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The Object M27 was discovered by Charles Messier in 1764. The Dumbbell Nebula Messier 27 (M27, NGC 6853) is perhaps the finest planetary nebula in the sky, and was the first planetary nebula ever discovered. The name "Dumb-bell" goes back to the description by John Herschel, who also compared it to a "double-headed shot." This planetary nebula is certainly the most impressive object of its kind in the sky, as the angular diameter of the luminous body is nearly 6 arc minutes, with a faint halo extending out to over 15', half the apparent diameter of the Moon. It is also among the brightest, being at most a little less luminous with its estimated apparent visual magnitude 7.4 than the brightest, the Helix Nebula NGC 7293 in Aquarius, with 7.3, which however has a much lower surface brightness because of its larger size. The central star of M27 is quite bright at magnitude 13.5, and an extremely hot bluish dwarf at about 85,000 K (spectral type of O7). K.M. Cudworth of the Yerkes Observatory found that it probably has a faint (magnitude 17) yellow companion at 6.5" in position angle 214 deg (Burnham). As for most planetary nebulae, the distance of M27 (and thus true dimension and intrinsic luminosity) is not very well known. Hynes gives about 800, Kenneth Glyn Jones 975, Mallas/Kreimer 1250 light years, while other existing estimates range from 490 to 3500 light years. Currently, investigations with the Hubble Space Telescope are under work to determine a more reliable and accurate value for the distance of the Dumbbell Nebula. Adopting an average value of 1200 light years, the intrinsic luminosity of the gaseous nebula is about 100 times that of the Sun (with an absolute magnitude of about -0.5) while the star is at about +6 (1/3 of the Sun) and the companion at +9..9.5 (nearly 100 times fainter than the Sun), all in the visual light part of the electromagnetic spectrum. That the nebula is so much brighter than the star shows that the star emits primarily highly energetic radiation of the non-visible part of the electro-magnetic spectrum, which is absorbed by exciting the nebula's gas, and re-emitted by the nebula, at last to a good part in the visible light. Actually, as for almost all planetary nebulae, most of the visible light is even emitted in one spectral line only, in the green light at 5007 Angstroms. About 2 degrees to the West of M27 is inconspicuous open cluster NGC 6830, containing about 20-30 widely scattered stars; this cluster is about 5500 light years distant. Imager: James Edward Keeler Object: M27/NGC6853 Name: Dumbbell Nebula Type: Planetary Nebula Constellation: Vulpecula Site: Lick Observatory, Mount Hamilton, California Date: 1899 Telescope: Crossley 36" Reflector Optical System: Newtonian Reflector Mount: Other German Equatorial Mount Type: German Equatorial Camera: Not Known Camera Type: Not Known Details 31st July 1899; 3 hours exposure; Orientation South at Top; 36" Crossley Reflector, Lick Observatory, Mount Hamilton, California         Image: M27 the ‘Dumbbell Nebula’ is without doubt one of the most beautiful of all astronomical objects, with its predominant ‘teal’ colour tinged with splashes bright red at its edges. It is one of the first targets any budding astrophotographer attempts to capture. Not surprisingly it was a popular subject for pioneering astrophotographers who first imaged it over a century ago. Of all the early photographs of M27, James Keeler’s image of it taken in 1899 is by far the most magnificent. Although taken over 110 years ago using glass photographic plates, it is still to this day a remarkable image. It perfectly captures not only the ‘Dumbbell’ shape but also the fainter nebulosity that surrounds its central regions. In quality, it is comparable to that achieved using a ‘modest’ modern astrophotography CCD.         Imager: James Edward Keeler was a 19th Century American astronomer and a pioneer of spectroscopic astrophotography. He was born on the 10th September 1857 at La Salle, Illinois, United States. The family moved to Mayport, Florida in 1869, where the young Keeler first became interested in Astronomy. In 1875-77 he founded the Mayport Astronomical Society and used its meager equipment (a two inch achromatic refractor) to observe stars, planets and nebulae. He enrolled at John Hopkins University late in 1877 and graduated in 1881 after majoring in Physics and German. Shortly before receiving his degree he was appointed as an assistant astronomer at the Allegheny Observatory in Pittsburg. In 1885 was appointed to the staff of the new Lick Observatory at Mount Hamilton, California, and for a time he was the only astronomer there. Keeler was the first to observe the gap in Saturn's rings now known as the Encke’s Gap, using the 36-inch refractor at Lick Observatory on 7 January 1888. This feature had been named after Johann Encke, who had observed a much broader variation in the brightness of the A Ring. Keeler's work was acknowledged, when the second major gap in the A Ring, discovered by the Voyager probe, was named the Keeler Gap in his honour. He left Lick in May 1891 after being appointed director of the University of Pittsburgh's Allegheny Observatory in 1891. It was whilst at Allegheny that Keeler took up Photography as one of the means to make use of the meager resources the Observatory had, as opposed to the wealth of equipment available at Lick. In 1895, his spectroscopic study of the rings of Saturn revealed that different parts of the rings reflect light with different Doppler shifts, due to their different rates of orbit around Saturn. This was the first observational confirmation of the theory of James Clerk Maxwell that the rings are made up of countless small objects, each orbiting Saturn at its own rate. These observations were made with a spectrograph attached to the 13-inch Fitz-Clark refracting telescope at Allegheny Observatory. He returned to Lick Observatory as its director in 1898. In the brief time that was left to him, Keeler did not just concentrate on administrative matters he actively participated in research, and in particular using the 36” Crossley Reflector (built by Andre Ainslie Common in England) to capture some of the most magnificent images ever taken of Comets, Galaxies, Nebulae and Star Clusters. The objects photographed included, the Pleiades (M45), Trifid Nebula (M20), the Great Orion Nebula (M42), Brooks Comet of 1898, Hind’s Variable Nebula in Taurus (NGC 1555) and many of the brighter Herschel objects. In 1908 the results of Keeler’s work were posthumously published in “Photographs of Nebulae and Clusters Made with the Crossley Reflector, Publications of the Lick Observatory Volume VIII”. A number of the photographs included were taken after Keeler’s death. In 1899 he was awarded the Henry Draper medal for his work on Saturn’s rings. James Edward Keeler died shortly afterwards on the 12th August 1900 due to a stroke whilst recovering from a severe cold. He had married in 1891 and left a widow and two children. His ashes were interred in a crypt at the base of the 31-inch Keeler Memorial telescope at the Allegheny Observatory. In addition to the Keeler Gap in Saturn's rings, craters on Mars and the Moon are named in his honour, as is the asteroid 2261 Keeler.