Alniyat (Sigma Scorpii) and associated Hydrogen Nebula

Alniyat is classified as a Beta Cephei variable. Alniyat is part of a double-lined spectroscopic binary system.
It is a main sequence star of the spectral type B1 V with a mass of 11.9 solar masses and a radius 9 times that of
the Sun. It shines with around 16,000 solar luminosities. The two stars complete an orbit every 33 days.

The Sigma Sorpii Nebula is part of the beautiful region known as the Rho Ophiuchus Nebula complex,
seen here in my wider field image from several years ago :



Main Image details

Orion Optics UK AG12 F3.8
Starlightxpress TRIUS PRO-814 Midi Combi PRO Blue Edition incl. CFW & OAG unit
FLI Atlas Focuser
HaRGB = 555, 72, 66, 84min total 13hrs*
Astronomik Deep-Sky LRGB filters
-20C chip temp, flats used but no dark frames.
Focal length 1120mm
Image scale 0.68"/pix
Guide Camera: Starlightxpress Lodestar PRO

Comments
Data collected over two nights 20 & 28 June 2025, in good to acceptable seeing (1.6" - 2.1")**

**NB: No drizzle guide, upscaling, Blur Exterminator or other AI based sharpening, was used on this
data, this is the native 0.68"/pix image scale, using just traditional Richardson Lucy deconvolution.

Seeing (FWHM) quality at Eagleview:
Excellent: <1.6"
Good: 1.6" - 1.9"
Acceptable: 2.0" - 2.3"
Poor: >2.3"
Most common FWHM value: 1.6"/1.7"

Taken from Eagleview Observatory:

https://pbase.com/strongmanmike2002/eagleview_observatory

Equipment setup:

https://pbase.com/strongmanmike2002/image/173097781/original

Some links to equipment used to take this image:

Sidereal Trading

https://www.siderealtrading.com.au/

StarlightXpress CCD Cameras and imaging equipment

http://www.sxccd.com/products

Finger Lakes Instrumentation CCD cameras:

http://www.flicamera.com/

Gerd Neumann and Astronomik filters:

http://www.astronomik.com/en/home

http://www.gerdneumann.net/

MSB Software & Astroart Camera control and Image processing software

http://www.msb-astroart.com/