* Astro-Physics RH305, SBIG STXL 16200, Frames:H-Alpha: 44×600″ + RGB: 45×600″, total exposure: 14,8 hours.
* Image acquisition by Eric Coles and Mel Helm.
* Image processing by Ruben Barbosa
Listening to the soundtrack of the musical Phantom of the Opera (Andrew Lloyd Webber’s) or Phantom of the Opera (Sarah Brightman & Antonio Banderas).
“In sleep he sang to me
In dreams he came
That voice which calls to me
And speaks my name
And do I dream again
For now I find
The Phantom of the Opera is there
Inside my mind”
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.