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The LMC, in the constellation of Dorado, extends 12 moon diameters across the sky. Although large, it is not brilliant - we receive as much light from it as from a first mag star - to the naked eye it appears as a hazy patch at about 4th magnitude. Since the LMC is only 180,000 ly away, an observer armed only with binoculars can see about as much detail in it as can be glimpsed in the Andromeda galaxy, 10 times farther away, when using a 20-inch telescope.
Union Observatory Circular No. 61, p 243-261. "Catalogue of clusters and nebulae near the Large Magallanic Cloud" - R T A Innes. [Note the spelling variation]
"At Dr Hertzsprung's suggestion, I examined some photographs of the large Magallanic Cloud taken by him with the 10-inch Franklin-Adams Star Camera. The search was primarily for variable stars, but a note was taken whenever anything unusual was encountered. The area searched over
RA 4h50m to 6h 6m at Dec -62�, RA 4h 30m to 6h 15m at -74� and a little in -75�, and is very nearly covered by our star maps -64�, Nos 18 and 20 and -70� Nos 16 and 18. All objects noted were marked on their appropriate maps and the coordinates for 1875 measured thereon. The coordinates so determned are not very precise, but are within their limits exact; a few objects were off the maps and their positions are very poorly determined. A card catalogue was made, not only for the objects encountered, but also for all the nebulae and star-clusters given in Dreyer's Catalogue. The oly previous observations found in Dreyer (and elsewhere) are Sir John Herschel's Cape observations and a few made at Arequipa.
The catalogue was finally arranged in zones of declination and is so printed. The positions are all brought to 1875. The descriptions make use of the abbreviations used in Dreyers ...
Many objects were encountered twice or more and described and measured. One pair of plates (Gevaert) had long exposures and was rich. It was found that the writer's descriptions of the same object sometimes disagreed. Finally, all objects in Dreyer not originally picked up were looked for and the result stated. Where no name appears on the first column, the object has not been previously listed; the catalogue numbers are those of the CPD. The descriptions given by Herschel have been condensed by the writer; they are often lengthy and differ on different nights. Those interested sould refer to his colume of Cape Observations.
As an example, let us take the object at 5h 58.5m, -69� 12'. This appears in the CPD as "neb". It is h3006 and h considers it may be Dunlop 161, but very doubtfully so; here it was swept on twice, and was once described as a star with nebulous filmaents and once as a fine globular cluster, very condensed .Often enough, it has been impossible to decide what is seen on the photographs; take, for example, h 2989 at 5h 53.2m, -71� 12.0'; on the first opccasion it is recorded as a minute globular cluster or red star, on the second as a fine small spiral or compressed cluster. In general, when there is no description, the object seen is merely a small grey patch ,and if small enough the object might be a very red star. In some cases visual re-examintion might be useful, but such could not be undertaken this season as the Cloud transited in the daytime but the time the list was drawn up. This work may be undertaken when the 26-inch refractor is in commission.
In the list nothing distinctive in the dense parts of the Great Cloud has been omitted, but the background and texture of the Cloud vary continuously - bright and faint patches, dividing lines, groupings of stars, etc. which only a view of a negative can do justice to, diversify the whole picture. When the maps on which ever yobject recorded are looked at it is at once apparent that their distribution is uneven, their greatest density is immediately preceding the Cloud, but the girdle is broken p and Np. The centre of the Cloud and the surrounding objects are, roughly 5h 20m, -69� 20'; the looped nebula is at 5h 40m, -69� 10'. The general impression is that the region of the Cloud and its nebulae is nearly oval in shape; its longest axis of 9� is in 30-210�, its shortest of 7� in 130-310�, but the centre of density is about 1� S.E. of the centre of the oval. It is the writer's impression that the background of nebulous matter varies quickly in brightness and the dividing lines are constantly broadening or thinning and even changing their directions. The impression is so strong that it is given here, but other observers were not convinved. A slight change in the length of the exposure or the density of the image might be the cause, but one should no more predicate invariability of brightness of nebulous matter than vice versa. Variable nebulae are known, and when one considers how difficulty it is to determine variability without good comparison objects etc. the question is at least an open one."
[ The catalogue (p 244 - 261) has been photocopied and is on file, but has not been keyed into the main database files ]
Innes, UOC, p 415-423, "Nebulae, etc. in the Large Magallanic Cloud" notes:
"In Circular No 61, a catalogue of the nebulae and star-clusters seen on plates taken with the Franklin-Adams star camera is given.
The Carte du Ciel plates kindly sent from Melbourne by Dr Baldwin for proper motion purposes show an enormous number of unusual objects. Although nebulae are remarkably scarce on Carte du Ciel plates of 1-hour exposure, this is not so in the region of the Large Cloud.
The two Magallanic Clouds are in a class by themselves. Within their limits are contained, with the utmost profusion, irregular patches of nebulae, spiral nebulae, nebulous stars, nebulous clusters, loose clusters of stars, and fine globular clusters. In short, as Herschel says, 'they are to be regarded as systems sui generis which have no analogues in the northern hemisphere' (Cape Obsns, p 147)
It seemed desirable to go over this region with the 26.5-inch refractor, and to repeat under somewhat changed conditions a visual survey such as had already been made by Sir John Herschel at the Cape in the 1830s. A start was made in 1926, but a few nights' work indicated that a survey such as contemplated would take several years and would seriously interfere with the double-star program to which this observatory is committed. The work was therefore discontinued, but the results then obtained are now put on record. In most cases observations were made by both I. (Innes) and v.d.B. (van den Bos), but their results were not compared at the time, so that there is no bias.
It was also intended to go over the 1-hour Melbourne plates, but a start only was made, the results of which are given here.
In general, the Franklin-Adams plates (Circular No. 61) magnify the nebulous aspects of the objects while the Carete du Ciel plates magnify the stellar aspect, as is to be expected from the ratios of aperture to focal length.
In Harvard Annals (1916), 76, No 5, Professor Solon I Bailey, gives a provisional catalogue of Globular Clusters, remarking that even earlier catalogues were nearly complete, and that no new cluster, surely globular, has been found durinf the last half cventury . This belief is widely held, as is shown by the remarks quoted in the "Observatory" Journal for 1926, Janaury, p. 9. He adds that glboular clusters do not appear to belong to the same class as small, and apparently nebulous, clusters, containing few and comparitively bright satrs of different magnitude which abound in the large Magallanic Cloud and elsewhere, although these are in many cases described as globular clusters. In his provisional catalogue he gives, however, sixteen globular clusters situated well within the limits of the Large Cloud (4h 48m to 5h 59m, -66� to -71�)./ The examination with the 26.5-inch refractor does not bear out these conclusions. Thus, the new object at 5h 26m, -63�52', is described by both observers as a globular cluster, a miniature of Xi Tuc., whicoh puts its status beyond all doubt, as we know very well the appearance of Xi Tuc in telescopes of all apertures from 1 inch upwards. Another case is the fine globular cluster Dunlop 247+8 (5h 13m, -65� 36')k which on the best F.A. plates is quite clearly a non-nebulous cluster, and in the 26.5-inch is seen as a miniature of omega Cen. The lists give numerous other examples. Against this, several objects which look very like globular lcuters, on the F.A. plates, are not seen as such through the 26.5-inch telescope, nor appear to on the Melbourne plates.
Inh the U.O.C. No 59, p 215, the evidence, so far unshaken, was given which showed that the omega Cen. cluster was probably a near object - nearer than the stars in its neighbourhood. It is not impossible that the Magallanic Clouds may be comparatively near to us.
In H.C.O. Circ. No 271, the parallax of the Large Cloud is given as 0''.000029, which leads to sizes not easy to assimilate.
Thus, h 2986, an 11th mag. star with a nebulous envelope 20'' in diameter (or according to h, 14'') will, with the above quoted parallax, be of an enormous size. A diameter of 14.5'' would imply a real diameter of 500,000 astronomical units. This seems excessive for one star. Or again, taking the smaller size as given by J. Herschel of h 2815, a spiral nebula 100'' x 70''; the parallax ... means that in size it would take in nine or ten times the distance which separates us from alpha Cen.
Although it is granted that these figures may be correct, they certainly savour of the fantastic. The blink-microscope proper-motion lists furnish a number of stars which are certainly only seen projected on the Cloud. Their proper motions are therefore referred to it, so that if their absolute proper motions can be determined with the meridian circle, the proper motion of the Cloud itself will be ascertainable. In this way it may be possible to obtain another estimate of its distance.
Journal BAA, 36(3), December, p91.
"In these are to be found all classes of celestial objects, with the exception, apparently, of spiral nebulae. The Larger Cloud is situated according to stimates based on the contained Cepheids and Otype stars, at a distance of about 100,000 light years, and is roughtly 12,000 ly in diameter. The Smaller Cloud is thought to e at about the same distnace, or perhaps somewhat less, and approx. 600ly indiameter. ... Photos of the Larger Coud seem to show a rough spiral structure but Shapley considers it 'difficult to find any trace of genuione spiral structure on the Magellanic Clouds'. ... Sir John Herschel found that strong moonlight obliterated the Smaller Cloud to the naked eye, but not quite the Larger Cloud."
Angular dimensions of Magellanic Clouds. Harv Coll. Obs. Bulletin 796. [192?BHarO.796b....S]
Lindsay, E.M. (1964) "Some NGC objects in the Large Magellanic Cloud", IAJ, 6, 286-289
"Sir John Herschel took the LMC to lie between RA 4h 40m and 6h00m and declinations -66� and -72�. In compiling his Cataogues of objects in the Nubecula Major and Nubecular Minor, he used an 18.25-inch reflector of 20-fet focus and an equatorially mounted achromatic five-inch refractor of seven feet focus. With the refractor he measured the positions in both Nubeculae of every star visibly to the 10th magnitude, but by far the greater number of nebulae and clusters were observed with the reflector.
An interesting personal characteristic appears in Herschel's notes. He frequently referred to observations made with his left eye In his Cape Observations of Nebulae and Clusters we have for example: 2405, a difficult object but certain after long attention with the left eye; 3152 all finely resolved into perfectly equal stars like the finest dust, which are seen with the left eye without effort, but the right requires to be somewhat strained to discern them; 3690 the right eye does not resolve or barely makes it resolvable, the left eye resolves it completely into stars 17...20m. Whether or not he customarily observed with the left eye, it was certainly superior to the right in resolution and sensitivity.
The Nubecula Major Cataloge contains 919 objects of which 240 are classified as nebulae, 37 as clusters, nine as clusters or nebulae, and the rest are stars. Eighteen of these nebvulae and clusters are not in his general catalgoue of Reduced Observations of Nebulae and Clusters of Stars. Dreyer omits only three of these from the NGC, includes three from Herschel's general catalgoue which are not in the Nubecula Major list, and adds two Melbourne objects, all within the Herschel limits of the LMC. Otherwise, within the above limits of RA and Decl, all NGC objects in the LMC are taken form Herschel's Nubecula Major Catalogue.
Taking the LMC to lie between RA 3h 45m and 6h 30m and declinations -59� and -78�, there are 366 LMC objects in the NGC beginning with NGC 1466 and ending with NGC 2257. The additional objects have been taken from Herschel's general catalogue of Reduced Observations of Nebulae and Clusters of Stars. It is easy to identify most of tehse on 30-min exposure 103a-O ADH plates. A few, however, have not been found, a few have postional errors, and a few seem more likely to be ifield irregularities than clusters. A list of htese is given in the following table. As is to be expected, several objects classified as nebulae are galaxies. These are not included in the table, except those with positional errors, but are collected together at the end.
Hodge, P.W. (1975) Clusters of the Magellanic Clouds. I.A.J., 12(3/4), 77.
"Eric Lindsay's pioneering studies of the star clusters of the Magellanic Clouds produced remarkably complete and authoritative catalogues of these important objects. A review of the completeness of the searches for clusters in the LMC is included.
Exploring the Southern Sky: A pictorial atlas from the European Southern Observatory. Springer-Verlag.
Scanned image on disk. [1987EtSS.........0L], plates 1, 51, 55.
Other names: "ESO 056-115, ,A0524-69" Inclination: (face-on, in degrees) 28 Total photoelectric blue mag .91 Total colour index .51 Logarithm of the angular diameter D25 (arcminutes) 3.81 This galaxy is included in a sample of galaxies with velocity less than 500km/s with respect to the centroid of the Local Group. [Nearby Galaxies. Schmidt K.-H., Priebe A., Boller T. (Astron. Nachr. 314, 371 (1993))]
LMC: Photo index by Jim Lucyk: Sky & Tel. 1/74 p10, Sky & Tel. 1/75 p10, Sky & Tel. 3/86 p239, Sky & Tel. 4/81 p293, Sky & Tel. 4/84 p304, Sky & Tel. 7/69 p23, Sky & Tel. 12/81 p539, Sky & Tel. 7/88 p11, Astronomy mag. 7/85 p19, Astronomy mag. 9/78 p20, Astronomy mag. 12/76 p6-7, Deep Sky #4 Fa83 p10, Vehrenberg's Atlas of DS Splendors (3ed) p60, 61, Hubble Atl.of Gal. (Sandage 1961) p38
Gaposchkin, S. () "Visual brightness and form of the Magellanic Clouds", IAJ, 5, p 4-6.
"The visual brightness and form of the Magellanic Clouds have never been determined with any preciosin, as far as I know. Various photographic and photoelectric determinations exist and they show a surprisingly great variety of values. ... Their diversity illustrates the difficulty in determining the brightness of an area in comparison with a point source. Usually in such comparisons it is attempted to reduce the area to similarity with a point, as is the practice with extragalactic nebulae. Here I make use of a reverse method by transforming the point source into a small extrafocal surface.
Both Clouds lens themselves easily to comparison in this respect. To the unaided eye they apear to be more or less of uniform brihgtness over the mjaor part of their extent. Especially is this true in respect of the SMC. The LMC may be subdivided into two or thre ones of approxiamtely uniform brightness. Both clouds are surrounded by a sufficient number of bright comparison stars of well-known magnitudes.
It is interesting to note that the recently published (Eggen, O., & de Vaucouleurs, G. (1956) PASP, 68, 429) visual isophotes as determined photoelectrically do not represent well the actual impression produced by the LMC upon the unaided eye.
In a firmly mounted binocular of low power, in which the appearnace of the Cloud suffered no noticeable change as compaed with that visible to the naked eye, I matched the surface brightness of extrafocal images of stars of known magnitude wiht the surface brightness of a part of the Cloud, and plotted the size of the extrafocal images of the stars on the same graph paper with the Cloud [rest of methodology omitted].
The table below gives the numercial values for the MC as obtained by me on several evening in Novermber and December when the LMC was in its best position for visual estimates. The obserations were made on the small platform surrounding the lower part of the buildings on which the Farnham telescope, Mount Stromlo, is erected. ... The mean visual magnitude is then -1m.26. The uncertainty of the individual values can lie within 10%, or 0m.1.
... [The visual magnitude of the SMC is given as +1.23]
The accompanying sketch represents the appearance of the LMC to the unaided eye. It has been drawn several times during evenings when no atmospheric clouds were seen and the background of the sky seemed to be of a velvety dark texture, the silhouette of the Large Cloud being nearly vertical and about 50 degrees from the horizon - both confitions, as is well known, being favourable for viual sketching.
The LMC resembles visually an S-shape pattern in which the upper end is less curved than the lower. The bar, or the main trunk of the Cloud, is directed practically straight towards gamma Volantis which is the apex of the Kite constellation above Beta Carinae. The very faintly delineated shades on the periphery of our pattern around gamma Volantis may well be of spurious nature. In the projection the Milky Way is not far from the LMC; the gaseous smoke of the Galaxy rising alng a broad lane from the sun towards Carina can protrude high up and surreptitiously link the Galaxy with the Cloud. Another such visual linkage may be perceived starting from Gammma Velorum, irregularly sprawling under Canopus and joinging the Cloud about Beta and Delta Doradus; and a third begins under the Cloud and reaches the Milky Way at Corona Australis after passing the South Pole.
The LMC is definitely of a slightly brownish-grey hue, but the Small Cloud is bluish. The visual colour index of the main trunk of the Cloud would be lsightly smaller than that used above, and that of the SMC is certainly much smaller; it may be as small as 0.0m.
posted to HASTRO-L
From the research I have done, it is clear that astronomers did *not* name these galaxies nor did Pigafetta nor did Magellan himself. It would appear that various explorers/pirates first used that name before it finally became entrenched in the culture and astronomy. I am currently trying to find out who was the first and if Sir Francis Drake had something to do with the name since he followed Magellan's footsteps 60 years later. If anyone knows of a quote or a specific diary...
To complete my article, I will need the quotes from Maria Mitchell, which referred to "Magellan's Patches" and William Smyth who called them "Magellan's Coalsacks" (He also referred to the actual Coalsack Nebula as "the Black Magellanic Cloud"). I hoped I could look for the answer in Maria Mitchell's papers but Ms. Mitchell's old college never cooperated and I cannot find William Smyth's book. If anyone can help, that would be greatly appreciated.
In Andre Bordeleau's recent post, he mentioned:
[ [ I will need the quotes from Maria Mitchell, which
[ [ referred to "Magellan's Patches" and William=20
[ [ Smyth who called them "Magellan's Coalsacks"=20
[ [ (He also referred to the actual Coalsack Nebula as
[ [ "the Black Magellanic Cloud").=20
In W. H. Smyth's book, _Cycle of Celestial Objects_, vol. 1, Prolegomena (London: John W. Parker, 1844), on p. 309 he writes about the Milky Way or Via Lactea:
"It traverses the asterisms from Cassiopeia and Perseus, which it nearly covers, passing by Auriga, between Taurus and Gemini, over Orion's club, and the preceding parts of Monoceros, through Argo to the Southern Cross, keeping opposite to the Magellanic clouds, or [italics begin] Sacks of Coals, [italics end] of our early navigators."
Curator of Science & Technology Rare Books
Dibner Library of the History of Science & Technology
Special Collections Dept.
Smithsonian Institution Libraries
Washington, DC 20560-0630
ESO PR 1030: "Massive stars discovered".
ESO PR 1033: "New Tarantula image".
naked eye - IB(rs_)m IV. circ, 8 deg diam, reaching as far as epsilon/delta Dor on NE and mu/beta Men of SW; ends btwn beta & mu Men. bar in pa110, brtr at ESE end. halo has wk broad concen, then somewhat brtr at bar, which has wk even concen along its length. sev f patches (grps of cls/nebs) are vis, brtst being N2070 region. BS, 13Nov1993, LCO.
- br patch in space btwn theta Dor and delta Dor, brtst in halo N of bar, which is more extensive than to S. using UHC & [OIII] filters, the only area really consp is Tarantula Nebula region, with which neb is vbr & *ar. the band of light extending from LMC to galactic center is sl less br than zodiacal band on either side of gegenschein, nrly as wide as LMC itself. it passes south celestial pole in great circle aimed in direc of br Sgr *cloud. BS, 14Nov1993, LCO.
Date and Time: 24 January 2009, 23:25
Location: Prince Albert (Western Cape, South Africa).
Instrument: Naked eye, 10x50 binoculars (5� FOV)
Sky Conditions: Haze. Seeing: 5/10. Transparency: Poor
Naked eye: Located about 20� S from Canopus. Visible as a faint, elongated cigar shaped cloud approx 5� x 3�. Brighter central area with brightness fading gradually towards outside edges. At the western edge of the LMC 2 stars can be seen S and 1 star just to the N. With averted vision a bright round patch is visible to the NE.
10x50: Structure much more apparent. Fills the 5� FOV. The bright central bar shows patches of faint nebulosity inside and in surrounding area. The Tarantula Nebula is clearly visible as a bright round patch to the NE. Individual stars of varied brightness visible within the diffuse glow.
LMC is three fingers wide, and the SMC is 2 fingers across.
Location: Bonnievale SSP
Equipment: Canon 12x36 binocs, 5-deg fov
Sky conditions: Excellent 9/10
Quality of observation: Good
LMC is an irregular galaxy, largest visible from Earth; impressive nebulosity. m = 0.5. Core size 250 x 50-arcmin (650 x 170-arcmin total). Tarantula Nebula and another nebula east of it (NGC 1966).
The Messier objects
The Bennett objects
The Caldwell list
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