Some Dunlop Objects

[glenc]

I thought I would combine some James Dunlop descriptions with images from IIS people.
James Dunlop observed from his back yard in Parramatta, Sydney with a homemade 9" aperture f/12 speculum reflector in 1826.
He was a typical Aussie battler, a poor man with little education. I think he did a great job.

Here is the first Dunlop object.
He found the galaxy Dunlop 482 = NGC 5128 = Cen A and wrote; "A very singular double nebula, about 2.5' long, and 1' broad, a little unequal: there is a pretty bright small star in the south extremity, of the southernmost of the two, resembling a bright nucleus: the northern and rather smaller nebula is faint in the middle, and has the appearance of a condensation of the nebulous matter near each extremity: These two nebula are completely distinct from each other, and no connection of the nebulous matters between them. There is a very minute star in the dark space between the preceding extremities of the nebula: they are extended in the parallel of the equator nearly."

This image is by Fred Vanderhaven aka Bassnut.
http://fredsastro.googlepages.com/NGC5128finalwebB.jpg/NGC5128finalwebB-full;init:.jpg

[glenc]

Dunlop described the nebula Dunlop 322 = NGC 3324 (near eta Car) as;
"A star of the 7th magnitude, involved in faint nebula."

Here is another image by Bassnut.
http://fredsastro.googlepages.com/G15-ngc3324-NBsml.jpg/G15-ngc3324-NBsml-full.jpg

[Ric]

Great descriptions combined with some lovely images.

Very nice Glen.

[glenc]

So far I have included one galaxy and one nebula, it is time for a planetary nebula.
Here is the picture by Frank aka Spearo.
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=16113&d=1156406166
and this is Dunlop's description.
D252 = NGC 5189 "A very faint nebula, about 25" diameter. It is very near a star of the 8th magnitude, and near the north following extremity of a crescent of very small stars."
The crescent of stars is in the lower left part of Frank's image.

[glenc]

Dunlop described the GC D265 = NGC 2808 as "A very bright round nebula, about 3’ or 4' diameter, very gradually bright to the centre. This has a fine globular appearance"
This image is by Terry B.
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=37337&d=1200918388

[glenc]

Bill Christie took this image of D360 = NGC 6067.
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=13020&d=1149005438
Dunlop described this OC as "A pretty large cluster of small stars of mixed magnitudes, about 12’ diameter; the stars are considerably congregated towards the centre, extended south preceding and north following."

There is an interesting PN Menzel 2 = PK 329.3-02.8 near the above OC. It is mag 12.5 and 27" across.
To find it go 25' south from the OC to the orange mag 5 star kappa Nor then continue 21' in almost the same direction.

[glenc]

"DUNLOP, JAMES (1793-1848), astronomer, was born on 31 October 1793 at Dalry, Ayrshire, Scotland, the son of John Dunlop, weaver, and his wife Janet, née Boyle. After primary level his education was at night-school in Beith where he worked in a thread factory. He was constructing telescopes at 17, and some ten years later an acquaintance with Sir Thomas Brisbane (http://www.adb.online.anu.edu.au/biogs/A010141b.htm) developed his interest in astronomy. When appointed governor of New South Wales, Brisbane resolved to establish an observatory, and chose Dunlop and Carl Rümker (http://www.adb.online.anu.edu.au/biogs/A020359b.htm) as assistants. They arrived in Sydney on 7 November 1821 and the instruments were set up in Parramatta in time to observe the solstice. A building was erected and regular observations began in May 1822. Apart from making the greater part of the observations for a catalogue of stars, Dunlop made observations of the length of the pendulum, the results of which were published with those of Captain Henry Kater in Philosophical Transactions of the Royal Society, 1823. In June 1822 Dunlop was the first to see the reappearance of Encke's comet. This was only the second case of the predicted return of a comet being verified, the first being that of Halley in 1758.
From June 1823, when Rümker left the observatory, to February 1827 was a busy period for Dunlop: he made about 40,000 observations which form the basis of the Parramatta Catalogue of Stars and, with an instrument built by himself, made the observations for his catalogues of nebulae and star clusters, and double stars. He then returned to Scotland to work in Brisbane's private observatory at Makerstoun in Roxburgh.
In 1831 Dunlop was appointed superintendent of Parramatta Observatory, which had been taken over by the government. He found the equipment and buildings of the observatory in bad condition, and had to exert much effort to restore them. In the period to 1835 he reported observations of asteroids, planets and comets in Memoirs of the Royal Astronomical Society. He made many transit observations, particularly with the new transit circle by Jones which he installed in 1835. He gave help and advice to Major (Sir) Thomas Mitchell (http://www.adb.online.anu.edu.au/biogs/A020206b.htm) when he was preparing his expeditions in 1831 and 1834. However, from about 1837 Dunlop appears to have been in ill health, his activity declined and the transit work done from 1832 at Parramatta was never reduced or published. He resigned and retired to his farm on Brisbane Water in August 1847 and died on 22 September 1848. His wife, Jean Service, whom he married in 1816, survived him for eleven years. They had no children..."
http://www.adb.online.anu.edu.au/biogs/A010322b.htm

See also: http://www.austehc.unimelb.edu.au/fam/1527.html
and: http://nla.gov.au/anbd.bib-an10670779

[glenc]

Dunlop found the 5 objects below and he also was the first to see the galaxy D411 = NGC 4945. Here is an image from Garyh http://www.iceinspace.com.au/forum/attachment.php?attachmentid=40920&d=1207540295 of the object Dunlop described as:
"A beautiful long nebula, about 10' long, and 2' broad, forming an angle with the meridian, about 30° south preceding and north following; the brightest and broadest part is rather nearer the south preceding extremity than the centre, and it gradually diminishes in breadth and brightness towards the extremities, but the breadth is much better defined than the length. A small star near the north, and a smaller star near the south extremity, but neither of them is involved in the nebula. I have strong suspicions that this nebula is resolvable into stars, with very slight compression towards the centre. I have no doubt but it is resolvable. I can see the stars, they are merely points. This is north following the 1st xi Centauri."
It is resolvable but I don't think Dunlop resolved it! The mag 11 galaxy NGC 4976 is 30' following.

[glenc]

In 1826 Dunlop described D564 = NGC 2818 as "A pretty large faint nebula of a round figure, 6' or 8' diameter; the nebulosity is faintly diffused to a considerable extent. There is a small nebula in the north preceding side, which is probably a condensation of the faint diffused nebulous matter; the large nebula is resolvable into stars with nebula remaining."
Terry B took this image: http://www.iceinspace.com.au/forum/attachment.php?attachmentid=37823&d=1201867222

[glenc]

Paul Mayo (PhotonCollector) took this image of D 332 = NGC 3199.
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=12621&d=1148114670

James Dunlop wrote "A very faint ray of nebula, about 2' broad, and 6' or 7' long, joining two small stars at the south following extremity, which are very slightly involved, but their lustre is not diminished from that of similar small stars in the field. The north extremity also joins a group of small stars, but they are not involved. Figure 15."
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=42583&d=1210454078
Note Dunlop’s position is exactly 1 degree north of N3199, a copy error. The description and figure match N3199. The figure has south at the top.

[glenc]

The globular D445 = NGC 3201 has a low concentration.
Clive (Alchemy) took this image: http://www.iceinspace.com.au/forum/attachment.php?attachmentid=39261&d=1204275793

Dunlop's description was "A pretty large pretty bright round nebula, 4' or 5' diameter, very gradually condensed towards the centre, easily resolved into stars; the figure is rather irregular, and the stars are considerably scattered on the south preceding side: the stars are also of slightly mixed magnitudes."

The PN NGC 3132 is 6.3 degrees north (pa 163). Brian Warner notes that Dunlop recorded this as “Dusky Yellow – a fine Planetary disc” in his star catalog but did not included it in his Catalogue of Nebulae and Clusters of Stars in the Southern Hemisphere observed in New South Wales.
http://seds.lpl.arizona.edu/messier/Xtra/similar/dunlop.html

[glenc]

Mike (Iceman) took this image of the OC D297 = NGC 3114: http://www.iceinspace.com.au/forum/attachment.php?attachmentid=39797&d=1205264951

It is "A beautiful cluster of stars, arranged in curvilinear lines intersecting each other, about 40' diameter, extended south preceding, and north following." according to its discoverer, James Dunlop.

This naked eye cluster was, surprisingly, not included in Nicolas Lacaille's 1752 catalog.
http://seds.org/MESSIER/xtra/history/lacaille.html

The Dunlop catalog is sorted from south to north in declination order, not by RA like most modern catalogs.
D1 is the most southerly object and D629 the most northerly.

[glenc]

“If men like [John] Herschel are to spend the best years of their lives in recording for the benefit of a remote posterity the actual state of the heavens…what a galling discovery to find amongst their own contemporaries men [James Dunlop] who … from carelessness and culpable apathy hand down to posterity a mass of errors …[so] that four hundred objects out of six hundred could not be identified in any manner … with a telescope seven times more powerful than that stated to have been used!”[1]

[1] James David Forbes, ‘Results Results of Astronomical Observations made during the years 1834, 5, 6, 7, 8 at the Cape of Good Hope, being a completion of a telescopic survey of the whole surface of the visible heavens commenced in 1825’, The Quarterly Review, 85, 1849, pp 1-31.

[glenc]

John Herschel wrote:
“Of the objects remaining, 135 are nebulae and clusters of my Father's catalogues, now, for the first time, re-observed; 9 are Messier's, 5 of which are identical with objects catalogued by Mr. Dunlop; and 206 others have also been identified, with more or less certainty (indicated by the absence or presence of the sign ?), with objects observed by Mr. Dunlop, and described in his Catalogue of Nebulae. The rest[1] of the 629 objects, comprised in that catalogue, have escaped my observation; and as I am not conscious of any such negligence in the act of sweeping as could give rise to so large a defalcation, but, on the contrary, by entering them on my working lists (at least, until the general inutility of doing so, and loss of valuable time in fruitless search, thereby caused it to become apparent), took the usual precautions to ensure their rediscovery; and as I am, moreover, of [the] opinion that my examination of the southern circumpolar region will be found, on the whole, to have been an effective one, I cannot help concluding that, at least in the majority of those cases, a want of sufficient light or defining power in the instrument[2] used by Mr. Dunlop, has been the cause of his setting down objects as nebulae where none really exist. That this is the case, in many instances, I have convinced myself by careful and persevering search over and around the places indicated in his catalogue.”[3]

[1] 418 objects = 66.5%
[2] The original footnote says, “A 9-inch Newtonian reflector, of 9 feet focal length, which, in point of light, would correspond to about one-seventh of that used in my [John Herschel] sweeps. That such was its construction, I conclude from the mention of the large mirror in Philosophical Transactions, 1828, p.113.”
[3] J. Herschel, Astronomical Observations, p. 3.

[glenc]

Greg (gregbradley) created this image of D262 = NGC6744: http://www.pbase.com/image/96539963

In 1826 Dunlop discovered "A pretty large very faint nebula, about 5’ or 6’ diameter, slightly bright towards the centre; a minute star is north of the nebula, and two stars of the 7th magnitude preceding."

This galaxy is visible in 20x80 binoculars and has a low surface brightness.

[glenc]

Nicolas Lacaille missed this bright globular and Dunlop saw it as "A pretty large and very bright nebula, 5’ or 6’ diameter, irregular round figure, easily resolved into a cluster of small stars, exceedingly compressed at the centre. The bright part at the centre is occasioned by a group of stars of some considerable magnitude when compared with those of the nebula. I am inclined to think that this may be two clusters in the same line; the bright part is a little south of the centre of the large nebula."

This image of D295 = NGC6752 was taken by Michael Samerski (smersh):
http://www.metronome-trading.com/me/ngc_6752.htm

NGC 6752 is only 3.8 degrees north of NGC 6744.
Both are visible in Roger Groom's (rogerg) image:
http://content.rogergroom.com/cms/000775.jpg

[glenc]

D25 = NGC346 is the brightest nebula in the SMC. It lies between the GC NGC330 and the OC NGC371.

Eric Lo (EzyStyles) took this image of 330 (top right) and 346.
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=32646&d=1191567520

Jason Jennings (jase) took this image of the SMC http://cosmicphotos.com/gallery/image.php?fld_image_id=126&fld_album_id=12.

Dunlop described D25 as "A pretty large pretty bright nebula, about 2.25 ' diameter, irregular round figure, resolvable, very slight condensation, not well defined at the edges."

His 9" aperture speculum reflector telescope had a limiting magnitude of 13 and was equivalent to a modern 6.5" Newtonian.

[glenc]

This is D606 "A faint nebula, about 1.25' long and 30" or 40" broad, with a considerable brightness near each end, and faint in the middle, resembling two small nebulae joined." according to Dunlop.
I am not certain that Dunlop saw this and your comments are welcome.

Tony (Striker) took this image: http://www.iceinspace.com.au/forum/attachment.php?attachmentid=16852&d=1158142906

[glenc]

D413 is "A cluster of small stars, with a bright star in the preceding side. A very considerable branch or tail proceeds from the north side, which joins a very large cluster."

This OC in is the nebulae NGC 6188 which was imaged by Paul Mayo (PhotonCollector) http://www.iceinspace.com.au/forum/attachment.php?attachmentid=32354&d=1190883235
The cluster is on the right in the image. The nebulae was found by John Herschel, it is an easy object in a 12" scope with a UHC filter.

[glenc]

Steven Juchnowski (sjastro) posted this image of D 507 = NGC 55
http://users.westconnect.com.au/~sjastro/ngc55c.html (http://users.westconnect.com.au/%7Esjastro/ngc55c.html)
NGC 55 is visible in a 50mm finder.

Dunlop discovered "A beautiful long nebula, about 25' in length; position north preceding, and south following, a little brighter
towards the middle, but extremely faint and diluted to the extremities. I see several minute points or stars in it, as it were through the nebula: the nebulous matter of the south extremity is extremely rare, and of a delicate bluish hue. This is a beautiful object."
He saw it 182 years ago on Fri 7/7/1826 at 5:05am with his 9" reflector. He also discovered NGCs 134, 7552 and 7582 that night.
Imagine discovering 4 galaxies in one night!

[hector]

Some time ago I created a Web page on the SMC and in it's history section I had the following information on James Dunlop
"James Dunlop of the Parramatta Observatory was one of the first people to observe the SMC with a telescope. In 1820 he became the assistant at the new observatory and was promoted to the superintendent from 1831 to 1847. During this time he catalogued over 7835 stars and in 1826 he published a list of 621 nebulae and a catalogue of nebulae and clusters of stars in the Southern Hemisphere observed at Parramatta in New South Wales.
The Nebula Minor, to the naked eye, has very much the appearance of a small Cirrus-cloud; and through the telescope, it has very much the appearance of one of the brighter portions of the Milky Way although it is not so rich in stars of all the variety of small magnitudes, with which the brighter parts of the Milky Way in general abound, and therefore it is probably a beautiful specimen of the nebulosity of which the remote portion of that magnificent zone is composed"

[glenc]

James Dunlop came to Australia with Gov T Brisbane and C Rumker in November 1821 and worked on a catalogue of 7385 star from May 1822 until March 1826. From April to November 1826 he made a catalogue of 629 nebulae and clusters and also a catalogue of 253 double stars from his back yard. He observed the SMC on 6 nights between 1/8/1826 and 6/9/1826. He returned to Scotland in 1827 and published his catalogues in 1827 and 1828, then came back to Sydney in November 1831.

[glenc]

Dunlop 281 = IC 2714 is "A cluster of very small stars, a little elongated preceding and following, about 10' diameter; the stars are congregated towards the centre, a pretty bright star south, and a double star south following this" according to Dunlop.
He discovered this cluster on 27/4/1826, the night he started making his catalogue of 629 nebulae and clusters. He also discovered Mel 105 that night and re-observed the Lacaille clusters NGC 3532 and NGC 3766 as well.
John Herschel missed both IC 2714 and Mel 105.

Three of these clusters are in this image by John Drummond.
http://www.possumobservatory.co.nz/lambda_cen-neb-300mm_mamiya_lens@f5,6-10min-lum1x1,rgb3x3-20c-080428-web-ip.jpg
Drummond says "IC 2948 was discovered by Royal Harvard Frost in 1906-8.
The open cluster at the upper right is NGC 3766 (the Pearl Cluster). The strip of four bright stars in the centre of this object is open cluster IC 2944. The round nebula at centre right is RCW 60 and the small nebula at centre bottom is RCW 61. Open cluster 2714 is at lower right and smaller Melotte 105 is lower yet. This object is also known as the "Running Chicken Nebula."

[glenc]

D 67 = NGC 4372 has the longest description in Dunlop's catalogue: "A star of the 6th magnitude, with a beautiful well-defined milky ray proceeding from it south following; the ray is conical, and the star appears in the point of the cone, and the broad or south following extremity is circular, or rounded off. The ray is about 7' in length, and nearly 2' in breadth at the broadest part, near the southern extremity. With the sweeping power this appears like a star with a very faint milky ray south following, the ray gradually spreading in breadth from the star, and rounded off at the broader end. But with a higher power it is not a star with a ray, but a very faint nebula, and the star is not involved or connected with it: I should call it a very faint, nebula of a long oval shape, the smaller end towards the star; this is easily resolvable into extremely minute points or stars, but I cannot discover the slightest indications of attraction or condensation towards any part of it. I certainly had not the least suspicion of this object being resolvable when I discovered it with the sweeping power, nor even when I examined it a second time; it is a beautiful object, of a uniform faint light."
Dunlop catalogued 9 objects on 30/4/1826 including this one.

This image is from Barb and David (Tamtarn) http://www.iceinspace.com.au/forum/attachment.php?attachmentid=39352&d=1204439461

[glenc]

The star eta Car was near its maximum when Dunlop wrote "(eta Roboris Caroli, Bode) is a bright star of the 3rd magnitude, surrounded by a multitude of small stars, and pretty strong nebulosity; very similar in its nature to that in Orion, but not so bright. Figure 14 is a very correct representation of it; the circle A B is about 1° and 37' diameter, with the star eta in the centre. I can count twelve or fourteen extremely minute stars surrounding eta in the space of about 1'; several of them appear close to the disk: there is a pretty bright small star about the 10th magnitude north following eta, and distant about 1'. The nebulosity is pretty strongly marked; that on the south side is very unequal in brightness, and the different portions of the nebulosity are completely detached, as represented in the figure. There is much nebulosity in this place, and very much extensive nebulosity throughout the Robur Caroli, which is also very rich in small stars."

Adam (Buddman) recorded this image of the nebulae D309 = NGC 3372.
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=41175&d=1207923271
In 1752 Nicolas Lacaille divided this nebulae into two parts Lac III 5 and III 6.

John Herschel records the star eta Car 1837-38 outburst:
http://books.google.com.au/books?id=lHVY4HxTlpcC&pg=PA99&lpg=PA99&dq=eta+Carina++Herschel&source=web&ots=UwE5I-cT35&sig=H8OPeZ6MmGYzODt_2uja8OPfwGY&hl=en&sa=X&oi=book_result&resnum=9&ct=result
The Shadow of the Telescope By Gunther Buttmann page 99

[glenc]

Dunlop 559 is "A singular dark space in the heavens, of an irregular figure, about 1.5 deg long, and 1.5 deg broad; no stars except exceedingly minute stars in the greatest portion of this space. There is a bright star in each side."
It was recently given the name Bernes 157.

Jase made this impressive image of the CrA area.
http://www.cosmicphotos.com/gallery/image.php?fld_image_id=106&fld_album_id=11

[glenc]

Clive (Alchemy) took this image of D 608 = NGC 7793.
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=33242&d=1192531981

On 4 Aug 1826 Dunlop discovered "A faint round nebula, about 2' diameter, with very slight condensation towards the centre; a double star is north preceding." John Herschel missed this bright galaxy. The NGC wrongly credits its discovery to George P Bond (from Harvard) who saw it using a 4” refractor on 7 Nov 1850.

There was a SN in 7793 recently but it is no longer visible in my 12" Dob.

[glenc]

Halley discovered this magnificent globular in 1677 when he was at St Helena Island. Lacaille also observed it from Capetown in 1751. Dunlop wrote " Omega Centauri (Bode) is a beautiful large bright round nebula, about 10' or 12' diameter; easily resolvable to the very centre; it is a beautiful globe of stars very gradually and moderately compressed to the centre; the stars are rather scattered preceding and following, and the greatest condensation is rather north of the centre: the stars are of slightly mixed magnitudes, of a white colour. This is the largest bright nebula in the southern hemisphere."

Matt (Matty P) took this image of D 440 = NGC 5139 http://www.iceinspace.com.au/forum/attachment.php?attachmentid=45430&d=1216812499

Notice the two dark eyes in the middle of this cluster.

[glenc]

D 142 = NGC 2070 = the Tarantula nebula is the brightest nebula in Bert's (avandonk) magnificent image of the LMC.
http://members.optusnet.com.au/~fmlee/lmcmos_hdr.jpg (http://members.optusnet.com.au/%7Efmlee/lmcmos_hdr.jpg)

Dunlop wrote "(30 Doradus, Bode) is a pretty large, ill-defined nebula, of an irregular branched figure, with a pretty bright small star in the south side of the centre, which gives it the appearance of a nucleus. This is resolvable into very minute stars. Figure 4, is a very good representation of the nebula resolved. (N.B. The 30 Doradus is surrounded by a number of nebulae of considerable magnitudes, 9 or 10 in number, with the 30 Doradus in the centre..)
The nebula was discovered by Lacaille.

Dunlop catalogued the LMC on 7 nights between 3 Aug 1826 and 6 Nov 1826.
He swept back and forth across it 5 times, in north-south sweeps, and drifted across it 6 times.

[glenc]

D 285 = Mel 101 is located on the top right edge of IC 2602 in this image by Humayun (Octane).
http://members.optusnet.com.au/mrozycka/Magellan_Observatory/Magellan_Observatory_20070121_South ern_Pleiades.html

Dunlop discovered "A cluster of extremely small stars, resembling a faint nebula, about 6' diameter; round figure."
John Herschel failed to include both Lacaille's IC 2602 and Dunlop's Mel 101 in his catalogue.

[glenc]

Did Dunlop see NGC 6326?
John Herschel thought not. He wrote regarding NGC 6326 = h3675, (N.B. -- Referring to the description of Dunlop 381, I see no ground to suppose that this can by possibility have been the object intended by that place and description ['an extremely faint small nebula, about 12 arcseconds diameter, with a bright point in the centre']. At all events, the remarkable planetary character has escaped notice by the author of that description) sweeps 599 on 19/6/1835 and 789 on 6/6/1837.

Dunlop's position was out by 27.5' in pa 91 which is not unusual for him. The PN is magnitude 11 and Dunlop's limiting magnitude is 13 so he may have seen it, although its small 18" size makes it debatable.

Here are two images http://www.ngcic.org/dss/n/6/n6326.jpg and http://www.ucalgary.ca/~zhangc/pnimage.html
There are no IIS images of this PN.

[glenc]

This image was taken by Daniel Verschatse of Chile.
http://www.astrosurf.com/antilhue/ngc1316.htm
I haven't seen any images of these two galaxies on IIS.

Dunlop 548 (N1316) is "A rather bright round nebula, about 1.5' diameter, gradually condensed to the centre" and Dunlop 547 (N1317) is "A small faint round nebula, about 15" diameter" according to Dunlop.
NGC 1316 is an easy object in a 50mm finder. John Herschel did not include NGC 1317 in his catalogue.

NGC 1317 was discovered on the last night that Dunlop catalogued new objects, 24/11/1826. He also found NGC 1350 that night.
James Dunlop started his catalogue of 629 objects on 27/4/1826 and finished it less than 7 months later.

Charles Messier took much longer to make his catalogue, he started on 21/8/1758 and finished more than 22 years later on 24/3/1781.
http://www.maa.clell.de/Messier/E/Xtra/History/dis-tab.html
Messier used an 8" and Dunlop a 9" reflector.

[glenc]

Historical:
http://picasaweb.google.com/dunlop1826/DunlopRumker

Some Dunlop globular clusters:
http://picasaweb.google.com/dunlop1826/DunlopGlobularClusters

Some Dunlop galaxies:
http://picasaweb.google.com/dunlop1826/DunlopGalaxies

[glenc]

It is 160 years next Tue since James Dunlop died.
Late in August 1848 Dunlop and a friend strayed from the track and were lost, while walking home from Gosford one night. The winter night in the bush and “the cold and exposure told severely on Mr Dunlop's already shattered constitution.” He died on September 23, 1848 of Urinary Calculus (Kidney Stones) aged 54. He is buried at St Paul's Anglican Church, Kincumber, with his wife Jane, who died 11 years later

[GrahamL]

Have you observed all 629 glen ?

[glenc]

No, I have identified about 380 objects and seen most of them.
John Herschel only found 211 Dunlop objects so I have increased that number by 80%.

Dunlop included many faint mag 11 double stars in his catalogue because his resolution was poor.
Most times it is hard to know which double star he saw because his positions were often out by 10' or 20'.

It is interesting that Dunlop died on the equinox, on 23/9/1848 it was at 8:20am AEST.

[glenc]

Today's APOD shows the Dunlop galaxy D600 = NGC 1532. The image was made by Robert Gendler.
http://antwrp.gsfc.nasa.gov/apod/image/0811/NGC1532_gendler.jpg
Dunlop described it as " An extremely faint ill-defined nebula, rather elongated in the direction of the meridian, gradually a little brighter towards the centre." He discovered four galaxies on 29/10/1826, NGCs 1487, 1512, 1532 and 2090. Not a bad effort for one night with a 9" speculum mirror. http://astroprofspage.com/archives/1229

[CoombellKid]

I have the initial list of 110 (from memory) that you posted to SEDS in my AN : ) would like the 380 list : )))

[glenc]

The open cluster Dunlop 358 = Trumpler 23 (top left in attached image) is "A pretty large faint nebula, of an irregular figure, about 6' diameter, very faint" according to Dunlop. The nebulae Gum 50 = RCW 99 (lower right) is 17' from it.
Dunlop catalogued 3 objects on 1/7/1826, the OC Tr23, the PN NGC 5189 and the OC Lac I.7 = NGC 5281.
The image is from http://www.wikisky.org/ See also http://galaxymap.org/cgi-bin/rcw.py?s=91
Trumpler named the OC Tr23 104 years later in 1930.

[glenc]

I have been using wikisky.org to make images of the 425 Dunlop objects outside the LMC and SMC.
Dunlop 255 was interesting. The attched 56' x 56' image is centered on Dunlop's exact position.
Dunlop described D255 = IC5250 as "A small faint elliptical nebula in the parallel of the equator, about 25" long, and 12" or 15" broad."
The long thin galaxy above D255 is IC5249 and NGC7358 is to the right of D255.
John Herschel missed the five IC galaxies in this image.

[ngcles]

Hi Glen & All,

That is a very nice image of IC 5249 in particular.

I can remember observing this field about 4 years ago with the 18" at Mudgee and I was sure I'd made notes, but on searching my log, I only found a 31cm observation from Bargo on a very good night with a ZLM of 6.4 and good seeing back in 2001.

x186 26' TF.

IC 5250, IC 5250A (PGC 69714), IC 5246, NGC 7358, IC 5249 and IC 5247 all appear in the one group over 2 fields.

IC 5250 Mag 12.1p Size 2.9'. IC 5250 and -50A are a merged halo that contain distinctly seperate nuclei, -50 is the W most of the pair and the fainter. The combined halo is 1.75' x .25' in PA 90, rises broadly and slightly to the -50 nuclei, with the halo containing no apparent zoning except for the small 10" diameter moderately brighter spot core/nucleus.

PGC 69714 (IC 5250A) Mag 12.2p Size 2.7'. IC 5250 and -50A are a merged halo that contain distinctly seperate nuclei, -50 is the W most of the pair and the fainter. The combined halo is 1.75' x .25' in PA 90. The E end contains the -50A condensation, which is the brighter and is about 30-40" apart in PA 90. Rises broadly and moderately to the -50A nuclei which contains a 10" moderately brighter spot type core/nucleus which is somewhat brighter than the counterpart.

IC 5246 Mag 14.7 Size 1.0' x 0.6'. This eg is 10' N of the IC 5250 pairing. From that pairing, about 8' due N is a longish, thin RA Tri of mag 12-13 *s, to the NW of this is a rectangle of mag 13 *s which is about 5' x 2'. in PA 0. -46 appears to the W of the Tri and S of the rectangle. This is the 2nd brightest of the group (treating -50 as one object). This eg is pretty straightforward to see, round moderately faint, maybe 40" diameter rising slightly to the centre.

To the NE 5' and running beside the rectangle is IC 5249. IC 5249 Mag 15.0 Size 1.3' x 0.4'. A very small weak glow in PA 120, this is a very difficult eg to see and only occasinally visible as just about the thinest thing I've yet seen, it appears as 3' x <5" with the width of a strand of hair. No brightening to the axis or otherwise is detected. At the W end of the tip is a mag 15.5 *.

NGC 7358 Mag 13.8b Size 1.9' x 0.5'. Found 8' SW of IC 5250, there is a line of 4 faint *s in PA 45, the 3rd brightest is mag 13 and this eg appears very near it to the SE. Elongated in PA 170, 50" x 20", moderately faint and rising broadly and slightly to the centre.

IC 5247 Mag 15.0 Size 1.3' x 0.4'. A very small weak patch in PA120, 30" x 20" with a weak central brightening. Very faint it is , 15' SE of NGC 7358.


I can remember the night at Mudgee with the 18" (in July I think) and IC 5249 was just about the most beautiful, faint straight slash of gossamer imaginable -- really lovely. Dunno why I didn't do notes. Being July it maybe that it was very, very late (early) and had run out of motivation to make notes.

So Dunlop saw IC 5250 but not NGC 7258 and J Herschel missed the lot eh !

None of 'em are bright (well IC 5250 isn't too bad) and it is not entirely surprising they could be passed over.


Thanks Glen!



Best

Les D

[glenc]

Thanks Les for the notes. Herschel probably missed IC5250 because he was busy making notes on h3953 = NGC7358.
PGC 47847 (mag 10.6) is another long thin galaxy. It is 2.4 degrees NE (pa36) of omega Cen. The attached wikisky.org image is 28' x 28'

[glenc]

The open cluster Dunlop 224 = Harvard 6 is about 45' north of alpa in Musca.
Dunlop found it in 1826 and described it as " An exceedingly faint nebula, extended in the direction of the meridian, about 4' or 5' in length, with a line or group of very small stars in it."
He found about 20 non NGC/non IC open clusters. They were not included in the NGC because John Herschel failed to see them.
The attached wikisky.org image shows beta Mus top left, H6 and alpa Mus lower right.