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Designations:
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IC342, Caldwell C5
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Object Type:
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Mixed Spiral Galaxy (SABcd)
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Constellation:
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Camelopardalis
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03 hr 46.8 min
(Epoch 2000) |
+68° 06 min (Epoch 2000)
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8.4 (SB 15.0)
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Size:
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16.1 x 15.5 arcminutes
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Distance:
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13 million light years
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Discoverer:
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William F. Denning
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IC342 is a moderately open, clumpy, low surface-brightness spiral whose
classification suggests a barred
galaxy
in transition. William F. Denning first sped the
galaxy's sharp
central glow and amorphous halo around 1890. But the spiral nature of the "nebula" remained unnoticed
until Edwin P. Hubble and Milton L. Humason noted, in 1934, the
galaxy's
beautiful pinwheel pattern on plates
taken from California's Mount Wilson.
In Shape and form IC342 looks similar to the open-faced spirals M74 in Pisces and M101 in Ursa Major. Quantitatively, too, the three galaxies share comparable visual characteristics. IC 342's apparent diameter of 16 arc-minutes is about midway between that of M74 ( 10 arc-minutes ) and M101 ( 29 arc-minutes ). IC 342's surface brightness (15.0) matches those of M74 (14.4) and M101 (14.8). These data clearly suggest that IC 342 should have been within the visual range of Messier and his contemporaries. Why then was it not noticed until the late 19th century? perhaps its anonymity resulted from the combination of IC 342's far-northern declination (+68 degrees, an unlikely region for comet hunting), low surface brightness, and isolation ( being in a region devoid of any especially bright stars or conspicuous asterisms). Unfortunately for us, IC 342 lies only 11° above the plane of our galaxy, where dense gas and dust dim the extragalactic spiral's light by nearly 3 magnitudes. IC 342 forms a group with some large and many dwarf galaxies, the so-called Maffei 1 group, or IC 342 group, or sometimes called IC 342/Maffei group. It is one of two dominating members of that group, the other being elliptical galaxy Maffei 1, which is even more obscured and was thus only discovered in 1968. http://seds.org/~spider/spider/LG/i0342.html |
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Telescope:
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Focal Length:
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1200 mm
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Mount:
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Camera
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Guider:
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Exposures:
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24 8-minute exposures ( 3 hours and 12 minutes )
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Location:
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Twin Lakes Star Party - western Kentucky
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Software:
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CCDSoft for image acquisition, processed with CCDStack and Photoshop CS2
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Image Automation:
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