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RA: 15h 47m 41.55s
Dec: −61° 13′ 6.3″
Con: Triangulum Australe
Ch: MSA:983, U2:453, SA:25
Type: planetary nebula
Mag: B=?, V=?
Discovered by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "planetary nebula, not bright, pF, S, R, with something like a protruberance, which may arise from an accidental star, on or close to the edge. Not quite sharp; a little furred; light not quite uniform; an odd sort of mottling like a resolvable light; taken at first for a vF double star out of focus; 12 arcseconds diameter, but seen with x240; x320 is too high a power for it. See figure 7, Plate VI." On a second occassion he wrote "planetary nebula, seen, and a diagram of the adjacent stars made, but the stars are too dreadfully ill defined to-night to state any particulars further than that it is decidedly not a star, but has a disc approx 8 arcseconds diameter." His third observation was recorded as "planetary nebula, round, r arcseconds diameter, about equal in light to a 9th mag star; of a feeble intensity of light, nearly equable; under 320 it is not nebulous, but indistinct at the edges; a very singular kind of appearance - not 'mottled', not 'curdled', but yet not planetary. In a field with about 100 to 150 stars."
Sanford calls this a "small round planetary nebula, almost stellar in appearance (8 arcseconds in diameter), and at mag 13 rather faint in an 8-inch telescope."
The RNGC (Sulentic and Tifft 1973) notes that this is a planetary nebula.
Table IV: Not seen.
From: "Neat Southern Planetaries - IV."
NGC 5979 (PK 322 5.1/ SA2 124/ WRAY 16 187 / He2 135) (15477 6123) TrA is found near the southern boarder of Norma and the northern boarder of Triangulum Australe. This relatively bright planetary is contained in a starry field, having a photographic magnitude of 11.8 and a catalogued diameter of 8.0"sec.arc. The size is in fact more like 15"sec.arc., as David Frew states in AOST2. Visual magnitude of NGC 5979 is often stated as 13th in some references (like 13.01 in Sky Catalogue 2000.0) but it is likely 0.5 to 0.8 magnitudes higher.
In AOST2, the planetary is said to be faintly seen in the prism image in a 7.5 cm. I question this, because even in an O III filter, I frankly could not see it. (Derived by an aperture reduction filter placed over the C 8.) A 10.5cm. can probably distinguish it from the starry field but an O-III would be a help. In the C 8, the planetary looked slightly mottled, with the edges very even and smooth. I could see no colour in this object, though a larger Dobsonian may see a hint of a blue. Its appearance is slightly elliptical, along PA 90O ie. East West.
PNN is magnitude 15.3 and is invisible except for the largest Dobsonians. It has a mean radial velocity of +23 kms 1 indicating that NGC 5979 is moving towards the Earth. The distant has been listed as 3 300 parsecs, but based on the metallic emissions one recent reference states it is nearer to 3 600 parsecs. Again, little information is available though it is better covered than its cousin NGC 5844. The STScI derived image of this object can be seen in Figure 3.
The Surrounding Field of NGC 5979.
Gerd Bahr-Vollrath (Noosa Heads, Queensland, Australia) observing with an 8-inch f/12 SCT, writes in the The Webb Society Nebulae and Clusters Section Report No. 10, July 1992: "Fairly large and faint. A broad evenly illuminated ring is filled with fainter nebulosity."
15cm - mod br neb @ 80x, m10.0. strong [OIII], mod-strong UHC enhancements.
195x: 20" diam, circ, wkly annular. brtr area NE side. BS, 24Feb1990,
1995-05-28: 11x80.Technopark. 20:15 SAST. Hazy sky, thin clouds. Can see stars in the field of about 9.5 mag; the nebula can not be seen.
12-inch f/10 SCT (95x 218x 346x)
A faint, small planetary nebula that is rather difficult to detect. By no means star-like but rather a dense fussy dot. Higher magnification brings to the fore a hazy edge on this very round object. The planetary nebula displays a slightly grey colour. A faint string of stars runs out for almost 4’ towards the south-east in the field of view.
RA: 15h47m41s - DEC: -61o13'04" - Magnitude: 13 - Size: 0.10"
Tel: 12" S/C – 218x – 346x - Date: 16 September 2009 – Seeing 5.7
In this very busy star field it was not easy to see the faint out of focus spot. Add the UHC and 0111 filters help me to define the planetary as a frosted blue very round out of focus point amongst the faint stars.
RA: 15h47m42s - DEC: -61o13' - Magnitude: 11.5 - Size: 18"
Tel: 12" S/C – 218x - 346x - Date: 14 June 2009 – Vis: 5.6
Typical planetary, NGC 5979 is a faint out of focus round glow shines in an unmistaken blue/grey colour. The planetary given an intense light output. Higher power reveals a soft hazy edge somewhat smoky.
16-inch f/10 SCT (290x, 462x)
Very faint, small with a brighter middle. It seems to me that there is a flikkering of the middle star with care. The west show of a handful of faint stars in a arrow shape. Again some more faint stars spray out towards the SE.
Instrument:12"Dobsonian Reflector Telescope.
Sky Conditions:The fainter parts of the Milky Way are barely visible.
Transparency of the Sky:Haziness only visible on the horizon.
Seeing:Atmosphere stable with little interference.
First Impression:Planetary Nebula.
Chart Number:No.20(Extract taken out of "Atlas of the Night Sky").
Brightness Profile:High Surface Brightness.
Challenge Rating:Difficult to observe at low power,higher power is required.
Overall Shape:Oval,and well defined as a hazy disk in my 7mm ultra wide angle eyepiece at 214*.
Is a disk seen? Yes,a small oval disk is seen.
Is the edge sharply defined? Yes,it appears as an out of focus star.
What colour is the nebula? Green.
Is there a central star? No.
The Messier objects
The Bennett objects
The Caldwell list
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