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RA: 13h 57m 44s
Dec: −39° 58′ 42″
Ch: MSA:932, U2:403, SA:21
Ref: SIMBAD, NGC/IC
Type: reflection nebula
Mag: B=?, V=?
Size: 13′ x 8′
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Discovered by John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "a close double star in a very large, bright, luminous atmosphere, 2' diameter. The star A which is quite as bright, has no such atmosphere. The atmosphere is very little brighter in the middle. The star was not noticed as double till too late for a good measure after I showed the object to my attendant J.S., verified with 240x and 320x. A furious hot north wind, but the definition of stars excellent. It is no illusion, other stars are sharp and brilliant, and have not the least nebulous appearance." The next time he observed it, he showed it to Mr Maclear and a friend, calling it a "double star h 4636 involved in nebulosity." The next observation was accompanied by a sketch of the object and comments about surrounding field stars, and "the nebulosity is very evident ... neb at least 2' or 2.5' diameter." His final observation recorded it as "very faint, 2' diameter, and star of 9th mag following, is about 4' distant, is unaffected with nebulosity." In his notes to the sketches, he wrote: "[NGC 5367 and NGC 1847] are nebulae, centrally involving double stars. Central superposition must undoubtedly be held strong presumptive evidence of physical connexion."
The NGC records it as "a remarkable object, very bright, very large, very suddenly much brighter in the middle to a double star."
"Extract of a letter from Sir John Hershel to Francis Baily, Esq., dated Cape of Good Hope, October 22, 1834", Monthly Notes RAS, 3, 75-77.
"... A brief recapitulation of a few of the more interesting objects and remarks which have fallen under my notice may not be unpleasing to you. ... On the 26th of June I observed an extremely remarkable object of the class of close double stars, centrally involved in a nebulous atmosphere. Its place is in RA 13h 47m 30s NPD 129° 9'. The diameter of the nebula is about 2' and the stars are equal, each of them 9-10 mag., distance about 1.5 or 2 arcsec. The nebula is nearly uniform, or, at least, very little condensed about the star."
Table IV: B * magn 8, inv in neb.
B structureless nebulosity round CPD -39°6131 (h4636). Neighbouring stars are now in very different positions from those figured by Herschel (CGH VI 10)
(Sulentic and Tifft 1973) notes that this is a diffuse nebula.
The nebulosity was included in the Catalogue of Bright Nebulosities in Opaque Dust Clouds by Bernes as No. 147. He describes it as a reflection nebula 4' x 3' (measured north-south by east-west), appearing very bright on the blue plate. He notes that the nebulosity is located on the edge of the cometary globular CG 12, which measures 20'x8'.
Burnham calls this a 10th mag nebula in Centaurus, 1.3' x 1', large, bright, slightly elongated and has a double nucleus.
= Bernes 147, N5367, GN 13.54.7
Class: C (reflection neb)
Comments: double star
Tom Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "10M; 1.3' x 1' extent; double nucleus; includes embedded cluster I.4347."
Hartung writes: "This curious object is a round rather faint haze about 2' across surrounding a small pair (10.0 & 10.7, 4 arcsec, 33 ) and brightening it." Sanford calls it "a small, 10th mag nebula, which may be of the bipolar dust-type - light illuminates the nebula in two opposite directions."
WDS: pair = h4636 = CoD-39 8581: V=10.26/0.20 (Srn) and V=10.70/0.51 (Nrn).
who-sis: * S = CoD-39 8583: V=10.08/0.13. * N V=13.30/0.50; * NE V=12.77/0.84. last two *s w/in 2' radius of neb.
15cm - mod f refl neb mostly around Wrn of two m9 *s; a m9 * S also has wk neb.
140x: 3' diam around main *, centered SW of *. filters no help. extends at least to m12 *s N & NE. approx circ around each *. BS, 3Mar1990, LCO.
12-inch f/10 SCT (95x, 218x, 346x)
The nebula is quite bright with a faint double star embedded in the nebulosity. It is not quite round but extends more in haziness to the NE, with the SW part slightly larger and boxy in shape. More or less 5' SE a bright spot of haze can be seen surrounding a faint star most probably GN 13.549.
Instrument:12-inch Dobsonian Reflector Telescope.
Sky Conditions:Whole Milky Way is visible.
Transparency of the Sky:The sky is clean.
Seeing:Atmosphere stable with little interference.
Limiting Magnitude:Magnitude 6.
First Impression:This object looks like a small cloud of gas and dust.
Chart Number:No.17(Extract taken out of "Atlas of the Night Sky").
Size:26mm Super Wide Field Eyepiece:Field Of View:57'/15=3.8'.
20mm Ultra Wide Angle Eyepiece:Field Of View:50'/14=3.5'.
Size in Arc Minutes:3.6'.
Nebula is 3.6'*1.8'.
Brightness Profile:Towards the far outskirts of this nebula this cloud of gas gently grows slightly brighter.
Challenge Rating:Very Difficult.
This elusive nebula is observed as a faint reflection nebula illuminated by a bright star.There is some dark patches around this nebula.
The Messier objects
The Bennett objects
The Caldwell list
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