John Herschel's Southern Nonexistent rngc objects




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Notes to Table 2:

1. NGC 241 was recorded once by Herschel, describing it as a "vF, R, nebula or group (We are now fairly in the Nubecula Minor, and the field begins to be full of a faint perfectly irresolvable nebulous light)." NGC 242 was observed three times: "pL, vF, R, vgbM; (in a sweep below the pole and ill seen)", "A binuclear nebula, or two, vS, R, running together" and "A small irresolvable knot in the bright part of the Nubec. Min." Herschel's positions for NGC 241 & NGC 242 show a substantial difference: Da = 6 sec, Dd = 36'. There is no object fitting his description and position for NGC 241 in Morel's (1989) Atlas. Kron (1956) and Lindsay (1956) list NGC 242 but have nothing near the position for NGC 241. Interestingly, Kron remarks that NGC 242 is a "double cluster."

2. In John Herschel's Northern Catalogue, he recorded NGC 723 as "pF, vS, R, vgbM." In a different sweep he recorded NGC 724 as "vF, pL, R, gbM, small star at PA 195°." Their coordinates differ by Da = 0.7 sec, Dd = 6' 35". In the Cape Observations, NGC 723 is recorded as "pF, R, gbM, 25 arcseconds. No other neb within 15' all round. (N.B. This remark shows that the nebula No. 167 of my former catalogue is really identical (as there suspected) with III.460."

3. NGC 1344, I.257, was discovered by William Herschel. He called it "cB, iR, vgmbM, 1.5' diameter." H I.257 was noted as h 2542 by John Herschel, who wrote: "R.A. by working list; P.D. [north polar distance] roughly taken; Transit missed while observing another nebula." On the next sweep, John Herschel recorded NGC 1340 (h 2539) as "vB, lE, psbM, 45 arcseconds across." Dreyer (1888) notes in the NGC: "h 2539: it may be identical with I.257 (h 2542), for [John Herschel] has only one observation of each (in different sweeps) and gives but a rough place for h 2542." It the Notes to the Index Catalogue, Dreyer wrote: "[NGC 1340] To be struck out - Swift." The ESO/Upps notes: "NGC 1340 Dec 10' off, NGC 1344 RA 0.4 m off."

4. NGC 1457 was first recorded as "pB, vmE, glbM, a ray nebula, 4' long, 20 arcseconds broad, pos = 38°." On a second occasion Herschel described it as "A ray nebula (vmE), vgpmbM; 2' long, position = 42.3°; 38° is no measure [only an estimate]." His final description reads: "F, vmE in pos = 39.5°, 3' long." NGC 1448 was only recorded once, as "pB, vL, vmE, 3' long, 20 arcseconds broad, position = 221.6°." The coordinate differences are Da = 52 sec, Dd = 12". Herschel's descriptions for NGC 1457 and NGC 1448 match closely. The discrepancy in position angles can be explained by assuming he calculated NGC 1448's PA incorrectly, inadvertently adding 180°; the correct measure would then have been 41.6°, which agrees well with NGC 1457's average measure of 40.9°. (See also Cape Observations, page 52, h2327, NGC 134: Herschel gave the PA first as 227° and on a second occasion as 47.96°.) Both ESO/Upps and the MCG list the PA as 41°. Shapley (1935:113) notes that NGC 1457 "should be dropped . . . the same as NGC 1448, as noted by Stewart." The ESO/Upps identifies ESO 249-G016 = NGC 1448 = NGC 1457. The MCG identifies MCG-07-08-005 as NGC 1448. Both sources list the coordinates as a 03:44:32, d -44° 38.6. De Vaucouleurs (1965:578) states that NGC 1448 is one of the five brightest members of the NGC 1433 galaxy group; he does not mention NGC 1457.

5. NGC 1649 was recorded only once by Herschel as "F, R, gbM; 30 arcsec across." NGC 1652 was observed three times and never in the same sweep as NGC 1649. Herschel described it as "vF, S, R, gbM; 12 arcsec across"; "vF, S, R" and "F, R, gbM, 35 arcsec across". The coordinate differences are Da = 5.9 sec, Dd = 8.6'. Shapley and Lindsay (1963) note only NGC 1652 (measured at a 04:38.2, d -68° 40) and give the diameter as 35 arcseconds. Their position for NGC 1652 corresponds well with Herschel's measure of a 04:38.4, d -68° 40.2'. The ESO/Upps comments: "10 degree [sic] error in NGC for 1649."

6. Herschel has one observation of NGC 1855 and five observations of NGC 1854, which he called "a cluster nebula . . . second of three objects." The other two objects are NGC 1850 & 1858. His first observation of this group recorded NGC 1850, 1855 & 1858. In three sweeps he recorded NGC 1854 & NGC 1858 and in another he recorded NGC 1850, 1854 & 1858. This group lies in a straight line spanning 12' of sky. In a note attached to NGC 1855 Herschel wrote: "This obs. must refer to the general cluster in which the former [NGC 1854] is situated as a nebulous-looking knot - a combination of the most ordinary occurrence in the Nubecula Major, though very rare in other parts of the heavens."

7. NGC 2442-3 is a field galaxy in the Dorado Cluster (Shobbrook, 1966). Herschel catalogued a brighter portion of the galaxy as a separate object. Concerning NGC 2442, the SGC notes: "NGC 2443 is a part of this galaxy."

8. Herschel recorded NGC 6216 on three occasions, and NGC 6222 on only one occasion. He described NGC 6216 as "p rich cl of S stars, 11th mag and under, broken up into two or three groups; fills two-thirds of field [ 10' ]"; "a round cluster of 13th mag stars, gbM; 4'; with two appendages of stars, north and south, making together a long cluster" and "p rich, R, p comp M, vlbM, 4' diameter, stars discrete 12..15th mag and fainter." NGC 6222 was recorded as "vL, v rich cl, not brilliant, not materially comp M, full 20' diameter, stars 12..13th mag." Although Herschel's descriptions do not match very well, particularly with respect to the apparent diameter, his positions for these two clusters are reasonably similar (Da = 1 min 22 sec, Dd = 20"). Since he only recorded NGC 6222 once and observed NGC 6216 afterwards, these two objects are likely equivalents. Collinder (1931) notes: "The cluster observed on [the Franklin-Adams charts] is about midway between [the NGC positions for NGC 6216 & NGC 6222]. No other observer than [John Herschel] has noted both clusters. Thus it probably is one and the same." Collinder describes the cluster as measuring 3.8' x 3' in PA 80°, containing 22 stars with an integrated magnitude of 10.1. He notes that the outline is not well defined, there is no appreciable concentration, the cluster stars are not apparently brighter than the surrounding stars, no bright stars stand out from the others and it is situated in a dense region. Lynga (1987) cross-lists NGC 6216 with NGC 6222 and Collinder 314.




Table 3. No Reason Given In RNGC For Nonexistence

NGC

NGC

NGC 2000.0

SGC

ESO/Upps

Notes

1523

3 vF stars

3 vF stars, not nebula

Four stars

----

----

1592

----

Only faint star

Galaxy

421-IG002

1

1639

3 stars in trng

3 stars in triangle

Three stars

----

----

1891

----

Nonex (R)

----

362-?020, No cluster

2

1963

----

Galaxy

Not listed

363-SC005

3

2886

----

Three stars

Three stars

565-?005

----

4776

----

Nonex (R)

----

Not listed

4

4778

----

Nonex (R)

----

Not listed

4

5670

----

Galaxy

Galaxy

272-G019

5

6725

----

Galaxy

Galaxy

183-G036

6

7140

? = 7141

= 7141

= 7141

189-G007

7

NONEX (R) in column 3 indicates that the NGC 2000.0 gives the RNGC as authority for the

'nonexistent' designation.

Notes on Table 3:

1. Cape Observations: "vF, vS." Howe, using a 20-inch refractor, reported only faint stars at

Herschel's position. The SGC remarks: "27' error in NGC declination."


2. Cape Observations: "A large scattered cluster, which more than fills the field. Stars 10..12th

mag. Place that of a double star, the chief star."


3. Cape Observations: "The cusp of a cluster of stars, 8..11th mag, arranged pretty exactly in a

figure of three with appendages. Star 8th mag in cusp taken." Note the NGC 2000.0's reference to

a galaxy. The ESO/Upps notes: "Open cluster, class II2" and gives the major axis as approximately

12'. NGC 1963 is not listed in MCG, RC2 or SGC, or by Lynga (1987). Paturel et al. (1991)

however lists NGC 1963 as a galaxy at a 05:33:12.8, d -36° 23.9. Herschel's description is clearly

not that of a galaxy.


4. Cape Observations, NGC 4776, h3437: "vF, S, R, vlbM; the preceding of a double nebula."

NGC 4778, h3438: "vF, S, R, vlbM, 15 arcseconds; has a star south-following; the following of

two." Herschel notes: "II-559 is not noticed as double in Sir W. Herschel's description." It is clear

that he thought he was observing II.559, which is listed as NGC 4759 by Dreyer. II.559 was

discovered by William Herschel in 1785 and described as "F, S." The NGC, drawing on further

observations by d'Arrest and Tempel, describes it as "pL, double, star 10th mag 2' south-

preceding." The RNGC notes that NGC 4759 is in contact with NGC 4761, a galaxy discovered

by Tempel and described as "eF, eS, 1' following the double nebula II.559." Neither NGC 4776

nor NGC 4778 are listed in the MCG, MERCG or RC2. Neither NGC 4759, NGC 4761, NGC

4776 nor NGC 4778 are listed in the ESO/Upps. The MCG lists MCG-01-33-036 = NGC 4759

and MCG-01-33-037 = NGC 4761. Paturel et al. (1991) notes that NGC 4764 = NGC 4778.

NGC 4764 was discovered by Tempel and is described in the NGC as "eF, eS, south following

double nebula II 559."
5. Cape Observations, July 1834: "Very faint, small, slightly extended, between 2 stars 13 and 14th

mag, forming northern side of a trapezium of four stars; one of the others is 8th mag." April 1836:

"Very faint, extended, between 2 stars and has a large star south-preceding." The SGC notes:

"Double star superposed 0.6' south preceding. Bright star 2.2' south preceding."


6. Cape Observations: "eF, pL, R. The R.A. not observed, but the observations immediately

preceding and following being 48min and 53min, it is probably between those limits." The R.A. in

the SGC, precessed to 1830.0, is 48 min 10 sec.
7. Herschel observed NGC 7140 (h3892) and NGC 7141 (h3893) on two consecutive nights. The

former he described as "Pretty faint, round, gradually brighter in the middle, 35 arcseconds" and the

latter as "Faint, large, round, first gradually then pretty suddenly a little brighter in the middle."

For NGC 7140 he recorded a declination of -57° 20' 25" and for NGC 7141 recorded -56° 21' 53". He

commented: "It is not improbable that [NGC 7141 and NGC 7140] are identical, one or other being

mistaken one degree in polar distance. Still, as both observations are clearly written . . and, as the

difference of polar distance even then is rather considerable (1' 28") I have thought it necessary to

enter them separately." Paturel et al. (1991) notes that NGC 7140 = NGC 7141.

TABLE 4.

RNGC OBJECTS LISTED AS NOT FOUND OR MISSING

--------------------------------------------------------------------------------------

NGC NGC 2000.0 SGC ESO/Upp Morel Notes

--------------------------------------------------------------------------------------

1243 Galaxy Not listed Not listed 1

1269 = 1291 = 1291 301-G002 2

1412 = IC 1981 = IC 1981 482-G029 3

1436 = 1437 = 1437 358-G058 4

1520 Open cluster 032-SC005 5


1557 Nonex (R) 055-**015 6

1570 = 1571 = 1571 250-G019 7

1884 Nonex (R) = 1882, 085-SC057 Nonexistent 8

1911 Nonex (R) 085-SC070 Open cluster 9

1915 Nonex (R) 085-SC071 Four stars 10
1991 Nonex (R) = 1974, 085-SC089 Nonexistent 11

1998 Galaxy Galaxy 204-G015, = 1995 ? 12

2132 Asterism 120-?022 13

2382 = 2380 = 2380 492-G012 14

3157 = IC 2555 = IC 2555 435-G051 15

3505 Nonex (R) Not listed 16

4832 Galaxy Galaxy 323-G051 17

4994 = 4993 = 4993 508-G018, 575-G065 18

6082 Nonex (R) Not listed 390-?001 19

6335 Nonex (R) Not listed 454-**010 20

6360 Nonex (R) Not listed 454-**020 21

6398 Galaxy Galaxy 139-G018 22

6403 Galaxy Galaxy 139-G019 23

6415 Nonex (R) 393-?018 24

6476 Nonex (R) 456-?008 25

6588 Not found 103-**014 26

6630 Galaxy Galaxy 103-IG026 27

7021 = 7020 = 7020 = 7020, 107- G013 28

7202 Galaxy Not listed 467-*A004, Star 29

7355 Nonex (R) 406-G006 345-G047 30

7655 Galaxy Galaxy 077-G018 31

--------------------------------------------------------------------------------------

Notes to Table 4:

1. NGC 1243 is one of a group of three NGC entries in Eridanus. Both William Herschel and the

Earl of Rosse (Parsons, 1926:158) saw two objects, NGC 1241 (II.286) and NGC 1242 (III.591),

with NGC 1242 to the northeast of NGC 1241. When John Herschel recorded NGC 1243, he

noted "position from the other [NGC 1241] = 120°", which places NGC 1243 to the southeast of

NGC 1241. Perhaps Herschel's measure of the PA is incorrect; see NGC 1457/1448, Table 2,

Note 3. If he made a +90° error, the PA would be 30°, placing NGC 1243 to the northereast of

NGC 1241. Since the Herschel's descriptions for NGC 1242-3 match ("eF, stellar" and "eF,

round") they might refer to one object. However, in the Notes to the NGC, J.L.E. Dreyer writes:

"It is very curious that nobody had ever seen more than two of these three at the same time, until I

observed them all three at Birr Castle on Nov. 6, 1877." The pair NGC 1241-2 is also known as

Arp 304. NGC 1243 is not listed in MCG, RC2 or ESO/Upps.


2. Herschel recorded NGC 1269 as "vB, R, gbM (hazy)." The R.A. he recorded was 03:08:35.6.

In the same sweep he recorded NGC 1291 as "vB, R, gbM, 1.5' (hazy)" with an R.A. of

03:11:04.3. Both observations have the same declination. During a later sweep he recorded NGC

1291 again, describing it as "a globular cluster, vB, R; first g then svmbM; r, mottled, but not

resolved." He noted the R.A. as 03:11:14.4, commenting: "There must have been a mistake of 10

seconds in reading or registering the chronometer in one or other of these observations. The

reductions of both are correctly performed." On 3 December 1901, R.T.A. Inness, observing with

the 7-inch refractor at the Royal Observatory, Cape of Good Hope, failed to find this object: "Not

visible in the 7-inch. This is perhaps the same as Dunlop 487 [NGC 1291], observed by h on the

same night. h gives for the latter exactly the same declination and description as for h 2518 [NGC

1269]. Dunlop 487 was well seen on the night that h 2518 could not be found". The ESO/Upps

has an entry for NGC 1269, ESO 300-?-021, and comments: " = 1291? R.A. of NGC 1291 off 2.5

minutes." The SGC describes the appearance of NGC 1269 on a photographic plate as

"overexposed nucleus, short bar, extremely faint knots on outer ring: 8.1' x 7.0'."


3. NGC 1412 was recorded once by Herschel as "F, S, E, gpmbM, 15 arcseconds; has a star sf

distance 2'." IC 1981 was recorded by Swift as "eF, eS, lE, star close nf." The SGC remarks:

"40' error in the NGC declination." Paturel et al. (1991) notes that NGC 1412 = IC 1981.
4. Herschel observed NGC 1436 twice. On the first occasion, it was "vB and evidently a globular

cluster . . . observed past meridian, clouds having prevented its place being secured at the time of

transit." On the second occasion, he wrote: "B, pmE, pgbM. The place is taken from Mr Dunlop's

Catalogue, but I have reason to believe this RA too great and the NPD also materially in error -

perhaps 126 35' [Dunlop had 126 45'] would be preferable. It was found by sweeping past the

meridian." Although he never gave a position for this object, he did record one for NGC 1437,

observed in a different sweep, which he described in the Cape Observations as "F, vL, glbM, R, 4

arcseconds." Clearly, four arcseconds can hardly be considered "very large", and was dropped

from his 1864 Catalogue. According to Herschel's size scale, "very large" described objects with a

diameter 8' to 10'. Herschel gave coordinates for NGC 1436 in his 1864 work, which differ from

his position for NGC 1437 by Da = 13 sec, Dd = 16.1'. The MCG lists MCG-06-09-025 = NGC

1437, recording the diameter as 2.2' x 1.4' with an integral magnitude of 12.9. The SGC and

Paturel et al. (1991) note that NGC 1437 = NGC 1436 = ESO 358-G058. The disagreement

between Herschel's descriptions remains a puzzle.


5. Cape Observations: "A poor cluster of about a dozen stars 9..12th mag within a space of about

5'." Neither Lynga (1987), Ruprecht, Balazs & White (1981) nor Collinder (1931) list NGC 1520.


6. Cape Observations: "A star 7th mag chief of a cluster 8th class - about 20 in number, loose and

straggling." Herschel's term "8th class" refers to "Coarsely scattered clusters of stars." The

ESO/Upps catalogue comments: "concentration of stars." Neither Lynga (1987), Ruprecht, Balazs

& White (1981) nor Collinder (1931) list NGC 1557.


7. Herschel recorded NGC 1570 as "F, S, R, gbM, 20 arcseconds." NGC 1571 was recorded in a

different sweep as "vF, S, R, 15 arcseconds, gbM, has a double star N.f." In the RNGC, NGC

1571 is noted as having "a double star 3' north." The ESO/Upps notes: "NGC 1570 Dec off 10

min."
8. NGC 1884 was recorded as "eF, 2' diameter." NGC 1882 was recorded in the same sweep and

described as "pF, R, vgvlbM, 3' diameter, mottled (resolvable)." The coordinates are reasonably

similar (Da = 29.5s Dd = 2' 10") so that both entries may refer to the same object; it is strange

however that both objects were recorded in the same sweep. Shapley and Lindsay (1963) recorded

NGC 1882 as an open cluster, noting that it is "irregular, resolved." They do not list anything at

the coordinates for NGC 1884.
9. Herschel recorded NGC 1911 as "F, R, gbM; 30 arcseconds. Among many stars." Morel

(1992) classifies it as a small and faint open cluster. The ESO/Upps notes: "NGC Dec off 5'." See

also note 10 below.
10. NGC 1915 is recorded as "eF, pL." Herschel notes: "Possibly the same with No. 2826 [NGC

1911], but the nebulae are so crowded that they may with equal probability be different ones."

The ESO/Upps notes: "NGC Dec off 4'." Morel (1992) notes: "Four stars, no cluster."
11. NGC 1974 is one of a group of objects in the LMC which Herschel described as a "great line of

rich clusters all connected by abundance of irregularly scattered stars." The easternmost object,

NGC 1974, was recorded by Herschel during Sweep 512 as "the following part of a large irregular

cluster which extends obliquely across the field." During Sweep 760 he recorded NGC 1991 as

"the fourth of a great line of rich clusters, connected by abundant irregularly scattered stars." Both

descriptions refer to the last object in the grouping, and since their coordinates are very similar (Da

= 56s Dd = 15"), these objects are likely to be equivalent.
12. Herschel recorded NGC 1995 and NGC 1998 on the same night in December 1834. The

former was described as "eeF, R, bM; exceedingly difficult and delicate. (Sky perfectly clear.) The

preceding of two." NGC 1998 was described as "eeF, R, bM; the following of two; in field to south

is a brilliant group of stars." However, his next sweep in this area, during January 1837, recorded

only NGC 1998: "F, R, gbM; north of a very bright group of stars, 1 of about 9th magnitude, three

or four 11th mag and fainter."


13. Cape Observations: "Chief star of a cluster 8th class of about a dozen bright and some smaller

stars."
14. Herschel recorded NGC 2380 as "Pretty faint, round, very gradually much brighter in the

middle, 40 arcseconds; in a rich field." The coordinates for NGC 2382 were roughly determined,

and it is described as "Pretty faint, round, brighter in the middle, 30 arcseconds; nearly on meridian

of Eta Canis [Major], or perhaps somewhat preceding." Indeed, Eta CMa lies almost exactly 2°

south of NGC 2380.


15. Herschel first recorded NGC 3157 in January 1835; he described it as "Very faint, elongated, 30

arcseconds; has a star about 8th mag south-preceding." Then in February 1836 he wrote:

"Looked for but not found by [these coordinates]. However, as no RA is noted, perhaps it was

looked for too late. The obs of [January 1835] is positive, and correctly reduced." This object

was recorded by Delisle Stewart, who examined photographic plates taken with the 24-inch Bruce

refractor at the Arequipa station of the Harvard College Observatory. Stewart's object, IC 2555,

was recorded as "Extremely faint, very small, extremely elongated in PA 45°, considerably brighter

in the middle." The SGC notes: "Almost spindle. Note correction to NGC dec."


16. This object was discovered by Herschel on May 19, 1836 during Sweep Number 700, which

was carried out "South of the Zenith" [Evans et.al. 1969:241]. Listed as h3312, it is described as:

"Pretty faint, small, round, gradually a little brighter in the middle. Has a star 14th mag near." The

1830.0 coordinates are given in the Cape Observations as R.A. 10h 54m 20.9s, NPD 104° 34' 47".

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