Nicholas Louis de Lacaille

[glenc (Glen)]

Nicholas Louis de Lacaille (March 15, 1713 - March 21, 1762)
was the first to make a catalogue of southern deep sky objects.
You can read about him here.
http://www.seds.org/messier/xtra/Bios/lacaille.html

His catalogue is here:
Lacaille's Catalog of Nebulae of the Southern Sky
http://www.seds.org/messier/xtra/history/lacaille.html
He observed from Cape Town with a 0.5" refractor.

I visited France this year and took some pictures. You can see them here:
http://picasaweb.google.com/dunlop1826/Lacaille

[h0ughy (David)]

great info and pics, thanks for posting them

[glenc (Glen)]

Liked your moon pic in AS&T too.

[h0ughy (David)]

Originally Posted by glenc

Liked your moon pic in AS&T too.

Thanks Glen

[glenc (Glen)]

Here are some objects from Lacaille's Catalogue.
He made his catalogue of 42 objects in 1751-52 at Cape Town using a 0.5" refractor.
It was the first southern deep-sky catalogue. and was finished 6 years before Messier found M1 on September 12, 1758.

NGC Type Const Other
2070 BN Dor 30 Dor
3372 BN Car Eta Car
6523 BN Sgr M8
104 GC Tuc 47 Tuc
4833 GC Mus
5139 GC Cen Omega Cen. Halley found this first.
6121 GC Sco M4
6397 GC Ara
6656 GC Sgr M22
6809 GC Sgr M55
5236 GX Hya M83 an amazing find!
2477 OC Pup
2516 OC Car
2546 OC Pup
2547 OC Vel
3228 OC Vel
3293 OC Car
3532 OC Car
3766 OC Cen
4755 OC Cru K Cru
5281 OC Cen
5662 OC Cen
6025 OC TrA
6124 OC Sco
6231 OC Sco
6242 OC Sco
6405 OC Sco M6
6475 OC Sco M7
IC2391 OC Vel o Vel
IC2488 OC Vel
IC2602 OC Car

[CoombellKid]

A half inch refractor, boy I wonder how they got around aperture fever back
then. To think most folks today wouldn't even use that as a finderscope. But
then again I would imagine he would of been pretty happy with just a GSO
9 x 50 finderscope.

[xelasnave]

He was able to get so much done becuase he did not take long to set up .. yes indeed half inch I wonder what he would have thought of some 80mm binos Thanks for sharing Glen
alex

[glenc (Glen)]

Who Discovered M69?

It seems that Messier was the first to see it, but he didn’t know it.
Messier thought that Lacaille discovered M69.

On August 31, 1780 Charles Messier described M69 as a:
`Nebula without star, in Sagittarius, below his left arm & near the arc; near it is a star of 9th magnitude; its light is very faint, one can only see it under good weather, & the least light employed to illuminate the micrometer wires makes it disappear: its position has been determined from Epsilon Sagittarii: this nebula has been observed by M. de La Caille, & reported in his Catalogue; it resembles the nucleus of a small Comet.' (diameter 2')

Messier thought that M69 was the same as Lacaille I.11 but this is unlikely for four reasons.
1. There is an obvious asterism at the position given for Lac 1.11 and it similar to other asterisms in Lacaille’s catalogue. (Lac I.13, III.9 and III.14.)
2. Lacaille’s positions are usually fairly accurate but M69 is 1.18d (or 70’) from L I.11 in pa 14d, and Lacaille does not make large errors like that. The largest error he made was 10 mins of time or 43 arc mins in RA with 47 Tuc, and that seems to be a typographical error. It is most unlikely that he would make a large error in both declination and RA at the same time.
3. M69 is too faint for Lacaille at magnitude 7.6. The faintest globular in his catalogue, apart from M69, is magnitude 6.9. He missed nine GCs brighter than magnitude 6.8, so it is unlikely he would include one that is magnitude 7.6.
4. M69 and L I.11 have different NGC numbers (NGC 6637 and 6634) because John Herschel listed them separately.

(This is a repeat of a previous post)

[glenc (Glen)]

In order to fill the star poor regions between the Bayer Group and the other constellation families the astronomer LaCaille conceived the following 13 constellations. He broke with tradition and gave them scientific names (with one exception: Mensa):

Norma, the Level.
Circinus, the Compasses
Telescopium, the Telescope.
Miscroscope, the Microscope.
Sculptor, the Sculptor's Apparatus.
Fornax, the Furnace.
Caelum, the Graving Tool.
Horologium, the Clock.
Octans, the Octant.
Mensa, the Table Mountain (Table Mountain at Capetown)
Reticulum, the Net.
Pictor, the Easel.
Antlia, the Air Pump.

http://www.seds.org/Maps/Const/const_family.html

[Ric]

Great bio and info Glen, it is always fascinating to read about the pioneers of Astronomy, no doubt they had wonderfully dark skies in those days.

Thanks

[glenc (Glen)]

Yes it would be hard to discover DSO from Cape Town today (LaCaille & Herschel) or from Parramatta (Dunlop).

[Ric]

I also find it totally amazing that it was all done with a 0.5" refractor.
That is dedication.

Cheers