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Type: planetary nebula
Mag: B=17.9, V=?
Discovered by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. His discovery entry, taken during Sweep No. 769 reads: "An object whose nature I cannot make out. It is certainly not a star, nor a close double star; but it is not round, and I should call it an oblong planetary nebula, by reason of its decidedly marked though somewhat dim outline, were there not some suspicion of its being double, as if a very close and highly condensed double nebula. It is very small and rather faint, 8 arcseconds long, 5 arcseconds broad, and equals a star of 10th mag. In a field with at least 60 or 80 stars, all sharp and well defined but this. (N.B. The PD open to uncertainty, as the telescope rests on the gallery, and I cannot get it low enough for bisection.)" His second observation was recorded as "Planetary nebula. In a field with, and south of a cluster, and on a rich ground is the undefined object of Sweep 769. It is no doubt a very faint, small, round planetary nebula, 4 arcseconds, or, at the very utmost, 5 arcseconds diameter and = in light to a star 11th mag. There is an appearance of elongation, but this is probably owing to one or more extremely extremely small stars, as the field is full of such. All the other stars are sharp, and the definition to-night is perfectly good."
The NGC records it as "planetary nebula, faint, small, slightly extended and lies amongst 60 stars." Dreyer quotes Burnham in the Notes to the NGC as commenting: "Not planetary, but bi-nuclear"
Burnham, S. W. () "Measures of planetary nebulae with the 36-inch equatorial of the Lick Observatory", Pub. Lick Obs., vol 2, p159-167. "Not planetary. There are two nuclei giving it a sort of dumb bell appearance."
"Two pB E nuclei in F, S, R, well-defined nebula."
Chopinet, M. & Lortet-Zuckermann, M.C. (1972) A note to designations of planetary nebulae. Astron.Astrophys., 18, 166-167.
NGC 2452: He 2-4, PK 243-1°1, RCW-17
The RNGC (Sulentic and Tifft 1973) notes that this is a 12.5 mag planetary nebula.
Photo Index by Jim Lucyk: Sky&Tel. 4/70 p221, Deep Sky #17 Wi86 p11.
Steve Coe, in SACNEWS On-Line for February 1996, writes: "NGC 2452 is bright, pretty large, bright middle, round at 270X. This planetary nebula was immediately recognized as non-stellar at 135X. The central bright section was never stellar at any power on a night I rated as 7 out of 10 for seeing. The nebula was a light green color. It is located on the south side of the open cluster NGC 2453. So, there are two places in Puppis where you can see a cluster with a planetary nebula at the edge. The more famous is M-46 with NGC 2438, now try the copy-cat version; cluster NGC 2453 with NGC 2452 at its edge."
Steve Coe, observing with a 13" f/5.6, notes: "Bright, pretty large, bright middle, round at 270X. This planetary was immediately recognized as non-stellar at 135X. The central bright section was never stellar at any power. The nebula was a light green color. It is located on the south side of the open cluster NGC 2453."
AJ Crayon, using an 8" f/6 Newtonian, notes: "is another planetary nebula. It is 20"x10" 12m, in position angle north, has a star at its north edge and is with NGC 2452 10' north, at 100X. This nebula is best seen with a UHC filter, a dark hood and averted vision while waiting for moments of good seeing."
16-inch f/10 SCT (127x, 290x)
This is a tight cluster with various magnitude stars. Somehow flare out to the northern side. The faint grey glow of the planetary is easy seen to the south of the grouping.
The Messier objects
The Bennett objects
The Caldwell list
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