This panorama is created using several Affinity Photo tools. Star Brushes, Pattern Layer, Equirectangular Projection.
1. Document with a 2:1 ratio
2. Pattern Layer
3. Seamless stars texture (two layers)
4. Equirectangular Projection
5. Replacing distorted parts (poles)
The original 4K texture was rescaled to 2K, using the "Nearest Neighbour" method.
To view the finished result in 3d space, see Blender file: Space_360.blend
This diagram explains the reason for the 2:1 aspect ratio:
Recent. Made it in designer desktop and finished in publisher, because only publisher supports hyperlinks. Made using Organika Design Kit for Affinity Designer. Made my process easy and fun. @Frankentoon, thank you!