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RA: 10h 24m 46.107s
Dec: −18° 38′ 32.64″
Ch: MSA:851, U2:325, SA:20
Ref: SIMBAD, Corwin (2004)
Type: planetary nebula
Mag: B=10.3, V=7
Select a sketch and click the button to view
Select a photo and click the button to view
Synonyms: H IV-027
It was discovered by William Herschel on February 7, 1785 with his newly completed 18.7-inch f/13 speculum telescope. He called it "a beautiful, very brilliant globe of light; a little hazy on the edges, but the haziness goes off very suddenly, so as not to exceed the 20th part of the diameter, which I suppose to be from 30 to 40 arcseconds. It is round, or perhaps a very little elliptical, and all over of an uniform brightness: I suppose the intensity of its light to be equal to that of a star of the 9th magnitude." and also as "Beautiful, brilliant, planetary disk, ill defined, but uniformly bright, the light of the colour of Jupiter. 40 arcseconds diameter. Second observation, near 1' diameter by estimation."
Observed by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "a very fine, large, planetary nebula, 25 arcseconds in diameter; a little elliptic; very bright; uniform, but owing to a hot wind too ill defined for detailed examination." On the next sweep, he saw it as "planetary nebula, or a decided pale blue colour, but not so full a blue as the planetary nebula [NGC 3918] ; oval; pos of the longer axis = 135 degrees approx.; 30 arcseconds long; 25 arcseconds broad; uniform and very bright; but not quite sharp at the edges." On a third occasion he called it "very bright, decidedly elliptic, a little dim at edges; colour very decided pale blue; diam in RA = 3s. Pos of longer axis about 130 degrees; pos of the nearer of two companion stars = 172 degrees." His final observation was "viewed past meridian; place from Piazzis' Catalogue. Somewhat hazy, with a slight nebulous atmosphere. Colour a decided blue; at all events a good sky-blue. Elliptic; pos of axis = 140 degrees; diam in RA 2.5s. Has 2 companion stars (a) pos = 173 deg. (b) pos = 137.8 deg." He sketched this and other planetary nebulae, commenting: "[these] represent planetary nebulae, a class of special interest, and of which, considering their general rarity, the southern heavens have afforded a rather unexpectedly large harvest. Those only are here delineatted which have either accompanying stars, or which are distinguished by some peculiarity, as ... [NGC 3242] which has a slight chevelure or nebulous haze exterior to its large oval disc; ..."
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.
The NGC description describes it as slightly elongated in PA 147 , 45" across with a blue colour.
Burnham, S. W. () "Measures of planetary nebulae with the 36-inch equatorial of the Lick Observatory", Pub. Lick Obs., vol 2, p159-167. "I have made the following measures of this interesting object:
direction of the longer axis of the ellipse 324.8°
Longer diameter of the whole ellipse 42.4''
shorter diameter 38.3''
longer diameter of inside ring 23.2''
shorter diameter of inside ring 17.0''
Journal BAA, 35, p159
A planetary with 11.3 mag (visual) cen.star, roughly elliptical bright inner ring 26''x16'' and outer much fainter oval disc 40''x35'' with, in parts, brighter edges. Lundmark notes that, according to Chinese chronicles, a Nova appeared in this region of the sky in AD 561, and suggests that theis planetary may be its relic.
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.
Photo Index by Jim Lucyk: Sky&Tel. 3/70 p203 (sketch by J. Herschel), Sky&Tel. 3/78 p213, Sky&Tel. 4/84 p382, Astronomy mag. 4/82 p12, Deep Sky #6 Sp84 p15, Deep Sky #23 Su88 p33, Deep Sky Monthly 10/81 p11, Burnhams V2 p1028, Burnhams V2 p1028, Burnhams V2 p1174.
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.
Observer: Chuck Layton; Your skills: Intermediate (some years); Date/time of observation: Feb. 2, 1998 0930 UT; Location of site: Tacoma,WA (Lat 47N, Elev 350ft); Site classification: Suburban; Sky darkness: 6 1-10 Scale (10 best); Seeing: 8 1-10 Seeing Scale (10 best); Moon presence: Major - gibbous or near object; Instrument: 8" f/6 Newtonian Eq.; Magnification: 38X, 76X, 244X; Filter(s): None, Lum. Deep Sky; Object(s): NGC 3242; Category: Planetary nebula; Class: 4 + 3b; Constellation: Hya; Data: mag 8.6 size 35"; Position: RA 10:24 DEC -18:38
Description: This nebula is a small to medium sized planetary that is fairly easy to distinquish from surrounding stars at low powers. It was a vivid blueish green at 76X. The central bright area was slightly triangular in shape with a small darker "lane" visible on the SE side extending outward from the center. In addition a slightly mottled edge was noticed with averted vision on the W to SW edge of the brighter center. A dimmer outer halo was uneven in brightness with a brighter, denser portion on the N side. The halo was elongated a bit to the SE. The central star was not visible.
This planetary is fun to observe because of all the minute and subtle details. A very captivating object. I probably spent over an hour describing, sketching and just plain admiring the thing. All this excitement, I'm sure, is due to the 2 hour sucker hole that opened up at midnight!!! I've had just about enough of El Nino this year, thanks!
Texereau and Sagot, in Revue des Constellations, write: "Easily visible, starlike in a 27mm 13x finder. Readily recognized as a planetary of appreciable size and with shaded edges in a 55mm refractor at 50x. Central part uniform and very bright in a 95mm refractor at 95x. Elliptical in a 200mm reflector at 200x. Central part grayish, and squared into a bright lozenge with a dimming outer edge, in a 215mm reflector at 375x. Colour bluish or yellow."
Hartung notes: "Photos indicate a central star 11.3 mag in a broad spindle 26 x 16 arcsec in pa 145 deg which lies in a fainter ellipse 40 x 35 arcsec. I have made out these features with 30cm, the spindle being brightest at the ends."
Houston notes that a 6-inch scope will show a bright central region as well as traces of a fainter outer envelope. "In my 5-inch moonwatch scope it is bright and easy . . since the surrounding field is poor, this planetary is quite eyecatching. It is ringlike, with a surface brightness only three times less than M57 . . I have used up to 150x on NGC 3242 without image breakdown. Under good conditions a 6-inch scope shows the 11th mag central star."
Tom Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "8.9M; 40" diameter; large, bright and round; 11.5M center star visible at 285x; annular bright ring apparent midway from center to outer edge; a.k.a. the "Cat's Eye"."
Steve Coe, observing with a 17.5" f/4.5 at 100X, notes: " Wow, Looks like CBS eye, greenish at all powers, Central star easy at 300X. Very bright, large, round. AT 650X on a night I rated 8/10 for seeing, there is a small, dark circular area around the central star. A very nice planetary with lots of internal detail at high power. Sentinel 13" 8/10--100X bright, pretty large, little elongated 1.2 X 1 PA 135, central star comes and goes with the seeing, light green or aqua. 220X--CBS eye obvious dark background and bright oval that encompassed the central star. Still very light green. UHC makes the central star disappear. 440X--Best view, several bright knots to southeast of central star, bright spots within CBS oval. High power shows the color as grey, not green, but high power brings out most detail, including central star and bright knots in disk.
Steve Coe (1992, The Deep-Sky Observer, Webb Society, Issue 1) observing with a 17.5-inch f/4.5 at 100x notes: "Wow, looks like a CBS eye, greenish at all powers. Central star easy at 300x. Very bright, large, round. At 650x on a night I rated 8/10 for seeing, there is a small dark circular area around the central star. A very nice planetary with lots of internal detail at high power."
(PK261+32.1) Mag=7.8. The "Ghost of Jupiter" is another star-party showpiece. Hydra: 10h, 24.8m; -18° 38' Though the famed early 19th-century observer Admiral Smyth found it to be pale greyish-white in his 6" equatorial refractor, Webb and most later authorities compare its hue to the pale blue of the planet Jupiter, which it resembles in angular diameter. In our 8" scope, the 45"x36" nebula was clearly tinted blue, like an otherworldly and ghostly rendition of our relatively nearby Jovian neighbor. A filter is not an absolute necessity, as the object readily will be apparent even in a moderately light-polluted sky.
Hartung does not mention colour, but says that on photographs it shows as a faint ellipse 40" by 35", inside of which is a brighter broad spindle 26" by 16" in PA 145 . He says that with a 12-inch he can make out these features, seeing the spindle brighter at the ends.
Mullaney calls it a "truly stunning pale blue planetary in Hydra .. this 9th magnitude object is as least 40 arcseconds by 35 arcseconds in extent. Visible in a 60mm refractor at 70x, it rivals the famous Ring nebula, M57, yet is unknown to many observers. The nucleus has shown strange variations over the years and should be monitored in 6-inch or larger telescopes."
William P. Clarke (San Diego, California, USA) writes in The Webb Society Nebulae and Clusters Section Report No. 11, January 1993: "A bright football-shaped structure with a darker centre containing the central star. A fainter, circular halo gives the nebula the appearance of an eye, or the CBS logo. The football-shaped part is elongated in PA 125 degrees and the overall diameter is 0.75'. The central star is obscured through the OIII filter, while the rest of the nebula is greatly enhanced. (21-inch f/20, x350)"
Observer: Steve Coe; Your skills: Advanced (many years); Date/time of observation: May 1995; Location of site: Sentinel, Arizona (Lat +32, Elev 1500); Site classification: Rural; Sky darkness: 8/10 1-10 Scale (10 best); Seeing: 8/10 1-10 Seeing Scale (10 best); Moon presence: None - moon not in sky; Instrument: 13" f/5.6 Newtonian, Bigfoot German mount; Magnification: 100, 220, 440X; Filter(s): UHC
Description: At 100X in the 13" this planetary is bright, pretty large, and little elongated 1.2X1 in PA 135 degree. The central star comes and goes and the nebula is light green or aqua in color. Going to 220X brings out lots of detail within the nebula. At higher power it has always resembled "The CBS eye". This is from the fact that there are two rings of brighter nebulosity within the disk of this planetary. The central star is held steady on this excellent evening. The best view is at 440X, there are several bright knots in the disk to the southeast of the central star, seen as bright spot within the "CBS" oval. High power lowers the color contrast so that the nebula is a very light green, but it does bring out many fine details with the planetary, including a narrow dark ring around the central star. Using the UHC filter at any of the higher powers makes the central star disappear and does not seem to enhance the contrast of any of the details.
Observer: Adam Albino; Your skills: Intermediate (some years); Date/time of observation: UTC: 1998/02/28 01:50; Location of site: Norwell, MA (Lat 42m 16.9s, Elev ); Site classification: Exurban; Sky darkness: 5.2 Limiting magnitude; Seeing: 4 1-10 Seeing Scale (10 best); Moon presence: None - moon not in sky; Instrument: 8" f/10 Ultima 8 PEC SCT - 80mm Mak f/10; Magnification: 101, 127, 169; Filter(s): UHC, NONE
Round, bright, with soft iridescent blue green glow. No real "ring" formation seen. Solid "ball" Structure. Skiff and Luginbuhl see some brightening on the NW side as well as some elongation (oval)in shape. I did not see this with the 8", although at higher powers I felt the edges were not as sharp. Interestingly I felt that the Mag. of the object was much higher then stated - easily 7.5. Very nice break from all those faint Fuzzy galaxys nearby!
Observer: Yann POTHIER (France) Your skill: advanced (many years) Object: NGC 3242 (PK 261-32.1; PN G261.0+32.0; ARO 4) Category: planetary nebula Constellation: HYA Object data: Vmag=7.7; Bmag=8.6; 40"x35"; type IIIb+IV; central star of Vmag=11.4; discovered by W. Herschel in 1785; ELCAT: [OIII, 496+501nm] = 17 x [Hbeta, 486nm]. RA/DE: 10h24.80m, -18°38.0' (2000.0) Date and UT of observation: 16 February 1994, early evening Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36) Site classification: rural, alt.1650m (5500ft) Limiting magnitude (visual in UMi): 6.2 Transparency (1 to 5 - best to worst): 1 Seeing (1 to 5 - best to worst): 3 Moon up (phase?): no Instrument: Coulter 445mm/17.5" F/4.5 Magnification: 145-312x Filters used: OIII
Description: at 145x, bright PN, medium sized (about 70"x49" on drawing), oval in a NW-SE axis; double-shell clearly seen, even without OIII filter; central part is annular but the ring is pinched on the SE side and has a brighter surface on the NW side; the inner ring is only 45"x35"; no central star visible.
Observer: Yann POTHIER (France) Your skill: advanced (many years) Object: NGC 3242 (PK 261-32.1; PN G261.0+32.0; ARO 4) Category: planetary nebula Constellation: HYA Object data: Vmag=7.7; Bmag=8.6; 40"x35"; type IIIb+IV; central star of Vmag=11.4; discovered by W. Herschel in 1785; ELCAT: [OIII, 496+501nm] = 17 x [Hbeta, 486nm]. RA/DE: 10h24.80m, -18°38.0' (2000.0) Date and UT of observation: 22 February 1990, ... Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36) Site classification: rural, alt.1650m (5500ft) Limiting magnitude (visual in UMi): 6.0 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: 36-150x Filters used: -
Description: at 36x, nebulous star, bright, contrasting with pinpoint nearby stars; at 72x, brighter center detached on the shell; at 100x, slightly oval, star near; at 150x, clearly oval with large brighter center.
This is a very impressive planetary nebula, showing a blue-green disk almost 1' in diameter with a bright center and fuzzy edges. I saw a bright spot on the SE edge, and another but fainter brightening to its NW."
P&K: lentic inner part, perhaps brtr part of halo in pa60.
7cm - vbr sm unifrm disk @ 30x making 30-60-90 triangle w/fntr *s S & E. best @ 110x, which shows lentic br core aligned SE-NW, and fntr circ collar. about 20' N/sl W is grp of m11-13 *s that appears nebulous @ 30x. BS, 14 Apr1993, Anderson Mesa.
15cm - 38x: pale blue and vbr, m8. 203x: br inner core w/fntr outer core. HM? - br spot occas noted on NW.
25cm - oval, elong E-W. diffuse edges. on NW side is br spot; otherwise featureless.
[amastro] posting, Sat Nov 25, 2006
82" telescope, McDonald Observatory near Fort Davis, Texas, USA
f/13.7, 35mm Televue Panoptic (5' fov, 812x)
Well, this might have been the best object of the weekend, Saturn notwithstanding. It was just as I remembered it to be when I viewed it through this same telescope in 2000, during the TSP. This PNe has a large slightly oval shape and shows multiple shells, with a bright central star, several other observers used the word "bagel". The innermost ring is small and dark, and had a purple-tinged outer edge. The next shell outwards is a bright crepe-like ring, shocking aqua in color. This is followed by a broader ring that is distinctly salmon or pink in color, my notes call it a "filling", and virtually everyone saw it this way. Lastly was another aqua ring, thinner than the pink ring, and not quite as vibrant in hue as the other aqua ring; it is almost perfectly uniform in width and looked like a racetrack. Curiously, the real-time view in this telescope looks nothing like any picture of this object that I have seen, and I've searched extensively to find a picture that even slightly resembles what I saw. None at all. To see this, I guess you need to book a night on the 82"...
Observers used to hunting planetary nebulae will find this object most impressive and a relief from the usual "stellar" or "stellar with faint outer envelope" descriptions. With an angular diameter larger than Saturn's, no "special tricks" are needed to see this object. Observing conditions, however, greatly influence the appearance of the nebula, and in a 15.5-inch at 220X it appears essentially void of structural detail, except for a fainter ridge which surrounds the brighter central elongated mass. This central disc appears featureless, although the Northern tip shows a slight brightening. No prominent colour was noted.
This planetary is clearly visible in a 10-inch f/5 at 30x, appearing as a bright bloated star; no matter how you try, you cannot focus it into a point. The starfield around it is pretty busy, containing bright and faint stars. I was surprised to see that it would be so large at 30x. However, even with the 10mm eyepiece, about 120x, the planetary does not show too well in this instrument. My last view was with an f/8 (the 15.5-inch) and the magnification quality was superior. The 10mm shows it as a large, pale disc, slightly elongated. The right eye shows it pale washed-out yellow, while it may have a bluish tinge with the left eye. When the numerous field stars are brought sharply into focus, the planetary still has a nebulous border, remaining fuzzy and not sharply terminated.
Sutherland (Huis Lana)
"Bertha" 12-inch f/4.8 Dobsonian (EP: 32mm, 25mm, 10mm, 6.3mm Plossls, 2x Barlow, 32mm Erfle)
Conditions: Clear, dark.
Always start your night with a bang. The first object of tonight's session was the Ghost of Jupiter, NGC 3242 in Hydra. At 120x it is an obvious target, making a triangle with two stars (V=9.9 & 11.4) southward (sketch). It is a large and bright planetary nebula with soft edges. Oval in shape, with a large, approximately circular, smooth, inner disc. (0.8' x 0.6', SSE-NNW). (D: 20090129/30. Own star charts)
Location: Campsite (23 16 South 29 26 East)
Sky conditions: 7 magnitude clear.
Instrument: Meade 8" (Super wide angle 18mm eyepiece)
Outstanding bright planetary nebula with round sharp edges and a bluish colour. On both sides of this planetary nebula double stars can be seen. I estimate this planetary about 8 to 9 magnitude in brightness.
12-inch f/10 SCT (EP: 2-inch 32mm SW 95x 42' fov; 2-inch 14mm UW 218x 23' fov)
Outstanding bright, slightly oval planetary nebula, also known as the "Ghost of Jupiter". Well defined, although with a soft outer envelope. I noticed a washed out blue colour and the faint 12th magnitude star in the centre (218x). Appears somewhat mottled and resembles a human eye form in contrast to an inner envelope around the star. A faint darkish area can be seen in the southern section, with a brighter northern side. Poor star-field which host two stars visible to the south and east. William Herschel viewed this puffball in February 1785.
Sky Conditions: Clear
Quality of Observation: Very Good
Bill Hollenbach's Pad
6" Dobsonian, 25mm & 10mm Eyepieces
Compared with the Ring Nebula (M57), NGC 3242 (Ghost Of Jupiter) is the brighter one of the two. NGC 3242 shines brightly with a blue-green tint to it. Even with a 10mm eyepiece the image is still breathtaking and appears egg-shaped. This planetary nebula certainly is worth the effort as it is not easily detectable as it is low on the western horizon and observed a couple of hours after sunset, but under dark sky conditions makes for a welcome and breathtaking object to observe.
Sky Conditions:The fainter parts of the Milky Way are barely visible.Haziness only visible on the horizon.Atmosphere stable with little interference.
This planetary nebula has an oval-like shape which is well defined at both 167x and 214x and that this nebula is seen as a bluish-green haze of soft light at 214x.This planetary nebula measures 8.2'x 6.8'.Chart No:214,NSOG,Vol.2.
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 fuzzy snowball.
Chart Number:No.10(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:In the middle of this planetary nebula it grows brighter.
Challenge Rating:Breathtaking Sight.
The edge of this planetary nebula is sharply defined and this nebula has an oval shape in the centre which looks bipolar.The surface of this planetary nebula has a greenish surface.
Observing site: Pinnacles overlook
[10h 24m 48s, -18° 38' 0"] A light blue featureless disk with fuzzy edges. It appeared to be about 20" in diameter to me. The outer envelope was not visible. This was observed through the foliage of the cherry tree, so it is not too surprising that little was seen.
Observing site: Pinnacles overlook
[10h 24m 48s, -18° 38' 0"] Bright, slightly mottled, a pale blue.
Observing site: Pinnacles overlook
[10h 24m 48s, -18° 38' 0"] Very nice. Like NGC 7662 in Andromeda. Round, no central star seen.
Telescope: 12" Dobsonian – f4,9. Eyepiece 15mm. FOV- 36'
Sky conditions: Seeing 3/5 (intermittent high cloud cover)
Actual dimensions: 20.8' x 20.8' (Cartes Du Ciel)
Planetary nebula in Hydra
A bright creamy yellowy disk surrounded by a bright irregular shell which does give it a "ghostly" appearance. After reducing and rotating the object , the ghost looks quite surprised!
Two very bright stars W of nebula. To the N just inside fov four stars form trapezium.
The Messier objects
The Bennett objects
The Caldwell list
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