M101 or NGC5457 is a face-on spiral galaxy distanced 21 million light-years away in the constellation Ursa Major, first discovered by Pierre Méchain on March 27, 1781, and communicated to Charles Messier who verified its position for inclusion in the Messier Catalogue as one of its final entries.
It is an Sc type galaxy with several H II regions, that in deep pictures count up to 3000; these regions, in which stars form, are ionized by large numbers of extremely bright and hot young stars.
M101 shows an asymmetrical structure due to the tidal forces from interactions with its companion galaxies. [Wiki]
In this annotated version, apart from the most known NGC objects, there are 74 galaxies in this small field of less than 3 squared degrees.... |
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| Optic |
SW ED80 + 0,85 Reducer/Flattener |
| Camera |
Atik 383L+ |
| Filters |
Baader L, R, G, B 36mm |
| Mount |
NEQ6
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Guide
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SW 70/500 with AlCCD5
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Frame center
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RA 14:03:55 DEC 54:26:36 J2000
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Date
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20th April 2015
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Site
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Pian dell Armà, Italian Alps
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| Exposures
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L - 18x600s Bin 1x1 @-10°C
R - 9x300s Bin 2x2
G - 9x300s Bin 2x2
B - 9x300s Bin 2x2
Integration time - 5h 15m
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Notes
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First light of the setup and first LRGB processing.
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