The First Southern Catalogue

[glenc]

Lacaille made the first catalogue of southern star clusters and nebulae.

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 (M83). 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 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 Dunlop made the next search for southern clusters and nebulae.

Here are some historical images
https://picasaweb.google.com/110048826379679252146/Lacaille

and a biography
http://messier.seds.org/xtra/Bios/lacaille.html

[glenc]

Lacaille's Catalogue provides a good list of objects for beginners to observe.
http://messier.seds.org/xtra/history/lacaille.html

It includes 7 globular clusters NGC 104 (47 Tuc), NGC 4833, NGC 5139 (omega Cen), M 4, M22, M55 and NGC 6397.
There are also 3 nebulae NGC 2070 (Tarantula), NGC 3372 (he divided eta Car into 2 parts) and M8 (Lagoon).
He missed the bright globular cluster NGC 6752 and the open cluster NGC 6067.

The attached pdf file gives his objects in RA (Right Ascension) order.

[dj gravelrash]

Excellent work Glen. Thanx muchly, all us newbies appreciate your posts --cheers m8

[glenc]

Lacaille, James Dunlop and John Herschel made the first three catalogues of southern clusters and nebulae. The attached Google map shows the location of Lacaille's and Herschel's telescopes at Cape Town. It also shows the government observatory and the top of the Table Mtn cable car.

Lacaille used a 0.5" refractor in 1751-52.
Dunlop used a 9" reflector in 1826 at Parramatta, Sydney.
Herschel used an 18.5" reflector from 1834-38.

Here is a list of all the NGC and IC observers.
http://www.klima-luft.de/steinicke/ngcic/obs_e.htm

[mikerr]

Thanks for posting Glen. Much appreciated. :thumbsup:

Michael.

[glenc]

Lacaille's Observatory was at http://binged.it/RlfRTU

The photo shows old houses on Strand Street between today’s Adderley St. and St. Georges Mall. La Caille lived and worked in the house on the right.
http://www.geocaching.com/seek/cache_details.aspx?guid=0b21391b-59ca-40bb-a151-f78886de6401

[glenc]

Lacaille's catalogue of 9766 stars
https://play.google.com/books/reader?id=hbEvAQAAMAAJ&printsec=frontcover&output=reader&authuser=0&hl=en&pg=GBS.PR1
https://play.google.com/books/reader?id=hbEvAQAAMAAJ&printsec=frontcover&output=reader&authuser=0&hl=en&pg=GBS.PA1

Dates observed
https://play.google.com/books/reader?id=hbEvAQAAMAAJ&printsec=frontcover&output=reader&authuser=0&hl=en&pg=GBS.PA297

Lacaille's 42 clusters and nebulae
http://messier.seds.org/xtra/history/lacaille.html

[glenc]

Nicolas-Louis de la Caille Astronomer and Geodesist
by I.S. Glass Oxford University Press (http://ukcatalogue.oup.com/product/9780199668403.do#.UIWQ9uUam8A), Published December 2012, ISBN 978-0-19-966840-3

This is the first comprehensive biography of one of the greatest and most careful observational astronomers of all time, Nicolas-Louis de La Caille (1713-1762). Trained at the Paris Observatory under Cassini II, La Caille became Professor of Mathematics at the Mazarin College and built an observatory on its roof. Here La Caille began his lifelong programme of finding accurate postions for the bright stars, against which he could measure the paths of the Sun and planets.
During his expedition to the Cape of Good Hope in the years 1751-53 he mapped the southern sky and gave many of the constellations the names by which they are still known. In conjunction with simultaneous measurements from Europe, he determined the distances of the planets Venus and Mars.
In addition, while at the Cape, he contributed to geodesy by measuring the radius of the earth and paradoxically came to the conclusion that it is pear-shaped. The explanation of his error lay with local gravitational anomalies caused by mountains that deflected his plumb lines.
La Caille interested himself in navigation and developed a practical procedure for making use of the Moon to determine longitudes at sea, known as the method of Lunars.
He fed precise data to the leading applied mathematicians of the time, D'Alembert, Maupertuis and Clairaut. This information was critical to the development of the theory of planetary perturbations. La Caille was a firm believer in Newton's theory of universal gravitation, for which he was an able propagandist.
Apart from his astronomical and geodetic work, while at the Cape La Caille made extensive notes of conditions among the colonists and slaves. His remarks constitute perhaps the most reliable commentary on conditions at the time.
http://www.saao.ac.za/~isg/lacaille.html
http://ukcatalogue.oup.com/product/9780199668403.do#.Ua-l5ZyBaoR

[Max Vondel]

Thanks Glen for the excellent history of la Caille
WOW 0.5" refractor....
Imagine what he could have done with a 7x50 finderscope!
:rofl: