This always bothered me and I finally got round to fixing it, texture seams on the Mars sky are gone and I will be adding more as I find them (If MEM can actually find them) it was very fiddly and time consuming but I think worth the effort. The texture is based on the one from ALOT so is 4k and can be installed with that.

I use the 2k limit in ALOT installer so these screenshots will be at vanilla resolution, choose 4k and of course they will look better than this.