Planetary Nebula Abell 21 Medusa Nebula

2. Planetary NebulaAbell 21Medusa Nebula Abell 21 is a large planetary nebula located about 1,500 light-years away in Gemini. It was originally discovered in 1955 by UCLA astronomer George O. Abell, who classified it as an old planetary nebula. The braided serpentine filaments of glowing gas suggests the serpent hair of Medusa found in ancient Greek mythology.

3. Planetary NebulaESO 172-7Boomerang Nebula This reflecting cloud of dust and gas has two nearly symmetric lobes of matter that are being ejected from a central star. Each lobe of the nebula is nearly one light-year in length, making the total length of the nebula half as long as the distance from our Sun to our nearest neighbor - Alpha Centauri. The Boomerang Nebula is located about 5,000 light-years from Earth in the direction of the Southern constellation Centaurus.

4. Planetary NebulaHD 44179Red Rectangle Nebula Hubble's sharp pictures show that the Red Rectangle is not really rectangular, but has an overall X-shaped structure, which the astronomers interpret as arising from outflows of gas and dust from the star in the center. The outflows are ejected from the star in two opposing directions, producing a shape like two ice-cream cones touching at their tips. This infrared source lies about 2,300 light-years from Earth in the direction of the constellation Monoceros. Stars surrounded by clouds of dust are often strong infrared sources because the dust is heated by the starlight and radiates long-wavelength light.

5. Planetary NebulaHubble 5Double Bubble Nebula Hubble 5 is a striking example of a "butterfly" or bipolar (two-lobed) nebula. The heat generated by fast winds causes each of the lobes to expand, much like a pair of balloons with internal heaters.

6. Planetary NebulaIC 418Spirograph Nebula Glowing like a multi-faceted jewel, this image from Hubble reveals some remarkable textures weaving through the nebula - their origins still uncertain. Over the next several thousand years, the nebula will gradually disperse into space; the white dwarf star will cool and slowly fade away, taking billions of years. Our Sun is expected to undergo a similar fate, but fortunately this will not occur until some 5 billion years from now. IC 418 lies about 2,000 light-years from Earth in the direction of the constellation Lepus.

7. Planetary NebulaIC 3568Lemon Slice Nebula IC 3568 is an example of a round planetary nebula with a bright inner shell and fainter, smooth, circular outer envelope. The Lemon slice nebula is one of the most simple nebulae known, with an almost perfectly spherical shape. It appears very similar to a lemon for which it is named. The central star is a very hot and bright Red Giant, and can be seen as a red-orange hue. IC 3568 lies in the constellation Camelopardalis at a distance of about 9,000 light-years.

8. Planetary NebulaIC 4406Retina Nebula Like many other planetary nebulae, IC 4406 exhibits a high degree of symmetry; the left and right halves are nearly mirror images of the other. If we could fly around IC 4406 in a starship, we would see that the gas and dust form a vast donut of material streaming outward from the dying star. This Hubble side view allows us to see the intricate tendrils of dust that have been compared to the eye's retina. One of the most interesting features of IC 4406 is the irregular lattice of dark lanes that criss-cross the center of the nebula. These lanes are about 160 au wide.

9. Planetary NebulaM2-9Butterfly Nebula Stars transform themselves from normal stars to white dwarfs by casting off their outer gaseous envelopes. In the center of M2-9, two stars orbit inside a gaseous disk 10 times the diameter of Pluto’s orbit. The expelled envelope of the dying star breaks out from the disk creating the bipolar appearance. M2-9 is 2,100 light-years away in the constellation Ophiucus.

10. Planetary NebulaM27Dumbbell Nebula Like other nebula of its type, M27 is a bubble of gas that has been ejected by a star at the end if its life. The core of the star still remains in the center (the slightly blue-ish star in the center above the small triangle of white stars) and makes this gas bubble glow. M27 is estimated to be 3,500 years old and about 1,000 light years away toward the constellation Vulpecula.

11. Planetary NebulaM57Ring Nebula This image from Hubble shows a dying star floating in a blue haze of hot gas. Surrounding the star is a barrel of gas that forms a “ring” around the star. The photo reveals elongated dark clumps of material embedded in the gas at the edge of the nebula. The nebula is about a light-year in diameter and is located some 2,000 light-years away in the direction of the constellation Lyra.

12. Planetary NebulaMyCn 18Hourglass Nebula This Hubble image reveals the hourglass shape of MyCn18 with an intricate pattern of "etchings" in its walls. Scientists believe the hourglass shape is produced by the expansion of a fast stellar wind within a slowly expanding cloud which is more dense near its equator than near its poles. The hot star which has been thought to eject and illuminate the nebula, and therefore expected to lie at its center of symmetry, is clearly off center. An unseen companion star may be the explaination for the structure. MyCn18 is located about 8,000 light-years away.

13. Planetary NebulaMenzel 3 or Mz 3Ant Nebula From ground-based telescopes, the "ant nebula" (Menzel 3, or Mz 3) resembles the head and thorax of a garden-variety ant. This Hubble image, showing 10 times more detail, reveals the "ant's" body as a pair of fiery lobes protruding from a dying, Sun-like star. How does a spherical star produce such a non-spherical symmetry in the gas that it ejects? Scientists think perhaps a closely orbiting companion star exerts strong gravitational tidal forces, which shape the out-flowing gas, or possibility, as the dying star spins, its strong magnetic fields are wound up into complex shapes.

14. Planetary NebulaNGC 2237Rosette Nebula Inside the Rosette Nebula lies a cluster of bright, massive, young stars whose strong stellar winds and radiation have cleared a hole in the nebula's center. Ultraviolet light from these hot stars excites the surrounding nebula, causing it to glow. Star formation is still active around the nebula, as proven by the presence of a very young infrared star (AFGL 961) still in its final stages of formation. The young massive stars in the nebula will one day blow all the gas and dust away. The Rosette nebula is about 4,500 light-years away, in the direction of the constellation of Monoceros.

15. Planetary NebulaNGC 2392Eskimo Nebula In this Hubble image, the "parka" is really a disk of material embellished with a ring of comet-shaped objects, with their tails streaming away from the central, dying star. The bright central region, resembling a ball of twine, is a bubble of material being blown into space by the central star’s intense “wind” of high-speed material. The nebula's glowing gases produce the colors in this image: nitrogen (red), hydrogen (green), oxygen (blue), and helium (violet). The Eskimo Nebula is about 5,000 light-years from Earth in the constellation Gemini.

16. Planetary NebulaNGC 2440 NGC 2440 is another planetary nebula ejected by a dying star.The central star of NGC 2440 is one of the hottest known with a surface temperature near 200,000 degrees Celsius. The nebula is also rich in clouds of dust, some of which form long, dark streaks pointing away from the central star. NGC 2440 lies about 4,000 light years from Earth.

17. Planetary NebulaNGC 2818 The spectacular structure of NGC 2818 contains the outer layers of a star that were expelled into interstellar space. The glowing gaseous shrouds in the nebula were shed by the central star after it ran out of fuel to sustain the nuclear reactions in its core. Planetary nebulae fade gradually over tens of thousands of years. The hot remnant stellar core of NGC 2818 will eventually cool off for billions of years as a white dwarf. NGC 2818, which lies in the southern constellation of Pyxis (the Compass).

18. Planetary NebulaNGC 3132Eight-Burst or Southern Ring Nebula It’s the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. The pool of light seen surrounding this binary system is energized by the hot surface of the faint star. Blue represents the hottest gas, which is confined to the inner region of the nebula. Red represents the coolest gas, at the outer edge. NGC 3132 is nearly half a light year in diameter, and at a distance of about 2000 light years is one of the nearer known planetary nebulae. The gases are expanding away from the central star at a speed of 9 miles per second.

19. Planetary NebulaNGC 3242Ghost of Jupiter Nebula A notable feature of the nebula is the presence of the two red 'fliers' on both poles of the nebula. The gas comprising these objects is believed to be younger and moving at a much faster rate than that of the nebula. It is also sometimes referred to as the Eye Nebula.

20. Planetary NebulaNGC 3918Blue Planetary Nebula In the center of the cloud of gas, and completely dwarfed by the nebula, are the dying remnants of a red giant. During the final convulsive phase in the evolution of these stars, huge clouds of gas are ejected from the surface of the star before it emerges from its cocoon as a white dwarf. Planetary nebula NGC 3918 is about 4900 light-years from Earth in the constellation of Centaurus.

21. Planetary NebulaNGC 5189Spiral Planetary Nebula A spectacular example of the final stages in the life of a medium-sized star can be seen in the beautiful complexity of the bluish lobes of NGC 5189. As a result of the mass-loss process, the planetary nebula has been created with two nested structures, tilted with respect to each other, that expand away from the center in different directions. The bright golden ring that twists and tilts through the image is made up of a large collection of radial filaments and cometary knots. These are usually formed by the combined action of photo-ionizing radiation and stellar winds.

22. Planetary NebulaNGC 5307Spiral-Structured Planetary Nebula Some stellar nebulae are strangely symmetric. NGC 5307 is an example of a planetary nebula with a spiral shape. Spiral planetary nebulae are thought to be caused by a bright central white dwarf star expelling a symmetric wobbling jet of rapidly moving gas. NGC 5307 lies in Centaurus and is about 10,000 light-years away and has a diameter of approximately 0.6 light-year.

23. Planetary NebulaNGC 6302Bug Nebula or Butterfly Nebula What resemble dainty butterfly wings are actually roiling cauldrons of gas heated to more than 36,000 degrees Fahrenheit. The gas is tearing across space at more than 600,000 miles an hour -- fast enough to travel from Earth to the moon in 24 minutes! The star’s surface temperature is estimated to be about 400,000 degrees Fahrenheit, making it one of the hottest known stars in our galaxy. NGC 6302 lies roughly 3,800 light-years away in the constellation Scorpius.

24. Planetary NebulaNGC 6537Red Spider Nebula The Red Spider Nebula is a planetary nebula located in the constellation Sagittarius. The star at the center of the nebula is surrounded by a dust shell making its exact properties hard to determine. The nebula has a prominent two-lobed shape, possibly due to a binary companion or magnetic fields. The central white dwarf, the remaining compact core of the original star, produces a powerful and hot wind blowing with a speed of 300 km/sec, which has generated waves 100 billion kilometers high. These winds are what give this nebula its unique 'spider' shape and also contribute to the expansion of the nebula.

25. Planetary NebulaNGC 6543Cats Eye Nebula The Hubble telescope has made several observations of the Cat’s Eye. This image reveals the full beauty of a bull’s eye pattern of 11 or more concentric rings, or shells, around the dying star. Each ring is actually the edge of a spherical bubble seen projected onto the sky — that is why the nebula appears bright along its outer edge.

26. Planetary NebulaNGC 6751Glowing Eye Nebula The Glowing Eye Nebula is a beautiful example of a classic planetary nebula with complex features. Winds and radiation from the intensely hot central star (140,000 degrees Celsius) have apparently created the nebula’s streamer-like features. Blue regions mark the hottest glowing gas, which forms a roughly circular ring around the central stellar remnant. Orange and red show the locations of cooler gas. The cool gas tends to lie in long streamers pointing away from the central star, and in a surrounding, tattered-looking ring at the outer edge of the nebula.

27. Planetary NebulaNGC 6826The Blinking Eye Nebula NGC 6826's eye-like appearance is marred by two sets of blood-red 'fliers' that lie horizontally across the image. The surrounding faint green 'white' of the eye is believed to be gas that made up almost half of the star's mass for most of its life. The hot remnant star (in the centre of the green oval) drives a fast wind into older material, forming a hot interior bubble which pushes the older gas ahead of it to form a bright rim. NGC 6826 is 2,200 light- years away in the constellation Cygnus.

28. Planetary NebulaNGC 7008Fetus Nebula Observers have long been aware of the unique structure of planetary nebula NGC 7008. Because the central star is so prominent, the original thinking on this nebula’s formation focused around the central star itself. But the motions of the gas are also being observed and a recent study suggest that some of the structures observed are caused by the interaction of central star wind and radiation with preplanetary nebula debris: planets, moons, minor objects and ring and ring arcs. If there are massive enough rings of material surrounding the progenitor and planets in their vicinity, arc rings could be formed. f the rings are viewed pole on when the envelope is detached from the central star, it will interact with the arc ring material and could produce ansae and pedal and garden-hose-shape. NGC 7008 (PK 93+5.2), also known as the Fetus Nebula is located at a distance of 2800 light years in northern Cygnus. .

29. Planetary NebulaNGC 7009Saturn Nebula NGC 7009 has a bright central star at the center of a dark cavity bounded by a football-shaped rim of dense, blue and red gas. The cavity and its rim are trapped inside smoothly-distributed greenish material in the shape of a barrel and comprised of the star's former outer layers. At larger distances, and lying along the long axis of the nebula, a pair of red "ansae", or "handles" appears. Each ansa is joined to the tips of the cavity by a long greenish jet of material. The handles are clouds of low-density gas. NGC 7009 is 1,400 light-years away in the constellation Aquarius.

30. Planetary NebulaNGC 7027 NGC 7027 is one of the brightest planetary nebulae in the sky and can be seen in the constellation of the Cygnus. The cloud of gas and dust is unusually massive as it appears to contain about three times the mass of our Sun.

31. Planetary NebulaNGC 7293Helix Nebula The image shows a fine web of filamentary "bicycle-spoke" features embedded in the colorful red and blue gas ring, which is one of the nearest planetary nebulae to Earth. The tentacles formed when a hot "stellar wind" of gas plowed into colder shells of dust and gas ejected previously by a doomed star.

32. Planetary NebulaNGC 7293Helix Nebula This is a combined image from Spitzer Space Telescope and the Galaxy Evolution Explorer (GALEX). The intense ultraviolet radiation from the white dwarf heats up the expelled layers of gas, which shine brightly in the infrared. GALEX has picked out the ultraviolet light pouring out of this system, shown throughout the nebula in blue, while Spitzer has snagged the detailed infrared signature of the dust and gas in yellow. The white dwarf star itself is a tiny white pinprick right at the center of the nebula. Helix nebula lies 650 light-years away in the constellation of Aquarius.

33. Planetary NebulaPK 164+31.1Jones-Emberson 1 Nebula This bubble of expanding gas is the remnant of the atmosphere of a Sun-like star expelled as its supply of fusion-able core hydrogen became depleted. Visible near the center of the nebula is what remains of the core itself -- a blue-hot white dwarf star. PK 164 +31, also known as Jones-Emberson 1, lies about 1,600 light years away toward the constellation of Lynx.

34. Planetary NebulaRAFGL 2688Egg Nebula Resembling a rippling pool illuminated by underwater lights, the Egg Nebula offers astronomers a special look at the normally invisible dust shells swaddling an aging star. These dust layers, extending over one-tenth of a light-year from the star, have an onionskin structure that forms concentric rings around the star. A thicker dust belt, running almost vertically through the image, blocks off light from the central star. The Egg Nebula is located 3,000 light-years away in the constellation Cygnus.

35. Planetary NebulaOH231.8+4.2Rotten Egg Nebula The object shown in this Hubble image is a remarkable example of a star going through death throes just as it dramatically transforms itself from a normal red giant star into a planetary nebula. This process happens so quickly that such objects are quite rare, even though astronomers believe that most stars like the Sun will eventually go through such a phase. OH231.8+4.2, is seen blowing out gas and dust in two opposite directions. So much dust has been cast off and now surrounds the star that it cannot be seen directly, only its starlight that is reflected off the dust. The flow of gas is very fast, with a velocity up to 450,000 mph (700,000 km/h).