered the nebulae and clusters between August 23, 1751 and July 18, 1752. He divided his list of nebulae and clusters into three parts; nebulae without stars, nebulae with stars, and clusters. There are 14 objects in each part. Today the 42 Lacaille objects are classified as 23 open clusters, 7 globular clusters, 4 diffuse nebulae and one galaxy. There are no planetary nebulae and the other 7 objects are asterisms or stars. Messier later included seven Lacaille objects in his catalogue, namely: M4, M6, M7, M8, M22, M55 and M83.
The remaining Lacaille objects were too far south for Messier to see. Lacaille was the first person to make a list of southern non-stellar objects. His list included 22 new objects. It was to be 74 years before James Dunlop made the next search for southern clusters and nebulae.

glenc
25-12-2008, 07:39 AM
Here are images of all the 42 Lacaille clusters and nebulae.
http://picasaweb.google.com.au/dunlop1826/LacailleSClustersAndNebulae#

The Lacaille catalogue can be found at: http://www.maa.clell.de/Messier/E/Xtra/History/lacaille.html

The images are all 56' x 56' except two images (2546/vBH7 and 3372) are 112' x 112'.
All images were made using www.wikisky.org (http://www.wikisky.org)

Argonavis
26-12-2008, 09:20 AM
For bonus points, please give details of the instrumnet(s) used, their aperture, focal length and maker.

GrampianStars
26-12-2008, 06:51 PM
Here's a visual history tour for Auotostar equipped scopes :thumbsup:
I put together today my first

glenc
26-12-2008, 06:57 PM
Thanks Robert. Lacaille used a 0.5" aperture refractor.

Babalyon 5
26-12-2008, 07:31 PM
You mean 12.5mm?? Wow that's as small as an eyepiece!! Incredible he saw anything at all!!:eyepop:

GrampianStars
26-12-2008, 07:42 PM
:D "O"light pollution back then :whistle:

glenc
26-12-2008, 07:56 PM
The object glass of Lacaille's telescope had a focal length of 712 mm its aperture was 13.5 mm. The focal length of the eyepiece was 88 mm to give the telescope an extended field, very clear, and free from parallaxes at its edges. The field was almost 3 degrees. This gave eight times magnification.

ngcles
26-12-2008, 08:58 PM
Hi Glen & All,

I know I tend to have a few wise-cracks at Lacaille's expense from time to time (I guess it's easy as he is long molderin' in the ground) but he really was a great astronomer and keen-eyed observer.It is one thing to find something from a map or other resources, quite another to discover something in "un-tilled earth".

The telescope he used was well suited to his objectives (sorry for the bad pun) -- Lacaille's observations were mainly astrometric to make observations of the southern sky and fix the positions of the stars and make a catalogue. Lacaille wasn't a deep-sky observer except that he found quite a few objects during the course of his survey work. There were much larger 'scopes available then -- they just weren't needed for his purposes.

I think his most noteworthy discovery was M83. Given the surface-brightness and the aperture (less than 1/2 the size of the finders we use today), it was a very considerable achievement. M83 was the first deep-sky object discovered that is outside the Local Group (though he knew it not).

I just wish he hadn't (1) Cut-up Argo and (2) Devised so many tiny and inconspicuous constellations.


Off Topic: two thousand posts for Glen C before the New Year? Looks likely!


Best,

Les D

glenc
27-12-2008, 04:20 AM
Thanks Les. I liked the planetary nebula next to Trumpler 10. Has anyone seen it?
http://picasaweb.google.com.au/dunlop1826/LacailleSClustersAndNebulae#5283451 621460137106

glenc
27-12-2008, 06:10 AM
The catalogue now includes Lacaille's descriptions.
http://picasaweb.google.com.au/dunlop1826/LacailleSClustersAndNebulae#
You need to click on each image to see these.