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RA: 07h 29m 10.7669s
Dec: +20° 54′ 42.488″
Ch: MSA:176, U2:139, SA:5
Type: planetary nebula
Mag: B=10.28, V=10.11
Select a sketch and click the button to view
Select a photo and click the button to view
Synonyms: H IV-045
Discovered in 1787 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "a star 9th mag with a pB milky nebulosity, equally dispersed all around. A very remarkable phaenomenon." In the Philosophical Transactions, 1791, Herschel wrote: "A star with a pretty strong milky nebulosity, equally dispersed all around; the star is of about the 9th magnitude. A memorandum to the observation says, that, having just begun, I suspected the glass to be covered with damp, or the eye out of order; but yet a star of the 10th or 11th magnitude, just north of it, was free from the same appearance. A second observation calls it one of the most remarkable pheanomena I ever have seen, and like my northern planetary nebula in its growing state."
Sketched and described: "On the Planetary Nebula 45 H IV. Geminorum" [1868MNRAS..28..154K].
Lassell, W. (1854) Observations of the nebula of Orion, made at Valletta, with the twenty-foot equatorial. Memoirs R.A.S., 23, 53-62.
Sketched and described.
In the 5th edition of Webb's Celestial Objects for Common Telescopes it is described as "Herschel observed this object as a 9th mag star 'with a pretty bright nebulosity, equally dispersed all round; a very remarkable phenomenon.' John Herschel describes it as an 8th mag star, 'exactly in centre' (not exactly, E. of Rosse, d'Arrest) 'of an exact;y round bright atmosphere, 25 arcseconds in diameter.' Smyth, who rates it 7.5 mag, says he 'could only bring it to bear as a burred star.' I was so much surprised at the result in my inferior telescope, that I cannot help supposing some temporary impediment to distinct vision at Bedford, for on coming accidentally across it in 1850, I found such a conspicuous nebulosity that I though it was either damp on the eye lens or a telescopic comet; and in 1852 I entered it as a 'bluish nebulosity, quite like a telescopic comet.' 1865, with 5.5-inch, I perceived a very faint trace of a brighter border south, a little following. The E. of Rosse saw a marvellous object - a star surrounded by a small circular neb, in which, close to the star, is a little black spot. This neb. is encompassed, first by a dark then by a luminous ring, very bright, and always flickering; perhaps a spiral. Buffham sees the dark ring with 9-inch reflector. Key's 18-inch mirror showed two concentric bright rings and the dark spot, 1868. A mass of luminous fas. It lies 2 degrees S.f. Delta Gem."
Burnham, S. W. () "Measures of planetary nebulae with the 36-inch equatorial of the Lick Observatory", Pub. Lick Obs., vol 2, p159-167. "One of the most beautiful objects of the kind in the heavens. The central star is round and sharp with all powers. A measure of the diameter of the bright inner disc in the direction of the outside comparison star gave 19'' and for the diameter of the whole disc in the same direction 44.7''. Lassell speaks of the comparison star as being nebulous. I did not notice any peculiarity in the appearance of this star."
Journal BAA, 35, p159
Planetary, with 9.5mag central star, surrounded by bright irr.elliptical ring 19''x15''; about 8'' outside of this ring are found broken patches of an outer ring and fainter matter forms an oval disc 47''x43''.
Doig, P. (1925) Notes on the nebulae and clusters in Webb's 'Celestial Objects for Common Telescopes' (Sixth edition, Vol.ii). Part II. M.N.R.A.S., 35(8), 280.
Sanford calls it an "outstanding object .. the Eskimo, or Clown Face, Nebula. It is a bright disk about 40 arcseconds in diameter near a 9th mag star. Even a small telescope (under 6-inch) will show it as a small greenish ball with slightly fuzzy edges. An 8-inch will begin to show that the disc is surrounded by another ring or shell, which becomes conspicuous in a 16-inch. This is the fur parka around the Eskimo's face. The central star, which is easy to see at 9th mag, is sometimes identified with the Eskimo's nose. Detail within the inner disk is complicated and made difficult to see by the presence of the central star."
Hoey, M. () "The Morphology of Planetary Nebulae - The Eskimo Nebula", IAJ, Vol 18, 227-229.
"Abstract: Some new measurements on the Eskimo nebula, NGC 2392, are discussed in the context of a general review of the morphology of Planetary Nebulae."
"... Planteray nebula with multiple shells are particularly interesting from a morphological viewpoint and some have been analysed to eluciadte a plausible structure. An example of such a nebula is the double shell planatary NGC 2392, the Eskimo..." [not much else; some theoretical speculation]
Terzian Y (1980) Q.J. R.astr.Soc vol 21, p82-92 [09.16.1] notes that this planetary shows multiple shell structure.
The RNGC (Sulentic and Tifft 1973) notes that this is a planetary nebula.
Photo Index by Jim Lucyk: Sky&Tel. 10/69 p229, Astronomy mag. 1/78 p45, Astronomy mag. 2/84 p78, Astronomy mag. 9/74 p23, Astronomy mag. 10/86 p40, Deep Sky #13 Wi85 p12, Deep Sky #21 Wi87 p26, Deep Sky #6 Sp84 p14, Deep Sky #17 Wi86 p26, Burnhams V2 p941, Sky&Tel. 2/60 p217.
Ken Reeves, in "SACNEWS On-line for February 1997", observing with a 10-inch f/4.5 scope, notes: NGC 2392 (07 29.2 +20 55) This planetary nebula is commonly known as the Eskimo Nebula. At 70x, this is a small object (although large for a planetary), pretty bright with a star to the W which is a little brighter, much brighter in the middle with the central star obvious. Both averted vision and the UHC filter makes it grow quite a bit. I noticed a slight blue color to it. At 170x, I saw a bright center, a dark ring surrounding the middle, then a bright ring around that. In Burnham's Celestial Handbook (by Robert Burnham Jr), he states "To the author of this book, the whole nebula irresistibly suggests the classic and unforgettable features of W. C. Fields." Looking at the pictures in his book, I have to agree with him.
Houston calls it "one of the easiest planetaries in Gemini. I have seen its 9.7 mag 50 arcseconds disk with the four-inch Clark stopped down to 2 inches. There are even reports of it being glimpsed in binoculars, but it would be indistinguishable from a faint star. . . . Although NGC 2392 can be seen in small instruments, it becomes a truly exciting object in larger ones. Ronald Morales, using his 10-inch f/5 reflector in the Arizona desert reports that the nebulosity surrounding the 'easily seen central star' resembled a 'great blue snowball.' "
(PK197+17.1) Mag=9.2. Clown or Eskimo Nebula: very well known planetary in Gemini: 7h 29.2; +20° 55' This object of more than 40" diameter is so well known that it does not require an extensive description, other than to add that the uneven halo around the bright center is easy to spot in a small telescope. In an 8" scope, the outer shell does not break up into the bright clumps seen in a large instrument, but rather has a faintly mottled, uneven appearance. We observed it last in a broad patch of zodiacal light before dawn that had 'wiped out' the faint stars of the region: yet, the planetary was clear and bright.
Houston notes: "When I stopped my 4-inch refractor down to two inches, NGC 2392 appeared stellar,with only a mere trace of a fuzzy edge. But will full aperture it was clearly a planetary. To do this object justice and to see the slight mottling of its disk, I needed a 10-inch reflector and crystal-clear skies." He has seen the central star with 150 power.
Hartung notes: "a fine bright pale blue nebula with very clear central star 9th mag in a good contrasting field . . it is about 30 arcsec across."
Listed by the Herschel Club, described as "very small and circular, bluish tint in colour, above a field star, opaque disk, very pretty. 6-inch, 48x."
Mullaney calls this a "bright blue planetary in Gemini .. measuring 44 arcseconds by 13 arcseconds .. shines at magnitude 8.9 with an obvious 10th mag central star. It reminds some observers of a star seen through a dewed-over eyepiece. It's easy to pick up in 3- and 4-inch telescopes, while dark structures are visible in 10- and 12-inch apertures."
Tom Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "9.7M; >1' diameter; 11M center star; N-filter shows some structure; a.k.a. "CLOWN FACE"; 40' SSE of bright star (5M 63 GEM)."
Steve Coe, observing with a 13" f/5.6, notes: "Pretty bright, large and round, with obvious central star at 100X. At 240X two rings surround the star and several dark markings appear. This object has been light green in every telescope I have ever owned. In the 13" it takes a great night, but the features which make up the "face" of the Eskimo Nebula can be seen."
Observer: Steve Coe; Your skills: Advanced (many years); Date/time of observation: 24 Apr 1998; Location of site: Sentinel Arizona (Lat +33, Elev 1500 ft); Site classification: Rural; Sky darkness: 7 1-10 Scale (10 best); Seeing: 7 1-10 Seeing Scale (10 best); Moon presence: None - moon not in sky; Instrument: 13" f/5.6 Newtonian; Magnification: 100X, 440X; Filter(s): ; Object(s): NGC 2392 or the Eskimo Nebula; Category: Planetary nebula.; Class:
Description: At 100X this famous planetary is bright, pretty large, round and has a bright, stellar nucleus. Even at low power this is a lovely light aqua disk with an obvious central star. The difference between direct and averted vision is almost startling. Direct viewing shows almost just the star and averted vision makes the disk jump out of the eyepiece. There is a bright star to the north and a fainter one to the northwest. Using the 4.7mm Meade UWA eyepiece is a great view. The central star is still obvious and stands out from the nebula very nicely. The disk is big at this magnification and several dark, curved markings show the "face" of the Eskimo. There is a noticeably brighter inner disk and a much fainter outer area. This is an excellent view of this lovely object.
Donald J. Ware:"The Eskimo Nebula. This is another fine planetary nebula. It has a bright central star which is surrounded by a halo of nebulosity about 40" in diameter. The halo is brightest close to the star, and fades out further away. Mottling and a lacy texture can be seen in this very pretty object."
Observer: Lew Gramer; Your skills: Intermediate (some years); Date/time of observation: 1998-03-10/11 01:15 UT; Location of site: Medford, MA, USA (Lat 42oN, Elev 5m); Site classification: Suburban; Sky darkness: 5.1 Limiting magnitude; Seeing: 5 1-10 Seeing Scale (10 best); Moon presence: None - moon not in sky; Instrument: 8" f/10 SCT on fork; Magnification: 90x, 170x, 340x; Filter(s): None, UHC; Object(s): NGC 2392 (Eskimo Nebula)
A quick finder sweep E from delta Gem, to a pretty NE-SW line of mag. 6 stars, with the lovely tight trio 63 Gem at its center. The famed planetary is at the invisible E vertex of an equilateral triangle with 63 and southerly 61 Gem. In the eyepiece at 90x, the Eskimo is a bluish-gray "dot" just S of a mag. 9 star. Clearly non-stellar even at this low power, little detail can be seen in the bright, small face of the nebula. However, the subtle hints of its outer halo showed up best against the light polluted sky at this power. At 170x, a dark arc suddenly becomes apparent in the core disc, beginning N of the obvious central star and sweeping W. At 340x, this arc began to appear complex, and a further brightening to the S was also noted. Finally with UHC at 340x, all the dark details stood out well, beginning to show hints of fine-grained complex mottling along their edges, and small areas of the faint outer halo suddenly became visible again, especially SE - though again less clearly than at 90x. --
Observer: Todd Gross; Your skill: Intermediate ; Date and UT of observation: 10/24/97 0755 GMT; Location & latitude: 22 miles west of Boston, Ma. 42.3N; Site classification: Suburban; Limiting magnitude (visual): 4 (estimated)4 (est) in vicinity of object; Seeing (1 to 10 - worst-best): 3; Moon up (phase?): Yes, 40%; Weather: Partly cloudy (high veil of cirrus clouds); Instrument: 16" Newtonian-dob w. 96/99% coatings f/4.59; Magnifications: 70x, 143x, 250x, 310x; Filters used: UHC; Object: NGC 2392 (Eskimo nebula); Constellation: Gemini vicinity; Object data: Planetary Neb.
Seeing was poor, and there was a high veil of clouds. Although I did not see the double envelope structure, the planetary nebula The Eskimo Nebula, was very interesting because of the difference between the view with the UHC filter, and without.
At low power this tiny fuzzball had a blue-green color, less obvious as magnification increased. With high magnification the fuzzball looks like an unresolved, but very bright, tiny, globular cluster, completely and symettrically round, with a very noticeable brightening in the center. HOWEVER, with NO UHC filter, it appears as a roughly evenly illuminate circle of nebulosity, with a perfectly centered, and easy to see central star.
Observer: Mark G.Birkmann Your skills: Intermediate (some years) Date/time of observation: 11-11-99, 8:50 UT, (2:50 am CST) Location of site: New Haven, Missouri (Lat ~38, Elev ~700') Site classification: Rural Sky darkness: 6 1-10 Scale (10 best) Seeing: 5 1-10 Seeing Scale (10 best) Moon presence: None - moon not in sky Instrument: 40" f/5 dob Magnification: lowest power 125x Filter(s): OIII, H-beta, Orion Ultrablock Object(s): NGC 2392, Eskimo Nebula Category: Planetary nebula. Class: 3B + 3B Constellation: Gemini Data: mag 9.9(P) size 19.5" Position: RA 07:29m 10.8s DEC +20:54' 43" Description: This beautiful pn showed a bright inner ring surrounding the central star. The area inside the ring was evenly illuminated and slightly darker than the outer halo. The lower part of the ring split for a short distance with a dark area in the separation equal in brightness to the nebulousity inside the main ring. The outer halo was about 3x the diameter of the inner ring. It was evenly illuminated except for a bright area near the top and a slightly brighter area on the right side. I have seen so many photos of this object that the upper bright area may have been coming from my memory rather than from my retina. This doesn't explain the bright area on the right though, since none of the photos I've seen show this to be a particularly bright area. A drawing can be seen at http://www.fortunecity.com/greenfield/twyford/637/drawings.htm
Observer: Yann POTHIER (France) Your skill: advanced (many years) Object: NGC 2392 (PK 197+17.1; PN G197.8+17.3; ARO 24; clown nebula) Category: planetary nebula Constellation: GEM Object data: Vmag=9.1; Bmag=9.9; 47x43"; type IIIb+III; central star HD 59088 of Vmag=10.5 (Bmag=9.1); discovered by Herschel in 1786 (as a PN by Lassell in 1853); ELCAT: [OIII, 496+501nm] = 16 x [Hbeta, 486nm]. RA/DE: 07h29.16m, +20°54.8' (2000.0) Date and UT of observation: 26 December 1994, 23h30UT Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36) Site classification: rural, alt.1650m (5500ft) Limiting magnitude (visual in UMi): 6.31 with indirect vision 25% of the time Transparency (1 to 5 - best to worst): 1 Seeing (1 to 5 - best to worst): 4 Moon up (phase?): no Instrument: Coulter 445mm/17.5" F/4.5 Magnification: 45-312x Filters used: OIII, UHC
Description: at 312x, medium sized PN (large with filter), bright and round; about 47" in diam. without filter and 64" with OIII (estimated on drawing) because of a weaker external corona seen at 312x and OIII; a brighter central area is seen, a little oval, about 30"x25" N-S; UHC provides a good contrast gain and erases the central star, OIII gives a very good contrast gain and the extended edges are getting sharper; the nebula looks bluish at 45x; the mag8.5 star is at 1.6'N from the central star.
Observer: Yann POTHIER (France) Your skill: advanced (many years) Object: NGC 2392 (PK 197+17.1; PN G197.8+17.3; ARO 24; clown nebula) Category: planetary nebula Constellation: GEM Object data: Vmag=9.1; Bmag=9.9; 47x43"; type IIIb+III; central star HD 59088 of Vmag=10.5 (Bmag=9.1); discovered by Herschel in 1786 (as a PN by Lassell in 1853); ELCAT: [OIII, 496+501nm] = 16 x [Hbeta, 486nm]. RA/DE: 07h29.16m, +20°54.8' (2000.0) Date and UT of observation: 28 December 1991, 03h30TU Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36) Site classification: rural, alt.1650m (5500ft) Limiting magnitude (visual in UMi): 6.31 with indirect vision 25% of the time Transparency (1 to 5 - best to worst): 2 Seeing (1 to 5 - best to worst): 3 Moon up (phase?): no Instrument: Japanese Newtonian 4.25" (114mm), F/7.8 Magnification: 72-150x Filters used: prism
Description: visible at 36x as a fuzzy star, making a nice couple with a mag8 star 5' to the N; at 72x, always easier to detect this planetary when star-hopping with this power; larger with a quite obvious central star embedded in a nebulous halo, brighter to the center; at 150x, quite homogeneous, large and perfectly round, estimated to be about 40".
Observer: Yann POTHIER (France) Your skill: advanced (many years) Object: NGC 2392 (PK 197+17.1; PN G197.8+17.3; ARO 24; clown nebula) Category: planetary nebula Constellation: GEM Object data: Vmag=9.1; Bmag=9.9; 47x43"; type IIIb+III; central star HD 59088 of Vmag=10.5 (Bmag=9.1); discovered by Herschel in 1786 (as a PN by Lassell in 1853); ELCAT: [OIII, 496+501nm] = 16 x [Hbeta, 486nm]. RA/DE: 07h29.16m, +20°54.8' (2000.0) Date and UT of observation: 28 December 1991, 03h30TU Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36) Site classification: rural, alt.1650m (5500ft) Limiting magnitude (visual in UMi): 6.31 with indirect vision 25% of the time Transparency (1 to 5 - best to worst): 2 Seeing (1 to 5 - best to worst): 3 Moon up (phase?): no Instrument: Meade SCT 8" (203mm), F/10 Magnification: 87-145x Filters used: -
Description: at 45x, just visible as a nebulous star, easy and bright PN; at 87x, obvious central star, mag9 star 1.7' to the N; at 145x, large nebula, gradually merging with the background sky; at 290x, a mag13 star is forming a triangle with N2392 and the mag9 star, the nebula is larger but still homogeneous.
POSS: 1'.65 due S of m8 *. M+3-19-19 (mz=14.6) at 19'.2 in pa193.
6cm - easily discernable @ 22x just S of m9.5 *. a bit fntr than this * and
7cm - not real consp in rich 2deg fld @ 30x, although readily discernable from
a *. 110x best in showoing cen *, which is steady w/averted vis. diam of
neb 1/4-1/3 distance to m8 * N. BS, 15Apr1993, Anderson Mesa.
15cm - at lox the cen * is vapparent w/neb seen w/averted vis. at higher
powers (67x/134x) the shell becomes more interesting w/dk patch just
preceding the cen *. located 3' N of m8 *. bluish. HM/BS, 19Jan1971,
- br hisfcbr pn w/br `blinking' cen *. sl oval, elong ~N-S @ 195x. UHC
brings out shelf-like core around cen *, which seems to have tiny dk
area around it. core also elong sl N-S. halo smooth, pretty sharply
defined. Zw gx to S not obvious @ 140x. BS, 4Feb1991, Anderson Mesa.
25cm - vbr. at lox blinking effect is seen. at 305x vbr cen * obvious. neb
seems patterned w/tightly intertwined coils. circ; granular; great
30cm - 149x: br bluish globe w/cen * easy. 238x: perhaps sl unevenly br w/dk
ring 1/2way out, partic to E. cen * in sm 15" br area. overall diam 45";
[amastro] posting, Sat Nov 25, 2006
82" telescope, McDonald Observatory near Fort Davis, Texas, USA
f/13.7, 35mm Televue Panoptic (5' fov, 812x)
The Eskimo was bright, a little elongated, and was another disk- within-a-disk object. The outside of the inner disk was oval with one end flattened and was distinctly ropey, showing lots of fine detail. The outer shell was much more amorphous and showed very little detail. Both shells were aqua in color, with the inner shell having a stronger hue. In retrospect this object looked a lot like NGC 1535, only larger. If it weren't for the long line of observers behind me I could have looked a this guy for a long time.
Located this nebula easily in moonlight with a 10-inch f/5 at 30x. Appears round, diffuse, globular-like glow. At 120x it looks very much like a globular cluster; the outer edges are very fluffy, growing gradually brighter to the middle, where it seems to gather not to a point but rather to a disc. No particular colour was noted.
Alldays (22.50S, 20.12E, 770m).
12-inch f/10 SCT (76x, 218x, 346x)
Very faint, medium large, smudge right next to a 8.2 whitish star which is just about 2' to the north of this nebula. The nebula show dark shades and do resembles two eyes looking at you. No sharp edges, and a very poor star field. I noticed a hint of an outer envelope or fringe around the core, which look the furs on the eskimo's hat, amazing.
Instrument:12-inch Dobsonian Reflector Telescope.
Sky Conditions:Dark moon and stars magnitude 6 and fainter are barely visible with the naked eye.
Transparency of the Sky:The most clear sky possible.
Seeing:Excellent clean sky,limited star flickering and brilliant objects.
Object Type:Planetary Nebula.
First Impression:This object looks like a large out of focus star.
Chart Number:No.3(Extract taken out of "Atlas of the Night Sky").
Size:9mm Eyepiece:Field Of View:15'/8=1.8'.
7mm Eyepiece:Field Of View:15'/7.5=2'.
Size in Arc Minutes:1.9'.
Planetary Nebula is 1.9'*0.9'.
Brightness Profile:Towards the central outskirts of this planetary nebula it grows brighter.
Challenge Rating:Glorious Sight.
This planetary nebula is slightly oval and well defined.By observing this planetary nebula it looks like this object has the face of a clown.This planetary nebula has a bluish-green surface.
Observing site: Little Tycho Observatory
[7h 29m 12s, 20° 55m 0s] A very hazy star in tonight's moon washed sky. Brighter towards the center, I could see no ring.
Observing site: Little Tycho Observatory
[7h 29m 12s, 20° 55m 0s] A medium sized, bright planetary nebula. I was able to make it "blink". Very nice!
Observing site: Little Bennett Regional Park
[7h 29m 12s, 20° 55m 0s] In the 24mm, it looks like a very fuzzy star. In the 9mm, the central star is plainly seen in slightly averted vision, in the fovea, it's just a faint patch. The mottling that gives the planetary it's name is invisible.
The Messier objects
The Bennett objects
The Caldwell list
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