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Entwurf: Exoplaneten vollständige Liste

Stern/Exoplanet[1] Sternbild Planetenname Masse
(MJ)[1]
Radius
(rJ)[1]
Dichte
(J)[2]
Umlaufzeit
(d)[1]
Große Halbachse
(AE)[1]
Exzentrizität[1] Bahnneigung[1] Entdeckung
(Jahr)[1]
Detektions-methode[1] Rektaszension (Grad)[2] Deklination (Grad)[2] Effektive Temperatur(K) Entfernung
(pc)[1]
Spektralklasse /Scheinbare Helligkeit[1] Leuchtkraft[3]

Kritische Fälle im NGC- ind Index-Katalog

1. NGC 116
The position precesses to RA 00 27 06.5, Dec -07 56 40, but there is nothing near that position, so the object could be listed as lost or nonexistent. Argument For PGC 1671 Being NGC 116: As noted above, PGC 1671 is the brightest galaxy "near" Ferrari's position, and being nearly due north of his position makes the error in position relatively simple. However, without any description save for "very faint" and the large error in its position, whether its identification as NGC 116 is even reasonable, let alone likely, is very uncertain.

2. NGC 411 = NGC 422? Historical Identification (and Misidentification): Per Dreyer, NGC 422 (= GC 231 = [JH 162], 1860 RA 01 04 28, NPD 162 30.9) is "very faint (in Nubecula Minor)", Nubecula Minor being the Small Magellanic Cloud. The second Index Catalog notes (per DeLisle Stewart) "only 3 extremely faint stars, close together, not a nebula". NGC 422 was long thought to be ESO 51 - SC 022 and is still listed as such in almost all references; so that object is discussed immediately following. However, as will be discussed here before finalizing this iteration of this page, it has now been shown that it is actually a duplicate observation of NGC 411. Discovery Notes [JH 162] refers to a list of Small Magellanic Cloud objects observed by Herschel at the Cape of Good Hope that were numbered separately from his usual method of numbering his observations. Physical Information: Given the duplicate listing, see NGC 411 for anything else.

3. NGC 832 = NGC 1226?(erledigtErledigt)
Historical Identification: Per Dreyer, NGC 832 (= GC 5222, d'Arrest, 1860 RA 02 02 17, NPD 55 07.6) is "faint, very small, 9th or 10th magnitude star to southwest". The position precesses to RA 02 10 36.5, Dec +35 32 14, but there is nothing there. For a time, a pair of faint stars 24 seconds of time to the east of d'Arrest's position was thought to be what d'Arrest saw, as there is a 10th magnitude star to their southwest; and for that reason, the pair is discussed immediately below. However, in mid 2016 Corwin noticed that there is a galaxy an hour of time to the east of d'Arrest's position that exactly matches his description, down to a 10th magnitude star to its southwest. Since d'Arrest is known to have made similar single-digit misrecordings of his observations in several cases, the identification of that galaxy as NGC 832 is essentially certain (changing d'Arrest's RA to 03 11 00.9 leads to a modern position of RA 03 11 03.1, Dec +35 24 30, less than 1.4 arcmin north northwest of the galaxy listed above, and the star to its southwest seems to make the identification certain). As it happens, that galaxy was already listed in the NGC as NGC 1226, so d'Arrest's misrecorded observation simply led to a duplicate entry; and due to the so recent realization of what went wrong, it is essentially certain that the galaxy will continue to be called NGC 1226, and NGC 832 will be relegated to the status of a duplicate entry.

4. NGC 940 = NGC 952?
Per Corwin's earlier notes, there was little doubt that Stephan misidentified his comparison star, so the offset from that reference (4m 25.61s west and 2' 48" north) automatically yielded an incorrect position. Corwin used those offsets with several other possible comparison stars, with no success. However, in a more recent note Corwin states that E. Esmiol's update of Stephan's observations omits NGC 952, and lists offsets for the position of NGC 940 that are identical to those from Stephan's measurements for what became NGC 952. As a result, there is no doubt that Esmiol's reduction of Stephan's observations proved that NGC 952 was simply an incorrectly calculated reduction of an observation of NGC 940. (Note: Although Esmiol's paper was published a century ago, it was essentially unknown or ignored for decades, and as a result it has only very recently resolved some problems with Stephan's observations; but this is the second or third time that I have run across this situation, so I will revise this entry to reflect the importance of Esmiol's work in a later iteration of this page.)

5. NGC 1037 = IC 243?
Perhaps NGC 1037 = IC 243: As noted in the title for this entry, I think it possible that NGC 1037 is a badly misrecorded observation of IC 243 (in which case Swift would be the original observer of that object). His list V contains a large number of objects observed on the same night as NGC 1037. All the others have (1900) declinations ranging from -8 to -16 degrees, and it seems odd that this object has a declination 6 degrees beyond the northern edge of that range. Usually, those looking for one of Swift's misrecorded objects assume that his declination is reasonable and his right ascension is off, but it appears likely that in this case the error is in his declination. Suppose that he made an error of five degrees in recording his observation, so that his published (1900) position should be read as RA 02 34 08, Dec -07 13 47, instead of Dec -02 13 47. This could have been caused by misreading his declination circle, or by writing such a sloppy "7" that he misread it as a "2" (either error is easy to make, and Swift's observations are riddled with similar mistakes). If this suggestion is correct, Swift's (corrected) position would precess to RA 02 39 05.0, Dec -06 47 53. This lies half a minute of time to the east and six arcmin to the north of IC 243, which is a positional error more typical of Swift's measurements, and NGC 1022 lies less than a quarter degree to the north of IC 243, which fits Swift's statement that a (much brighter) GC object was in his field of view. If the correction suggested here were only a degree or two, there would probably be general agreement that the identification of NGC 1037 as IC 243 is "reasonably certain". Given the much larger error required, whether this suggestion will become accepted is less certain; but Corwin agrees that it deserves mention, hence my decision to post this discussion and a corresponding image (namely, the second below).

6. NGC 1135 = NGC 1136?(erledigtErledigt) Obwohl alle konsultierten Quellen PGC 10800 als NGC 1135 und PGC 10807 als NGC 1136 identifizieren, weist Professor Seligman darauf hin, dass die von John Herschel für diese beiden Galaxien gegebene Beschreibung identisch ist und dass die Helligkeit von PGC 10800 zu schwach ist, entsprechend seiner Schriften. Professor Seligman sagt auch, dass NGC 1135 und NGC 1136 ein und dieselbe Galaxie sind, nämlich PGC 10807, (siehe Seligman): The position precesses to RA 02 50 45.2, Dec -54 57 49, less than an arcmin northwest of PGC 10807, so the identification with that galaxy should have been relatively certain. However, Herschel listed two galaxies in the region, the other one (GC 622 = JH 2499) being recorded as a few arcmin to the south, and there are two galaxies in the region, so it has been generally assumed for more than a century that the southern observation corresponds to the southern galaxy (listed as NGC 1136), and the northern observation to the northern galaxy (listed as NGC 1135). For that reason, despite the apparent equivalence of Herschel's GC 621 with PGC 10807, tradition is that PGC 10800 (the northern of the two galaxies) is the "actual" NGC 1135, and almost every reference I can find states that NGC 1135 = PGC 10800, and NGC 1136 = PGC 10807. However, Herschel's description of the two objects is identical, whereas the northern galaxy is much fainter than the southern one, and per Corwin if the much fainter northern galaxy really had been Herschel's GC 621, then he would have listed it as "extremely faint" instead of "faint", as it would have been one of the faintest objects ever observed by him. As a result, Corwin suggests (and I agree) that it makes far more sense to assume that GC 621 and 622 are duplicate observations of the same, brighter southern galaxy, with the recorded position for GC 621 being (as already noted above) relatively accurate, and the one for GC 622 being unfortunately well to the south of the correct position, due to an error in reducing its position. For that reason, in this catalog I have equated NGC 1135 and 1136, and relegated PGC 10800, which is still listed as NGC 1135 almost everywhere else, to the lower status of a historically important but mistaken identification.

7. NGC 2029 = N63A?
Viele Quellen sprechen dafür, jedoch einige auch wieder nicht....
NGC 2029 ist ein Eintrag im New General Catalogue (abgekürzt NGC) über eine Himmelserscheinung mit der Positionsangabe 5h 35m 20s, 157° 38.7′ North Polar Distance, 1860 und der abgekürzten Objektbeschreibung: pB, pL, R, gbM, in eLCl − übersetzt: besonders hell, besonders groß, rund, zur Mitte hin graduell heller werdend, in einem sehr großen Sternhaufen. Dieser Eintrag referenziert eine Beobachtung von James Dunlop, die 1828 publiziert wurde: A faint round nebula, 25″ oder 30″ diameter[1] sowie deren Bestätigung durch eine zweifache Beobachtung in den 1830er Jahren von John Herschel.[2] Als weitere Referenz wird ein von Herschel zwischenzeitlich erstellter Katalog[3] genannt, der diese Beobachtungen zusammenfasst, bei dem die Koordinaten aber in der Deklination rund 1,5° abweichen, ebenso wie dann im New General Catalogue: Ein Wissenschaftler notiert rückblickend, dass die Deklinationen der zu NGC 2029 und NGC 2030 gehörenden Einträge in Herschels Katalog vertauscht sind und so in den NGC übernommen wurden. Auch wird im NGC für NGC 2030 vermerkt: 1st of 3, wobei NGC 2032 und NGC 2035 die beiden weiteren Teile bilden, jeweils mit Positionsangaben nahe denen von NGC 2029.

Mit einer ähnlich der in NGC verzeichneten Positionsangabe ordnet Edward Charles Pickering NGC 2029 der Großen Magellanschen Wolke zu, beschreiben Harlow Shapley u. a., dass NGC 2029 und NGC 2032 Teile eines 20 Parsec durchmessenden Nebels sind, der durch einen dunklen Nebel von etwa 5 Parsec Breite und unregelmäßiger Gestalt unterteilt wird, und notiert Karl Gordon Henize NGC 2029 als ein Teilgebiet eines Hα-Emissionsnebels, den er mit N 59 bezeichnet und der in dem Bereich N59A die Objekte NGC 2032 und NGC 2035 umfasst. In gleicher Weise wird die Bezeichnung NGC 2029 in späteren Publikationen von weiteren Autoren verwendet; in der ESO/Uppsala survey wird darüber hinaus die alternative Bezeichnung ESO 056-EN 156 eingeführt.

8. NGC 2829 = mehrere Kandidaten
The position precesses to RA 09 19 42.2, Dec +33 39 47, but there is nothing there. (Refer to Bindon Stoney's sketch in following the rest of this discussion.) However, since the position of Stoney's "eF" galaxy is not specified very exactly, there are three candidates that are generally given some consideration. Based on the apparent position of the object in Stoney's sketch, the best fit to his diagram appears to be the star listed above, but PGC 26356 and PGC 2036350 are sometimes listed as NGC 2829, so they are discussed in the two entries immediately below, and although the star cannot be considered a certain identification, it is as certain as can be expected without having been present on the night Stoney made his sketch. Discovery Notes: Although Dreyer credits the discovery to William Parsons, 3rd Earl of Rosse, he notes that many of Rosse's nebular discoveries were actually made by one of his assistants, in this case George Stoney. Additional Discovery Notes: Stoney's observation of Mar 13, 1850 states "There are here 15 knots in all." His (brother's) sketch of Jan 8, 1851 is accompanied by the statement "A group of 3 neb. and others round them. Sketch made." Although the Historical Identification for this entry says that there is "nothing there" at the precessed position of Dreyer's NGC coordinates, the star listed above lies only an arcmin southwest of the position he estimated from Stoney's diagram, while the other candidates are considerably further from that position; and aside from the confusing inversion of the positions of the "3 neb.", Stoney's sketch shows the correct positions of all the other objects in the region, so although the identity of NGC 2829 might not normally be considered certain, it appears that the star listed above is by far the best candidate for the object in his sketch. (I consulted Corwin about this object, and he not only agrees with this analysis, but points out that the nebular candidates are so much fainter that Stoney probably couldn't have seen them at all.)

9. NGC 3167 = NGC 2789?(erledigtErledigt)
The position precesses to RA 10 14 36.8, Dec +29 35 45, but there is nothing there nor near there. The key to identifying the object (per Corwin) is d'Arrest's mention of a magnitude 11 star 9.5 seconds of time to the west, and very slightly north. This agrees with the region near NGC 2789, which has an 1860 RA exactly 1 hour smaller, suggesting a typographical error by d'Arrest in recording that coordinate. Using an 1860 RA of 09 06 37 the position precesses to RA 09 15 00.0, Dec +29 42 42, only an arcmin south of the galaxy listed above, and the aforementioned star makes the identification as a duplicate of NGC 2789 certain. Discovery Notes: Because of the large error in d'Arrest's position, NGC 3167 was thought to be a lost or nonexistent object into the early 21st century; as a result, LEDA has an entry ("PGC 5067762") for that "unknown" object, albeit with a designation that is not recognized by a search of the LEDA database. Physical Information: Given the duplicate entry, see NGC 2789 for anything else.

10. NGC 5632 = NGC 5691? (erledigtErledigt)
One of three objects (NGC 5632, 5651 and 5658) observed by Bond on the same night, previously thought to be stars; but in 2015 Steinicke showed that if Bond misidentified the star, all three objects were duplicate observations of other NGC objects. A later iteration of this page will discuss the matter in more detail; but for now, the corrected identification shown above will have to do.

11. NGC 5651 = NGC 5713? (erledigtErledigt)
One of three objects (NGC 5632, 5651 and 5658) observed by Bond on the same night, previously thought to be stars; but in 2015 Steinicke showed that if Bond misidentified the star, all three objects were duplicate observations of other NGC objects. A later iteration of this page will discuss the matter in more detail; but for now, the corrected identification shown above will have to do.

12. NGC 5658 = NGC 5719? (erledigtErledigt)
One of three objects (NGC 5632, 5651 and 5658) observed by Bond on the same night, previously thought to be stars; but in 2015 Steinicke showed that if Bond misidentified the star, all three objects were duplicate observations of other NGC objects. A later iteration of this page will discuss the matter in more detail; but for now, the corrected identification shown above will have to do.

13. NGC 7054 = NGC 7080? (erledigtErledigt)
Previously thought to be a lost or nonexistent object, but recently shown to be an observation of NGC 7080 with a misidentified comparison star; to be fleshed out when the Historical Identification is taken care of.

14. NGC 7210 = NGC 7487? umändern
The position precesses to RA 22 06 22.2, Dec +27 06 31, but there is nothing there nor anywhere near there, so until recently the object was thought to be lost or nonexistent. However, in April 2016 Corwin took a look at the record of Herschel's sweep, and found that Herschel made a one hour error in recording the right ascension (which was too small), and a one degree error in the NPD (which was too large). Correcting for that, the position becomes 1860 RA 22 59 58, NPD 62 34.3, which precesses to RA 23 06 44.2, Dec 28 11 03, about 1.4 arcmin west northwest of the galaxy listed above, the description fits, and there is nothing else nearby, so the identification is certain.

15. IC 400 = not found?
The position precesses to RA 05 03 43.9, Dec -15 46 00, but there is nothing there. This is hardly surprising, as Stone did not bother to measure the declination of his #209, only giving the position of his comparison star and an offset in right ascension, so the object he observed could be somewhat north or south of the IC position (hence Dreyer's guess-timated North Polar Distance). As it happens there are only two galaxies in the area, both only a couple of arcmin to the south. Looking at modern photographs, the more likely candidate would appear to be 6dFJ0503456-154909, a 16th-magnitude "spindle"; but if we take into account the realities of late 19th-century visual observations, the 17th-magnitude galaxy listed above is actually more likely to be IC 400, because the superimposed 15th-magnitude star, combined with its small apparent size, makes it a perfect fit to Stone's description as "16.0 magnitude, 0.1 arcmin", while the technically brighter but larger galaxy was probably too faint for him to see, since its light is spread out over a much larger area, and if seen, should have led to a larger estimate of the size. Given these circumstances it is hardly surprising that some references list PGC 905996 as IC 400, and others list the other galaxy (though usually with a warning about the considerable uncertainty of the identification, in either case); so even though the spindle is less likely to be IC 400, it is discussed immediately below.

16. IC 554 = IC 555?
The position precesses to RA 09 41 47.9, Dec +12 26 01 (whence the position above), but there is nothing there. It is generally assumed that Swift actually observed Javelle's IC 555, and simply made an error of 10 arcmin in its declination. However, aside from the fact that this would still put Swift's position well to the southwest of IC 555, the descriptions of the two objects are completely different. So it seems far more likely that Swift observed a different, fainter galaxy (in which case he would still have had to make a large error in its position), or mistook a faint stellar object for a nebula (which, given his description of the object seems by far the most likely, but since there are no obvious stellar matches near his position, is still not at all certain). Which if any of the possibilities might be correct is a mystery, as there is no reasonable alteration of Swift's position that fits any of them; so the best description of IC 554 appears to be, as noted above, "lost or nonexistent".

Weblinks