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Old 13-09-2024, 03:27 AM
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Dunlop’s 50 Galaxies

Scotsman James Dunlop set up his homemade 9 inch (23cm) aperture speculum reflector behind 91 Marsden St. Parramatta, NSW in April 1826. He lived in what is now the southern part of the Woolpack Hotel. On April 29 he discovered the first two galaxies. The last 2 of his 50 galaxies were found on November 24, 1826.

His 9 foot (274 cm) long telescope pointed south. On clear dark nights he moved it up and down sweeping the sky for clusters, nebulae and galaxies with a low power eyepiece. When one was discovered he recorded its RA using a sidereal clock, SPD (90-declination) and a description using a faint lantern. A ladder was needed for some objects, his RA was often out by 10’.

In only 7 months Dunlop found 155 NGC and IC open clusters, 50 galaxies, 40 nebulae, 29 globular clusters and 4 planetary nebulae. Many of these were in the two Magellan Clouds. He also mistakenly included faint double stars in his catalogue of 629 clusters and nebulae, because his telescope had poor resolution.

The attached file lists his 50 galaxies. The brightest is Cen A = NGC 5128, the faintest and smallest is NGC 1483 and the longest is NGC 4945. John Herschel (JH) thought that NGC 1483 was too faint for Dunlop to see. The table gives the NGC or IC number, the constellation, the galaxy sub-type, the 1826 month and day found, the visual magnitude, the size (in arc-mins) and some comments.
The image of NGC 1483 is from the HST.
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Old 13-09-2024, 03:44 AM
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James Dunlop’s descriptions of his 50 galaxies.

Steve Gottlieb's NGC/IC Notes on Dunlop's galaxies are as follows
http://adventuresindeepspace.com/steve.ngc.htm

NGC 55
James Dunlop discovered NGC 55 = D 507 = h2315 on 7 Jul 1826 from Parramatta, New South Wales. Using his 9-inch f/12 speculum reflector, he described it as "a beautiful long nebula, about 25' in length; position N.p. and S.f., 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." Dunlop observed the galaxy on 4 nights and made a simple sketch (Figure 21).

NGC 134
James Dunlop discovered NGC 134 = D 599 = D 590 = h2327 with his 9" reflector on 7 Jul 1826. His description for D 599 reads "very faint nebula, about 25" diameter, rather elliptical. North of Eta Caelae Sculptoris. There are four small stars south of the nebula in the form of a lozenge." His position is 22' NNW of the galaxy but the description of the four nearby stars to the south clinches the identification. For D 590 he logged (handwritten notes), "a very faint round nebula, about 2' diameter, rather brighter in the middle, il defined. South following Eta Sculptoris."

NGC 300
James Dunlop discovered NGC 300 = D 530 = h2359 on 5 Aug 1826 with his 9" speculum reflector. Based on 3 observation he described "a pretty large faint nebula, irregular round figure, 6' or 7' diameter, easily resolvable into exceedingly minute stars, with four or five stars of more considerable magnitude; slight compression of stars to the centre." There are several superimposed Milky Way stars. In his first observation, he noted "a pretty bright small star south of it [probably mag 8.7 HD 5229] - and two or three minute stars north, and following involved in the nebula."

NGC 625
James Dunlop discovered NGC 625 = D 479 = h2426 on 2 Sep 1826 with his 9" reflector and described "a very faint nebula, of a round figure, with two or three minute stars in it near the meridian". His single position is ~8' too far E. John Herschel logged on 5 Sep 1834, "B, pL, mE, nearly in the parallel; pretty much brighter middle." On a second sweep on 4 Dec 1836 he called it "B, mE, gradually brighter in the middle, 80"." The next night he logged the galaxy again as "B, L, mE, gradually brighter in the middle, 1.25' long."

NGC 986
James Dunlop discovered NGC 986 = D 519 = h2487 on 5 Aug 1826 with his 9" reflector at Parramatta (near Sydney) and described "a faint nebula, of an irregular round figure, about 30" diameter, north of a bright small star." His single position is 9' SE of NGC 986 (typical error) and there are no other nearby brighter galaxies that he might have been picked up instead.

NGC 1291
James Dunlop discovered NGC 1291 = D 487 = h2521 on 2 Sep 1826 with his 9" reflector at Parramatta and recorded "a pretty bright round nebula, about 1.5' diameter, very bright and condensed to the centre, and very faint at the margin; with a very small star about 1' north, but not involved.". His single position was 4' too far ESE. Probably due to a clerical error, John Herschel included two entries for this galaxy in his Cape Catalogue from his observation on 1 Nov 1836 - namely, h2521 (later NGC 1291) and h2518 (later NGC 1269). The RA for h2518 was 2.6 minutes of time too small, though otherwise the two entries are essentially identical and neither he nor Dreyer caught the error. In 1901 Robert Innes was unable to find NGC 1269 with the 7" refractor at Cape Town and first suggested it was identical to NGC 1291.

NGC 1313
James Dunlop discovered NGC 1313 = D 206 = D 207 = D 205? = h2528 on 27 Sep 1826. He described D 207 as "a faint ill defined nebula about 1 1/2' diameter, round figure, a very minute star south slightly involved in the margin - a bright star about 20' south of the nebula." His reduced position was 13' too far east but the declination was incorrectly transcribed, so his published position was off by 30'. D 206 was described as "a faint ill-defined nebula, rather extended in the direction of the meridian [N-S], with several exceedingly minute stars in it." Finally D 205 was placed 1.4° too far west and 10' small, but the description fits: "a very faint small nebula, north following a pretty bright star [mag 8.7 HD 20533]; a very minute star is between the bright star and the nebula [mag 10 SAO 248769]."

NGC 1316
James Dunlop discovered NGC 1316 = D 548 = h2527, along with NGC 1317, on 2 Sep 1826. He described "a rather bright, round nebula, about 1.5' diameter, gradually condensed to the centre." On 24 Nov 1826, he noted "a group of pretty bright small stars following, which matches NGC 1316. Dunlop discovered six members of the Fornax cluster, though most (15) were found by John Herschel.

NGC 1317
James Dunlop discovered NGC 1317 = D 547 = h2529, along with NGC 1316, on 2 Sep 1826 with his 9" reflector from Parramatta. He described "a small faint round nebula about 15 arcseconds in diameter." and his position is ~15' too far ENE. John Herschel first observed the galaxy on 22 Oct 1835 and noted "pB, S, R, pretty suddenly brighter in the middle." His second sweep he recorded it as "pB, pL, 1' diameter; a miniature of the last neb. of this sweep." Julius Schmidt independently found the galaxy on 19 Jan 1865 and thought it was new, because JH made an typo of 20 degrees in NPD for h2529 in the CGH catalogue. JH corrected the NPD in the addendum of the catalogue, but apparently Schmidt didn't check.

NGC 1350
James Dunlop discovered NGC 1350 = D 591 = h2545 on 24 Nov 1826 with his 9" reflector from Parramatta, NSW. He noted (single observation) "a very faint small ill-defined nebula, south-following [preceding] a small star." He probably was referring to the mag 7.2 star 6' NE. His position was fairly poor, nearly 15' to the SE.

NGC 1365
James Dunlop discovered NGC 1365 = D 562 = h2552 on 2 Sep 1826. He described "a pretty large faint round nebula, about 3 1/2' diameter, gradual slight condensation to the centre, very faint at the margin." He made two observations but his published RA was off by a full 10 minutes of time. His handwritten notebook positions are only 9' E and 9' SE, so he clearly made a transcription error (of 3 minutes in time) in his catalogue. As a result, Dunlop wasn't credited with the discovery in the GC or NGC.

NGC 1380
James Dunlop discovered NGC 1380 = D 574 = h2559 on 2 Sep 1826 with his 9" reflector at Parramatta. He recorded "a rather faint pretty well-defined elliptical nebula, about 1' long, and 50" broad, a little brighter to the centre." His single position was well off, 19.5' too far ESE, but this is brightest single galaxy he likely picked up. John Herschel also made a single observation on sweep 635 (19 Oct 1835) and logged, "very bright; large; round; pretty suddenly brighter towards the middle; A fine nebula." He added: "The obs. of the place like that of Dunlop 591 above was lost by setting the instrument on the place given in Mr Dunlop's Catalogue, and relying on his RA (3h 31m) which is too great, instead of sweeping over them, when they could not have escaped being regularly taken." In 1865 Julius Schmidt measured a more accurate position with the 6.2" refractor at the Athens Observatory.

NGC 1433
James Dunlop discovered NGC 1433 = D 426 = h2580 on 28 Sep 1826. His description (based on two observations) reads "a very faint nebula, about 1' diameter, rather elliptical in the parallel of the equator; with a brightish point or condensation of the nebulous matter, a little to the preceding side of the centre."

NGC 1483, mag 12.3, diam 2’
James Dunlop found D 428 on 2 Sep 1826 and described it as "An extremely faint ill-defined small nebula. A pretty large nebula (D 427) precedes this." Despite Herschel's comments below Dunlop's position lands very close to NGC 1483 and his position for NGC 1493, only 1.5° NNE and discovered the same night (perhaps immediately afterwards), is also an excellent match! So, perhaps Dunlop was first to discover NGC 1483. Of course, this implies D 427 is a spurious observation, as there's only a single galaxy here.

John Herschel described NGC 1483 = h2595 on 14 Dec 1835 as "pretty faint; round; very little brighter in the middle; 20". (Newly polished mirror, but the sky dull and haze forming; so that this may very possibly be Dunlop 428.)". His second observation reads "very faint; pretty large; round; very gradually a little brighter in the middle; 80" across. I feel convinced that this nebula is too faint to have been seen by Mr Dunlop. Put on the 9 inch aperture, could not discern the least trace of it. Mirror polished yesterday and in high beauty. Sky superb."

NGC 1487
James Dunlop discovered NGC 1487 = D 480 = h2597 on 29 Oct 1826. He described "a very faint ill-defined nebula, with two or three very small stars in it, and a small star following." There is nothing at his published position, but 83 seconds of RA west is the interacting system VV 78 = PGC 14117 and the description fits. Glen Cozens states this is probably the faintest galaxy that Dunlop discovered (V = 11.9).

NGC 1493
James Dunlop discovered NGC 1493 = D 438 = h2600 with his 9-inch reflector on 2 Sep 1826 and described "a very faint nebula, about 1' diameter, round figure". JH first logged it on 14 Dec 1835 and noted "F, vL, R, very gradually little brighter middle, 3'; sky dull, a haze forming." On a second sweep he was critical of Dunlop's discovery and commented "faint; large; round; very gradually a little brighter in the middle; 2.5' across. With 9" aperture, and a mirror newly polished yesterday, and in high beauty, it is barely possible to discern with the utmost attention that this nebula exists; but to have discovered it with that aperture and power 180 would have been quite out of the question; possibly, however, 90 might show it better." Despite Herschel's skepticism, Dunlop's position is unusually accurate. ______
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Old 13-09-2024, 03:50 AM
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James Dunlop’s descriptions of his 50 galaxies cont

Steve Gottlieb's NGC/IC Notes on Dunlop's galaxies are as follows
http://adventuresindeepspace.com/steve.ngc.htm

NGC 1512
James Dunlop discovered NGC 1512 = D 466 = h2607 on 29 Oct 1826 and described "a small faint round nebula, about 25" diameter, a little brighter in the centre: a star of 10th or 12th magnitude preceding the nebula [HD 25651]." Dunlop made a single observation and his position is 10' SE of the galaxy (typical error).

NGC 1515
James Dunlop discovered NGC 1515 = D348 = h2609 on 5 Nov 1826 using his 9-inch f/12 reflector from Parramatta. He found "a very faint nebula, about 35 arcseconds diameter. This precedes a group of small stars." His position is 1 min 15 sec of RA too far east (typical error) and a group of mag 12 stars follows, clinching the identification. John Herschel first observed this galaxy on 5 Dec 1834 and logged "B, L, very much extended, gradually brighter in the middle; 3' l, 40" br".

NGC 1527
James Dunlop discovered NGC 1527 = D 409 = D 429 = h2612 on 28 Sep 1826 and described "a very small and very faint round nebula, about 20" diameter." His position was 10' too far NE. D 429 is probably a duplicate observation with a 55' error in declination (too far north).

NGC 1532
James Dunlop discovered NGC 1532 = D 600 = h2621 on 29 Oct 1826. He described "an extremely faint ill-defined nebula, rather elongated in the direction of the meridian [N-S], gradually a little brighter towards the centre." His notes mention it was situated southwest of a pretty bright star, which is mag 7.0 HD 26799.

NGC 1543
James Dunlop discovered NGC 1543 = D 306 = h2627 on 5 Nov 1826 with his 9" reflector and described as "a small round pretty well defined nebula, 10" or 12" diameter, slightly bright to the centre, a bright star in the field south following." Dunlop's position is 11' too far south.

NGC 1553
James Dunlop discovered NGC 1553 = D 331 on 5 Nov 1826 and described "a rather bright nebula about 1' diameter, very faint at the margin, gradually bright to the centre: a small star north, and another south, both involved in the margin of the nebula. A group of very small stars north." Dunlop made a transcription error of 1 hour in RA so his published position is 1 hour too large. His two notebook entries are only 10' too far south. I'm surprised Dunlop apparently missed NGC 1549. He mentioned "a group of very small stars north", which are just off the south side of NGC 1549.

NGC 1559
James Dunlop discovered NGC 1559 = D 264 = h2634 on 6 Nov 1826. He made two observations with summary description, "faint round nebula, about 40" diameter, slightly bright to the centre; this is north preceding Theta Rhomboidis". His published position is 18' too far south (accurate in RA) as he overestimated the separation from Theta Ret.

NGC 1566
James Dunlop discovered NGC 1566 = D 338 = h2635 on 28 May 1826 with his 9" reflector from Parramatta and described "a pretty large round nebula, about 4' diameter, moderately and gradually condensed to the centre. A very small star near the following edge, not involved." His handwritten notes also mention a "pretty bright star precedes it and about 3' to 4' north", matching Mag 8.2 HD 27713, which is 5.4' NW of center.

NGC 1617
James Dunlop discovered NGC 1617 = D 339 on 5 Nov 1826 and described "a small round pretty well defined nebula, bright in the centre, NW of Alpha Doradus". His position was off by 11.5' (typical error) to the SE. John Herschel observed the galaxy on 5 Dec 1834 and logged (for h2651), "B, L, mE, first very gradually then very suddenly much brighter to the middle to a nucleus 5" in diameter; 3' long, 1' broad." The next night he reobserved it and noted "pB, L, mE, suddenly brighter in the middle, 3' long, 2' broad, pos. 105.8 degrees." His mean position is accurate.

IC 1633
James Dunlop discovered IC 1633 = D 437 = Sw. 11-13 on 5 Aug 1826 and recorded (single observation) "an extremely faint small nebula; round, with a very minute bright point in the center." Dunlop's position is 6.6' SW of ESO 243-046, but this is a typical error and there no other brighter galaxies nearby. Lewis Swift independently discovered this galaxy on 29 Sep 1897, assumed it was new, and logged Sw. 11-13 as "vF; S; R; no B* near; vF one following." In his 4th list from Lowe Observatory, the declination was off by 2° too far north, but this error was corrected in his large Astronomische Nachrichten (AN) table.

NGC 1672
James Dunlop discovered NGC 1672 = D 296 = h2665 on 5 Nov 1826. He described "a faint ill-defined nebula about 50" diameter, irregularly round with a small bright point near the preceding side, which I suspect to be a star; a pretty bright star about 20' south-preceding [mag 5.3 Kappa Dor] and also another following [mag 6.8 HD 30790]."

NGC 1792
James Dunlop discovered NGC 1792 = D 531 = h2730 on 4 Oct 1826 and described "a long or rather elliptical nebula, about 2' long and 50" broad, a little brighter in the middle, and well defined. There is a group of small stars on the north side."

NGC 1808
James Dunlop discovered NGC 1808 = D 549 = D 532 = h2740 on 10 May 1826. Based on two observations he described "a faint nebula, about 2.5' long, and fully 1' broad, extended S.p. and N.f.; a very minute star near each extremity, not involved." D 532 is another observation and he noted it was very similar to D 531 = NGC 1792 (observed together), but he made a large error (nearly 40') in declination.

NGC 1947
James Dunlop discovered NGC 1947 = h2855 on 5 Nov 1826 with his 9" reflector, although due to an oversight he failed to include it in his 1828 catalogue (NGC 6300 and Tr 9 are two more cases). His handwritten notes read, "a faint round nebula 25" or 30" diameter, pretty well defined, south following a small star." His position is 7' too far SW and 4' NNW is mag 9.7 HD 36355, consistent with his description.

NGC 2090
James Dunlop discovered NGC 2090 = D 594 = h2944 on 29 Oct 1826. He described "a small faint nebula, with a ray shooting out on the north side." Dunlop observed this galaxy only once and his position was only 3' SSW. The "ray" he mentions perhaps consists of 3 mag 13-14 stars. John Herschel recorded the galaxy twice, on 8 Jan 1836 (sweep 662) recording a "globular cluster, B; R; with an appendage to northward; 2.5' diameter." The following night he described it as "B, irreg R, gradually brighter in the middle; 3' long; 2' broad with stars appended. This RA to be preferred". Herschel called this galaxy a globular in the GC and Dreyer followed in the NGC.

NGC 4696
James Dunlop discovered NGC 4696 = D 510 = D 511 = h3424 on 7 May 1826. He described D 510 (from handwritten notes) as a "faint nebula, about 12" or 15" diameter, very ill defined at the edges, slightly condensed to the center, 14' or 15' south - rather preceding - a star 7th mag." His position was 16' too far NW. D 511 was logged as a "pretty large faint nebula." and his position was 12' too far SE. Neither of these positional discrepancies are unusually large.

NGC 4709
James Dunlop probably discovered NGC 4709 = h3428 = D 511? on 7 May 1826 and reported "pretty large faint nebula". His position (single observation) is 6.7' SW of NGC 4709.
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Old 13-09-2024, 03:55 AM
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James Dunlop’s descriptions of his 50 galaxies continued

Steve Gottlieb's NGC/IC Notes on Dunlop's galaxies are as follows
http://adventuresindeepspace.com/steve.ngc.htm

NGC 4945
James Dunlop discovered NGC 4945 = D 411 = h3459 on 29 Apr 1826. This is one of the first objects observed by Dunlop (2nd night in logbook) and the first galaxy he discovered, along with NGC 5128 the same night. His summary description reads, "a beautiful long nebula, about 10' long, and 2' broad, forming an angle with the meridian, about 30 [degrees] 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 extremeties, 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 the nebula is resolvable into stars [on 4 June], 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 first zeta Centauri." Dunlop made a total of 7 observations (sketch, Figure 17).

NGC 5128
James Dunlop discovered NGC 5128 = D 482 = h3501 on 29 Apr 1826, his second night recording deep sky objects -- NGC 4945 was discovered just 20 minutes earlier! Based on 6 observations, his summary description reads, "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 nebulae 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." His sketch (Figure 20) shows two parallel bands with a star between at one end.

IC 5250
James Dunlop discovered IC 5250 = D 255 = D.S. 768 on 5 Sep 1826 with his homemade 9-inch f/12 speculum reflector. He described a "small faint elliptical nebula in the parallel of the equator, about 25" long and 12" or 15" broad." His position is just 3' following this interacting pair of galaxies (similar in appearance to the Antennae). Interestingly, John Herschel discovered NGC 7358, which is just 11' SW, but apparently missed this galaxy, which is larger and brighter.

IC 5332
James Dunlop probably discovered IC 5332 = D 546? on 14 Jul 1826. He reported finding an "extremely feeble, ill defined nebula; it is at least 1' diameter. It seems rather elongated oblique to the equator; it is north following a bright star of the 7th-8th magnitude, and also north of two small stars." His position is 1° south and 1 minute of RA east of IC 5332, which matches his description: a 7th mag star is 13' SW and a 10th mag star (and two 12th mag) are close SW. This identification was suggested by Glen Cozens in his analysis of Dunlop's discoveries.

NGC 5643
James Dunlop probably discovered NGC 5643 = D 469 = h3572 on 10 May 1826 and recorded "an exceedingly faint, extended nebula, about 10' long; rather ill-defined." His position is just 5' east, but his size estimate is a very poor match (transcribed correctly from his handwritten notes). Perhaps he thought a nearby chain of stars was a nebula and the positional match is just a coincidence?

NGC 6300
James Dunlop discovered NGC 6300 = h3668 on 30 Jun 1826. He described (handwritten notes) a "faint round nebula, about 1 1/4' diameter, slightly condensed very gradually to the center - not very well defined at the edge. Preceding and forming a triange with two stars of the 7 and 8th mag." He made 4 more observations in July and Aug., but the discovery is missing in his catalogue, which I assume was an oversight (NGC 1947 is a similar case).

NGC 6744
James Dunlop discovered NGC 6744 = D 262 = h3776 on 30 Jun 1826 with his 9" reflector from Parramatta (20 km W of Sydney). His summary description based on 3 observations reads "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 mag preceding." His rough published position was 1 min 45 sec of time too far west (12' error).

NGC 6861
James Dunlop discovered NGC 6861 = D 425 = h3811 on 30 Jul 1826 and recorded "a very small faint nebula, about 15" diameter." There is nothing at his position, but Glen Cozens found he made a 1° transcription error (to the north) from his handwritten notebook position to his published catalog (verified). The corrected position is just 6' NW of NGC 6861, the brightest galaxy in the area.

NGC 7049
James Dunlop discovered NGC 7049 = D 406 = h3860 on 4 Aug 1826 and recorded "a small round nebula, about 12 or 15 arcseconds diameter, very bright immediately at the centre, resembling a small star surrounded by an atmosphere. This is N.f. a star of the 6th magnitude." His position was 4' ENE of center.

NGC 7083
James Dunlop probably discovered NGC 7083 = D 263? = h3870 on 28 Aug 1826 and recorded "a small faint round nebula, 20 arcseconds diameter, a little brighter in the middle, following a group of pretty bright stars." His position is ~20' too far west. John Herschel found this galaxy on 22 Jun 1835 and logged "F; L; R of lE; vgpmbM; 60"; resolvable; with long attention it appears mottled. Perhaps Dunlop 263, with 3 minute correction in RA." On a later sweep he noted "pB; pL; R; gradually brighter in the middle; 60"." First resolved as a "spiral nebula" on a plate taken at Harvard's Arequipa station around 1900.

NGC 7410
James Dunlop discovered NGC 7410 = D 518 = h3960 on 14 Jul 1826. His summary description based on two observations reads, "a very faint nebula extended preceding and following, about 1.5' long and 20 or 25 arcseconds broad; a little brighter in the middle, or rather nearer the N.p. extremity; the S.f. extremity is very ill defined." His handwritten notes specify the elongaton is SW-NE, clinching the identification.

NGC 7552
James Dunlop discovered NGC 7552 = D 475 = h3977 on 7 Jul 1826 and made 4 observations. He described the first member of the Grus Quartet as "a small faint nebula, rather elongated in the parallel of the equator, about 30" broad, and 40" long; there is a pretty bright point situated near the centre of the nebula: a small star precedes it."

NGC 7582
James Dunlop discovered NGC 7582 = D 476 = h3977 on 7 Jul 1826 and recorded "a small faint round nebula, about 30" diameter: a double nebula follow this [NGC 7590 and 7599]." John Herschel made a single observation on 2 Sep 1836 and described "pB, L, pmE, gradually brighter in the middle." His declination was 15' too large. NGC 7582 was first photographed by DeLisle Stewart at Harvard's Arequipa Station between 1898 and 1901 and the position was corrected.

NGC 7590
James Dunlop discovered NGC 7590 = D 477.1 = h3980 on 14 Jul 1826, along with NGC 7599 and recorded "two very small round nebulae [NGC 7590 and 7599], nearly the same RA, and differing about 1' in polar distances." His single position for the pair was over 30' too far west.

NGC 7599
James Dunlop discovered NGC 7599 = D 477.2 = h3981, along with NGC 7582, on 14 Jul 1826 and recorded "two very small round nebulae, nearly the same RA, and differing about 1' in polar distances." His single position was 30' too far W. John Herschel observed the pair of 2 Sep 1836 (sweep 728) and logged "F; pmE; gradually brighter in the middle; 3'; [the following of two]."

NGC 7689
James Dunlop discovered NGC 7689 = D 347 = h7689 on 5 Sep 1826 and described a "faint round nebula, about 20" diameter." His position was 17' too far ESE, but his notes also mention "preceding a small star" which matches NGC 7689.

NGC 7793
James Dunlop discovered NGC 7793 = D 608 = HN 4 on 14 Jul 1826 and recorded a "faint round nebula, about 2' diameter, with a very slight condensation towards the centre; a double star is north preceding" (2 observations). His position was 14' too far east (typical error) and the double star is probably a wide pair (~1' separation) about 8' N. Apparently John Herschel didn't observe this galaxy from South Africa.
______
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Old 13-09-2024, 08:02 AM
Saturnine (Jeff)
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Thanks for posting all lists of the James Dunlop discoveries, whether galaxies , planetary nebulae etc, they make fascinating reading and I can't wait to get out to dark skies again with 12.5'' dob, to hunt down some ( a lot )of them.
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Old 13-09-2024, 10:03 PM
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Agreed, this does whet the appetite to get out there and observe all those wonderful objects discovered by our own James Dunlop. Thanks for posting all this great information Glen.
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Old 14-09-2024, 01:19 PM
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Thanks Jeff and Joe.
Last night I looked at some galaxies with a 10" Dob at 109 times.
NGC 1433 was easy.
NGC 1483 and 1493 were difficult, I had to use averted vision.
I do have some light pollution.
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Old 15-09-2024, 05:52 AM
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Galaxies brighter than mag 12

1264 galaxies brighter than or equal to mag 12 were found visually and 36 were found using photography.
The 1264 were found by
Number, Name
726 William Herschel
270 John Herschel (William's son)
49 James Dunlop
40 Lewis Swift
18 Pierre Mechain (Messier's friend)

44 other people found 15 galaxies or less
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