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Visual Magnitude: 7.8 (nebula)
Size: 35.0 min X 30.0 min
Distance: 9,400 light years
Discoverer: Edward Emerson Barnard, 1881

Visual Description: NGC 281 in Cassiopeia is a bit of an enigma: Sky Atlas 2000.0 (second edn), Uranometria 2000.0, and the Millennium Star Arias all depict it as an open cluster and a nebula, and it is listed as such in NGC 2000.0, the Observing Handbook and Catalogue of Deep-Sky Objects, the Deep-Sky Field Guide, and Sky Catalogue 2000.0 (Vol. 2). But, as Brent A. Archinal and Steven J. Hynes note in their book Star Clusters, NGC 281 is not a star cluster, but rather the nebulosity involved with the star cluster 1C 1590. The hidden treasure you seek, then, is NGC 281 (the nebula). 1C 1590 (the cluster) is a visual bonus - like the inlaid gems and precious stones that adorn the Taj Mahal's majestic white marble edifice.

Edward Emerson Barnard  (1857-1923) discovered NGC 281 visually on November 26, 1881. Recently married and caring for: his invalid mother, Barnard was, at the time trying to strengthen his financial situation.  During the day he worked at Poole's Pho­tograph Gallery in Nashville, Tennessee. At night, he used a 5-inch Byrne refractor to scan the skies for comets. He was also trying his hand at raising chickens. The discovery of NGC 281 came while he was feverishly in quest of the US $200 Warner prize; in 1881 H. H. Warner (a wealthy patron of astron­omy from Rochester, New York) announced that he would award a gold medal and US $200 in cash for the first American discov­erer of each new comet. Barnard quickly sniffed out a road to success. On the evening of September 17,1881, he discovered an 8th-magnitude comet low in the western sky. Although the comet did not become a visual spectical, it did bring him his first Warner prize - part of which he used to purchase a tiny plot of land in Nashville, on which he then financed a home. And it was from this new home "on a beautiful rising ground” with a clear horizon, that he discovered the new nebula. 

The discovery of NGC 281, of course, was a financial disappointment; new comets, not new nebulae, paid. No matter, Barnard went on to discover 16 comets, five of which earned him Warner prizes - enough to pay off the mortgage of his new home, which he named “Comet House." Although new nebula did not bring any financial rewards, they still intrigued him, especially since no one could yet explain their nature.Despite the great sky surveys conducted by the Herschels and other celestial treasure hunters over the last century and more, nebula visible in small telescopes were still being discovered. "While some nebulae could easily be recognized by their fantastic forms,” William Sheehan writes in The Immortal Fire Within: The Life and Work of Edward Emerson Barnard, "the majority were, at least in the 5-inch telescope Barnard used, 'roundish patches of foggy matter, extremely like comets in appearance’.” NGC 281 is no exception; with its curious Parabolic shape, the 7th-magnitude glow looks very much like the head of a new comet just beginning to grow a tail. The question is how could such an object, one that is visible in binoculars today, have gone unnoticed for so long? The answer is twofold.  First, the nebula is large (35' x 30'), larger than the full Moon, and its surface brightness is low (23.6), so the great William Herschel hadn't much of a chance to spy it in his narrow 15' field of view (which is what he used during his sweeps). Second, it's pos­sible that comet hunters prior to Barnard did not encounter NGC 281 because it lies outside the comet "haystack" - that region of sky (within 60º of the Sun) where comets are most likely to be discovered by visual observers using small telescopes. But Barnard did not follow the adopted routine of his predecessors; he believed the entire sky was the comet seeker's domain. The comet seeker, he said, "must examine every portion of [the sky] time and again... Every­thing is interesting and numberless objects are beautiful in the extreme. There is noth­ing commonplace in the sky."

Seeing the ghostly form of NGC 281 among the rich stellar folds of the Cassiopeia Milky Way must have bordered on the spir­itual for Barnard, a man of strong religious conviction. Of all things, Barnard was espe­cially fond of the Milky Way, the "jewel house of the Maker." When we sweep there, he said, "our soul mounts up, up to that won­derful Creator, and we adore the hand that scattered the jewels of heaven so lavishly in this one vast region. No pen, can describe the wonderful scene that the swinging tube reveals as it sweeps among that vast starry array of suns." Yes, NGC 281 was a financial disappointment, but how hard is it to imag­ine that the discovery of this object in this man's most revered corridor of the heavens would be anything but spiritually uplifting.

Here is a complex tapestry of glowing gas forming the backdrop to a tattered curtain of obscuring dust. The entire eastern front of the nebula appears in turmoil. Bulbous masses of dark and light seemingly bat­tle for prominence. It is as if all manner of supernatural shapes and forms are try­ing to materialize from the bubbling sur­face of a witch's brew. Among the tumult, needle-thin protuberances and dense neb­ulous spires jut from the cloud \vith three-dimensional clarity; some sport at their tips tiny black dots - the mystifying Bok Glob­ules. These dense knots of dust and gas are the black pools into which we peer help­lessly, to dream our dreams of creation, for these are the secret birth sites of new stars. How Barnard's heart would have fluttered had he lived to see such an image. It would have been like looking into the mind of his Creator.

Today, we know NGC 281 is an emission nebula - a vast cloud of ionized hydrogen gas in the Perseus arm the Milky Way. It is excited by a compact trapezium-like, cluster of OB stars (IC1590), which, some recent studies show, formed only about 3.5 million years ago. If this is true, its stars are a bit older than those in the Orion Nebula (1 million years) an much younger than the age of our Sun (4.5 billion year).  The cluster's brightest member - the O5 star HD 5005 (a triple star that shines at magnitude 9.0) - contributes most of the light to the nebula. The glowing gas and dark obscuring clouds are actually part or larger complex of atomic and molecular clouds forming an 880-light-year-wide ring around NGC 281, which is expanding away from the nebula at 22 kilometers per second. The entire complex was probably first formed by supernovae explosions, which triggered subsequent episodes of star formation, including those ongoing today.

Telescope: Takahashi TSA102 APO Refractor
Focal Length: 610 mm at f5.98 with reducer / flattener
Mount: Takahashi NJP 160
Camera: SBIG ST10XME
Exposure:  15 8-minute exposures through a hydrogen alpha filter
Other: SBIG ST402ME

Image Processing: CCDStack and Photoshop CS2

Astro Images

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Copyright(c) 2007 Doug Sanqunetti. All rights reserved