IC1396 + Sh2-129 in Ha - 2 pane mosaic

[Adreneline]

IC1396 is one of my favourite targets and it seems only appropriate to include its near neighbour Sh2-129 in the image.

Mu Cephei is Herschel's famous "Garnet Star," one of the most deeply-colored stars in the sky situated within the field of view of IC1396. It is a red supergiant star in the constellation Cepheus, and one of the largest and most luminous stars known in the Milky Way.  μ Cep is big enough to show a measurable angular diameter, around 0.02" - equivalent to approximately 1,420 times the size of our Sun. If put in place of the Sun, μ Cep would extend midway between the orbits of Jupiter and Saturn; it could fit over 1 billion suns into its body. Mu Cephei is in the last phase of its life. Although it has certainly stopped internal hydrogen fusion, its exact evolutionary status is uncertain. Most likely, it has begun to fuse helium in its core into carbon. This great star is almost certainly destined to go supernova within the next million years. It will leave behind a vast hydrogen cloud which, for a star as massive as Mu Cephei, may be centered on a black hole. Now that will be worth an imaging session if mankind is still around in a million years!

This is three nights of imaging amounting to 6.5 hours of 180s Ha exposures using a Samyang 135mm (f2.4) and ASI1600 (gain 139, offset 50, -20 degrees), unguided.

Because I don't have a camera rotator there is some cropping to produce a rectangular image but left and right represent the extremes of the mosaic; North is "up".

Calibrated and mosaic assembled in APP. PI used for background extraction and stretch. PS used for minimal noise reduction and contrast enhancement.

Thanks for looking.

Adrian

 

 

[don4l]

I really like this.  I just know that I would have overcooked sh129, and in fact it looks much better like this.

[Adreneline]

14 minutes ago, don4l said:

I really like this.

Thank you! I'm glad you like it. I've seen Sh2-129 imaged on its own and it is very tempting to force the exposure. By adding Sh2-129 to this mosaic of IC1396 I hope I've managed to keep the relative 'brightness' in proportion.

Adrian