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Location/ Date: |
Eggersdorf, GER / 05.+27. January 2017 |
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Telescope/ Lens |
10" f/4 ONTC Newton |
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Mount: |
Celestron CGE GPS |
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Camera: |
Atik 383L+ |
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Exposure time: |
18x 1800" Astronomik Ha 6nm 8x 300" je Astronomik RGB |
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Total exposure: |
11 hours |
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Description: |
SH2-173 is a HII region with a diameter of 77 light years, approximately 8800 light-years away from Earth. It is located in the constellation of Cassiopeia in the Perseus arm, on of the main arms of our Milky Way. Due to its resemblance to the mask main charakter of Andrew Lloyd Webbers musical the nebual is often called the "Phantom of the Opera" nebula.
SH2-173 is about 3 degrees north of Caph (β-Cas, mag 2,27) and was estimated to be about 600,000 to 1,000,000 years old by Cichowolski. The emission nebula contains 7 bright CAS-OB5 stars and is primarily ionized by the only O-star BD+6039. It turned out that SH2-173 is still expanding at a speed of about 16km/s. SH2-173 is harbouring 46 young star objects. |