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Nebulae Gallery :
 Click images for close-up
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Veil Nebula - NGC 6960, NGC 6979, NGC 6992 and NGC 6995 (Wide-Field)
July 23, 2009 - Table Mountain Star Party
The Veil Nebula, is part of the Cygnus Loop, radio source W78, or Sharpless 103. Other parts of the loop include the 'Eastern Veil', the 'Western Veil' or 'Witch's Broom Nebula', and Pickering's Triangular Wisp. It is a large, relatively faint supernova remnant in the constellation Cygnus. The source supernova exploded some 5,000 to 8,000 years ago, and the remnants have since expanded to cover an area of ~3x3 degrees; about 6 times the diameter or 36 times the area of a full moon. The distance to the nebula is not precisely known, with estimates ranging from 1,400 to 2,600 light-years. It was discovered on 1784 September 5 by William Herschel. He described the western end of the nebula as "Extended; passes thro ' 52 Cygni... near 2 degree in length." and described the eastern end as "Branching nebulosity... The following part divides into several streams uniting again towards the south."
The Hubble Space Telescope captured images of the nebula. The analysis of the emissions from the nebula indicate the presence of oxygen, sulfur, and hydrogen. When finely resolved, some parts of the image appear to be rope like filaments. The standard explanation is that the shock waves are so thin, less than one part in 50,000 of the radius, that the shell is only visible when viewed exactly edge-on, giving the shell the appearance of a filament. Undulations in the surface of the shell lead to multiple filamentary images, which appear to be intertwined.
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Lagoon Nebula - M8 (Wide-Field)
July 21, 2009 - Table Mountain Star Party
The Lagoon Nebula (catalogued as Messier 8 or M8, and as NGC 6523) is a giant interstellar cloud in the constellation Sagittarius. It is classified as an emission nebula and as an H II region. The Lagoon Nebula was discovered by Guillaume Le Gentil in 1747 and is one of only two star-forming nebulae faintly visible to the naked eye from mid-northern latitudes. Seen with binoculars, it appears as a distinct oval cloudlike patch with a definite core. A fragile star cluster appears superimposed on it. The Lagoon Nebula is estimated to be 4,100 light-years from the Earth. In the sky of Earth, it spans 90' by 40', translates to an actual dimension of 110 by 50 light years. Like many nebulas, it appears pink in time-exposure color photos but is gray to the eye peering through binoculars or a telescope, human vision having poor color sensitivity at low light levels.
The nebula contains a number of Bok globules - dark, collapsing clouds of protostellar material - the most prominent of which have been catalogued by E. E. Barnard as B88, B89 and B296. It also includes a funnel-like or tornado-like structure caused by a hot O-type star that pours out ultraviolet light, heating and ionizing gases on the surface of the nebula. The Lagoon Nebula also contains at its centre a structure known as the "Hourglass Nebula" (so named by John Herschel), which should not be confused with the better known Hourglass Nebula in the constellation of Musca. In 2006 the first four Herbig-Haro objects were detected within the Hourglass, also including HH 870. This provides the first direct evidence of active star formation by accretion within it.
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North America Nebula - NGC 7000 (Wide-Field)
July 20, 2009 - Table Mountain Star Party
The North America Nebula (NGC 7000 or Caldwell 20) is an emission nebula in the constellation Cygnus, close to Deneb (the tail of the swan and its brightest star). It was discovered by William Herschel on October 24th 1786 from Slough England. The remarkable shape of the emission nebula resembles that of the continent of North America, complete with a prominent Gulf of Mexico. It is sometimes wrongly called the "North American" nebula. The North America Nebula is large, covering an area of more than four times the size of the full moon, but its surface brightness is low so normally it cannot be seen with the unaided eye. Binoculars and telescopes with large fields of view (approximately 3°) will show it as a foggy patch of light under sufficiently dark skies. However, using a UHC filter which filters out some unwanted wavelengths of light, it can be seen by the naked eye under dark skies.
Its prominent shape and especially its reddish color (from the hydrogen Ha emission line) only show up in photographs of the area. The North America Nebula and the nearby Pelican Nebula, (IC 5070) are in fact parts of the same interstellar cloud of ionized hydrogen (H II region). Between the Earth and the nebula complex lies a band of interstellar dust that absorbs the light of stars and nebulae behind it and thereby is responsible for the shape as we see it. The distance of the nebula complex is not precisely known, nor is the star responsible for ionizing the hydrogen so that it emits light. If the star inducing the ionization is Deneb, as some sources say, the nebula complex would be about 1800 light years distance, and its absolute size (6° apparent diameter on the sky) would be 100 light years.
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Emission Nebula - IC 1396 (Wide-Field)
July 19, 2009 - Table Mountain Star Party
Sprawling across hundreds of light-years, emission nebula IC 1396 mixes glowing cosmic gas and dark dust clouds. Stars are forming in this area, only about 3,000 light-years from Earth. The red glow in IC 1396 and across the image is created by cosmic hydrogen gas recapturing electrons knocked away by energetic starlight. The dark dust clouds are dense groups of smoke-like particles common in the disks of spiral galaxies. Among the intriguing dark shapes within IC 1396, the winding Elephant's Trunk nebula lies just right of the nebula's center. IC 1396 lies in the high and far off constellation of Cepheus.
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Orion Nebula - M42
January 19, 2009
The Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a diffuse nebula situated south of Orion's Belt. It is one of the brightest nebulae, and is visible to the naked eye in the night sky. M42 is located at a distance of 1,270 ± 76 light years and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light years across. Older texts frequently referred to the Orion Nebula as the Great Nebula in Orion or the Great Orion Nebula. Yet older, astrological texts refer to it as Ensis (Latin for "sword"), which was also the name given to the star Eta Orionis, which can be seen close to the nebula from Earth.
The Orion Nebula is one of the most scrutinized and photographed objects in the night sky, and is among the most intensely studied celestial features. The nebula has revealed much about the process of how stars and planetary systems are formed from collapsing clouds of gas and dust. Astronomers have directly observed protoplanetary disks, brown dwarfs, intense and turbulent motions of the gas, and the photo-ionizing effects of massive nearby stars in the nebula. There are also supersonic "bullets" of gas piercing through the dense hydrogen clouds of the Orion Nebula. Each bullet is ten times the diameter of Pluto's orbit and are tipped with iron atoms glowing bright blue. They were probably formed one thousand years ago from an unknown violent event.
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Thor's Helmet - NGC 2359
January 1, 2009
NGC 2359 (also known as Thor's Helmet) is in the constellation Canis Major. The nebula is approximately 15,000 light-years away and 30 light years in size. Known as a Wolf-Rayet star, the central star is an extremely hot giant thought to be in a brief, pre-supernova stage of evolution. It is similar in nature to the Bubble Nebula, interactions with a nearby large molecular cloud are thought to have contributed to the more complex shape and curved bow-shock structure of Thor's Helmet. It is also Sharpless catalog Sh2-298 and Gum catalog 4. This ring-shaped nebulosity results from the interaction between the stellar wind of a central Wolf-Rayet star and the interstellar matter. The wind compresses the interstellar matter and produces a bubble of gas around the star.
This bubble could be compared to the piles of snow that form in front of a snow plough, and which move and grow as the plough advances. The bubble expands around the Wolf-Rayet star and as it ploughs through the interstellar medium, it enriches itself with more gas and dust. The bubble's mass is estimated to be about twenty times the mass of the Sun. The emission from the nebula comes from the interaction between the ultraviolet photons emitted by the star and the gas in the bubble. NGC 2359 is quite different than a planetary nebula. Its Wolf-Rayet central star is a massive and very young star while for planetary nebulae the central star is a very old star in an advanced state of evolution. Such a star is less massive and on its way to becoming a white dwarf.
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Rosette Nebula - NGC 2237
January 1, 2009
The Rosette Nebula is a large, circular H II region located near one end of a giant molecular cloud in the Monoceros region of the Milky Way Galaxy. The open cluster NGC 2244 is closely associated with the nebulosity, the stars of the cluster having been formed from the nebula's matter. The cluster and nebula lie at a distance of some 5,200 light years from Earth (although estimates of the distance vary considerably) and measure roughly 130 light years in diameter. The radiation from the young stars excite the atoms in the nebula, causing them to emit radiation themselves producing the emission nebula we see.
The mass of the nebula is estimated to be around 10,000 solar masses. It is believed that stellar winds from a group of O and B stars are exerting pressure on interstellar clouds to cause compression, followed by star formation in the nebula. This star formation is currently still ongoing. A survey of the nebula with the Chandra X-ray Observatory in 2001 has revealed the presence of very hot, young stars at the core of the Rosette Nebula. These stars have heated the surrounding gas to a temperature in the order of 6 million kelvins causing them to emit copious amounts of X-rays.
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Pacman Nebula - NGC 281
December 31, 2008
NGC 281 is an H II region in the constellation of Cassiopeia and part of the Perseus Spiral Arm. It includes the open cluster IC 1590, the multiple star HD 5005, and several Bok globules. Colloquially, NGC 281 is also known as the Pacman Nebula for its resemblance to the video game character. The nebula was discovered in August 1883 by E. E. Barnard, who described it as "a large faint nebula, very diffuse." The multiple star HD 5005, also called ß1, was discovered by S. W. Burnham. It consists of an 8th-magnitude primary with four companions at distances between 1.4 and 15.7 seconds of arc.
There has been no appreciable change in this quintuple system since the first measurements were made in 1875.The nebula is visible in amateur telescopes from dark sky locations. In his book Deep Sky Wonders, Walter Scott Houston describes the appearance of the nebula in small telescopes: "There was a faint glow in the immediate vicinity of the multiple star, with an occasional impression of a much larger nebulosity...Its surface brightness was much less than that of M33 in Triangulum or NGC 205, the distant companion of the Andromeda galaxy."
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Flaming Star Nebula - IC 405
December 28, 2008
IC 405, also Sharpless 229 (Sh2-229), Caldwell 31 and The Flaming Star Nebula, is an emission/reflection nebula and Caldwell object in the constellation Auriga, surrounding the bluish star AE Aurigae. It shines at magnitude +6.0. It surrounds the irregular variable star AE Aurigae and is located near the emission nebula IC 410, the open cluster M38, and the naked-eye K-class star Hassaleh. The nebula measures approximately 37.0' x 19.0', and lies about 1,500 light-years away. It is believed that the proper motion of the central star can be traced back to the Orion's Belt area. The nebula is about 5 light-years across.
Rippling dust and gas lanes give the Flaming Star Nebula its name. The red and purple colors of the nebula are present in different regions and are created by different processes. The bright star AE Aurigae, is so hot it is blue, emitting light so energetic it knocks electrons away from surrounding gas. When a proton recaptures an electron, red light is frequently emitted. The purple region's color is a mix of this red light and blue light emitted by AE Aurigae but reflected to us by surrounding dust. The two regions are referred to as emission nebula and reflection nebula, respectively.
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Horsehead Nebula - IC 434
December 1, 2008
The Horsehead Nebula (also known as Barnard 33 in bright nebula IC 434) is a dark nebula in the constellation Orion. The nebula is located just below Alnitak, the star farthest left on Orion's Belt, and is part of the much larger Orion Molecular Cloud Complex. It is approximately 1500 light years from Earth. It is one of the most identifiable nebulae because of the shape of its swirling cloud of dark dust and gases, which is similar to that of a horse's head. The shape was first noticed in 1888 by Williamina Fleming on photographic plate B2312 taken at the Harvard College Observatory.
The red glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. The darkness of the Horsehead is caused mostly by thick dust, although the lower part of the Horsehead's neck casts a shadow to the left. Streams of gas leaving the nebula are funneled by a strong magnetic field. Bright spots in the Horsehead Nebula's base are young stars just in the process of forming.
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Crab Nebula - M1
December 1, 2008
The Crab Nebula (catalogue designations M1, NGC 1952, Taurus A) is a supernova remnant and pulsar wind nebula in the constellation of Taurus. First observed in 1731 by John Bevis, the Crab Nebula corresponds to the bright SN 1054 supernova that was recorded by Chinese and Arab astronomers in 1054 CE. The nebula was the first astronomical object identified with a historical supernova explosion. The nebula was independently rediscovered in 1758 by Charles Messier as he was observing a bright comet. Messier catalogued it as the first entry in his catalogue of comet-like objects. The Earl of Rosse observed the nebula at Birr Castle in the 1840s, and referred to the object as the Crab Nebula because a drawing he made of it looked like a crab.
Located at a distance of about 6,500 light-years (2 kpc) from Earth, the nebula has a diameter of 11 ly (3.4 pc) and expands at a rate of about 1,500 kilometers per second. At the center of the nebula lies the Crab Pulsar, a rotating neutron star, which emits pulses of radiation from gamma rays to radio waves with a spin rate of 30.2 times per second. The nebula acts as a source of radiation for studying celestial bodies that occult it. In the 1950s and 1960s, the Sun's corona was mapped from observations of the Crab's radio waves passing through it, and more recently, the thickness of the atmosphere of Saturn's moon Titan was measured as it blocked out X-rays from the nebula. At X-ray and gamma-ray energies above 30 KeV, the Crab is generally the strongest persistent source in the sky, with measured flux extending to above 1012 eV.
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Crystal Ball - NGC 1514
November 21, 2008
NGC 1514 was discovered by William Herschel on November 13th 1790 describing it "a most singular phoenomenoa" and forcing him to rethink his ideas on the construction of the heavens. Up until this point Herschel was convinced that all nebulae consisted of masses of stars too remote to resolve, but now here was a single star "surrounded with a faintly luminous atmosphere." He went on to conclude "Our judgement I may venture to say, will be, that the nebulosity about the star is not of a starry nature". It has since been conjectured that the nebula in fact envelops a tightly orbiting double star with a period of 4 to 10 days. If there are two stars at the heart of this nebula- the more massive one, which eventually shed its outer envelope, was probably 3-4 times as massive as our Sun. Measurements of the gas near center indicate that it is expanding outwardly at 25 kilometers per second.
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Bubble Nebula - NGC 7635
October 6, 2008
NGC 7635 (also known as the Bubble Nebula) in the constellation Cassiopeia is a H II region, emission nebula. It lies close to the direction of the open cluster Messier 52. At the center of the nebula is an 8th magnitude star, and about 6 arc minutes southwest is a brighter star (the brightest star in this image) of magnitude 6.7. The Bubble nebula is a very rare example of a planetary nebula around an OB star. In our own galaxy, there are only two known examples: the Bubble Nebula and NGC 6164-5. Planetary nebulae form when aging stars lose mass via stellar winds. The wind sweeps up the surrounding medium around the star into a shell, which can appear as a ring or other shapes around the central star due to the effects of perspective and viewing angle. The "Bubble" is created by the stellar wind from a massive hot, 8.7 magnitude young central star, the 15 ± 5 Solar mass SAO 20575 (BD+60 2522). The nebula is near a giant molecular cloud which contains the expansion of the bubble nebula while itself being excited by the hot central star, causing it to glow.
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Crescent Nebula - NGC 6888
September 21, 2009
The Crescent Nebula (NGC 6888 or Caldwell 27) is an emission nebula in the Cygnus constellation, about 5000 light years away. The Nebula is formed by the fast stellar wind from it's Wolf-Rayet calss central star WR 136 (HD 192163) colliding with and energizing the slower moving wind ejected by the star when it became a red giant around 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The cosmic bubble is about 25 light-years across and is blown by winds from its central, bright, massive star. The inward moving shock wave heats the stellar wind to X-ray emitting temperatures. The star is shedding its outer envelope in a strong stellar wind, ejecting the equivalent of the Sun's mass every 10,000 years. The nebula's complex structures are likely the result of this strong wind interacting with material ejected in an earlier phase. Burning fuel at a prodigious rate and near the end of its stellar life this star should ultimately go out with a bang in a spectacular supernova explosion.
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Iris Nebula - NGC 7023
August 10, 2008
The Iris Nebula, also NGC 7023 and Caldwell 4, is a bright reflection nebula and Caldwell object in the constellation Cepheus. NGC 7023 is actually the cluster within the nebula, LBN 487, and the nebula is lit by a magnitude +7 star, SAO 19158. It shines at magnitude +6.8 and is located near the Mira-type variable star T Cephei, and near the bright magnitude +3.23 variable star Beta Cephei (Alphirk). It lies 1,300 light-years away and is six light-years across. NGC 7023 was observed 18 October 1794 by William Herschel. It is located about 3.5 degrees south west of Beta Cephei (Alfirk). This is a wonderful example of a reflection nebula. Its unusual structure gave rise to the name, the Iris Nebula.
The nebula is illuminated by light for a Mag 6.8 star (HD200775) in its center. The bright blue light seen here is due to light being reflected off dust particles that survived the star's birth. There are faint hints of red color surrounding the central star. This is evidence of some hydrogen emission taking place. Images of this object frequently capture the dense dust cloud that it resides in. There is also and open cluster of stars associated with NGC 7023 that is known as Collinder 427. This loose open cluster is located on the west side of the reflection nebula within the dark region above the "petal" structure of the Iris.
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Dumbbell Nebula - M27
August 8, 2008
The Dumbbell Nebula (also known as Messier 27, M 27, or NGC 6853) is a planetary nebula in the constellation Vulpecula, at a distance of about 1,360 light years. This object was the first planetary nebula to be discovered - by Charles Messier in 1764. At its brightness of visual magnitude 7.5 and its diameter of about 8 arcminutes, it is easily visible in binoculars, and a popular observing target in amateur telescopes. This planetary nebula appears to be shaped like an prolate spheroid and is viewed from our perspective along the plane of its equator. In 1992, Moreno-Corral et al. computed that the rate of expansion in the plane of the sky of this planetary nebula was no more than 2.3° per century. From this, an upper limit to the age of 14,600 yr may be determined. In 1970, Bohuski, Smith, and Weedman found an expansion velocity of 31 km/s.
Given its semi-minor axis radius of 1.01 ly, this implies that the kinematic age of the nebula is some 9,800 years. Like many nearby planetary nebulae, the Dumbbell contains knots. Its central region is marked by a pattern of dark and bright cusped knots and their associated dark tails (see picture). The knots vary in appearance from symmetric objects with tails to rather irregular tail-less objects. Similarly to the Helix Nebula and the Eskimo Nebula, the heads of the knots have bright cusps which are local photoionization fronts. The central star, a white dwarf, is estimated to have a radius which is 0.055 ± 0.02 R which gives it a size larger than any other known white dwarf. The central star mass was estimated in 1999 by Napiwotzki to be 0.56 ± 0.01 M.
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Ring Nebula - M57
August 7, 2008
The famously named "Ring Nebula" is located in the northern constellation of Lyra, and also catalogued as Messier 57, M57 or NGC 6720. It is one of the most prominent examples of the deep-sky objects called planetary nebulae (singular, planetary nebula), often abbreviated by astronomers as simply planetaries or PN. M57 is located in Lyra, south of its brightest star Vega. Vega is the northeastern vertex of the three stars of the Summer Triangle. M57 lies about 40% of the angular distance from beta-Lyrae to gamma-Lyrae. M57 is best seen through at least a 20 cm (8-inch) telescope, but even a 7.5 cm (3-inch) telescope will show the ring. Larger instruments will show a few darker zones on the eastern and western edges of the ring, and some faint nebulosity inside the disk.
This nebula was discovered by Antoine Darquier de Pellepoix in January, 1779, who reported that it was "...as large as Jupiter and resembles a planet which is fading." Later the same month, Charles Messier independently found the same nebula while searching for comets. It was then entered into his catalogue as the 57th object. Messier and William Herschel also speculated that the nebula was formed by multiple faint stars that were unable to resolve with his telescope. In 1800, Count Friedrich von Hahn discovered the faint central star in the heart of the nebula. In 1864, William Huggins examined the spectra of multiple nebulae, discovering that some of these objects, including M57, displayed the spectra of bright emission lines characteristic of fluorescing glowing gases. Huggins concluded that most planetary nebulae were not composed of unresolved stars, as had been previously suspected, but were nebulosities.
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Eagle Nebula - M16
August 3, 2008
The Eagle Nebula (also known as Messier Object 16, M16 or NGC 6611), perhaps one of the most famous and easily recognized space objects, is a young open cluster of stars in the constellation Serpens, discovered by Jean-Philippe de Cheseaux in 1745-46. It is associated with a diffuse emission nebula, or H II region, which is catalogued as IC 4703. This region of active current star formation is about 7,000 light-years distant. The brightest star in the nebula has an apparent magnitude of 8.24, easily visible with good binoculars. Images made in 1995 by the Hubble Space Telescope greatly improved our understanding of processes inside the nebula. The region of the Eagle Nebula known as the "Pillars of Creation" is a large region of star formation. Its small dark areas are believed to be protostars.
The pillar structure of the region resembles that of another, much larger star formation region, imaged by Spitzer Space Telescope in 2005 in Cassiopeia, which is designated W5 and usually called "Mountains of Creation". Combination of an X-ray image from the Chandra observatory with Hubble's Pillars image have shown that X-ray sources (from young stars) do not coincide with the pillars, instead randomly dotting the area. This suggests that star formation may have peaked approximately one million years ago in the Eagle Nebula and any protostars in the pillar EGGs are not yet hot enough to emit X-rays. In early 2007 scientists using the Spitzer discovered evidence that the Pillars were likely destroyed by a supernova explosion about 6,000 years ago, but the light showing the new shape of the nebula will not reach Earth for another millennium.
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Pelican Nebula - IC 5070 and IC 5067
July 31, 2008
The Pelican Nebula (also known as IC5070 and IC5067) is an H II region associated with the North America Nebula in the constellation Cygnus. The nebula resembles a pelican in shape, hence the name. The Pelican Nebula is a large area of emission nebula in the constellation Cygnus (the Swan), close to Deneb, and divided from its brighter, larger neighbor, the North America Nebula, by a molecular cloud filled with dark dust. The Pelican is much studied because it has a particularly active mix of star formation and evolving gas clouds. The light from young energetic stars is slowly transforming cold gas to hot and causing an ionization front gradually to advance outward. Particularly dense filaments of cold gas are seen to still remain. Millions of years from now this nebula might no longer be known as the Pelican, as the balance and placement of stars and gas will leave something that appears completely different.
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Veil Nebula (East) - NGC 6992
July 29, 2008
Special Note: This is the "First Light Image" from my Takahashi - FSQ-106EDX "New-Q" Astrograph.
The Veil Nebula (East) is part of the Cygnus Loop and is a large, relatively faint supernova remnant in the constellation Cygnus. The source supernova exploded some 5,000 to 8,000 years ago, and the remnants have since expanded to cover an area of 3 degrees; about 6 times the size of a full moon. The distance to the nebula is not precisely known, with estimates ranging from 1,400 to 2,600 light-years. It was discovered on 1784 September 5 by William Herschel. He described the eastern end as "Branching nebulosity... The following part divides into several streams uniting again towards the south." When finely resolved, some parts of the image appear to be rope like filaments. The standard explanation is that the shock waves are so thin, less than one part in 50,000 of the radius, that the shell is only visible when viewed exactly edge-on, giving the shell the appearance of a filament. Undulations in the surface of the shell lead to multiple filamentary images, which appear to be intertwined.
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