in alpha, look somewhere in the middle of the radioactive cloud, i have convieniently forgot the coordinates

i dont remember the coords exactly either, but if you switch to the minable area on your navmap, go above and between the two gas mining areas.. you'll start to see a ton of junked corsair ships and a few nomads will probably attack you.
note: even with the best shield, the nomad cannons will drain you fast.. bring batteries

Is there one in Gamma? I know there's one in Alpha, between that "poison planet" and the other Omicron jump holes (that's North of the holes, for all you non-explorers out there. Havent' found one in Gamme, but there is an unlabeled jump hole from Theta to Alpha (not labeled on the Theta side), just fyi.

Sector F4 in Omicron Alpha...
But I've found nothing in the Unknown system...

Man the unknown system in Omicron Gamma is freaky. It looks like a giant pipe, with some weird weird amoeba planet at then end, and some star way off in the distance that apparently doesn't burn you up when you get close to it. Also the monkey and robot planets are weird in that they both have the planet info of Junyo in the Kusari system, and I even caught one of the robots saying he works for the Order. Obviously it was an unfinished system, as there are a lot of glitches with it (repair button comes up but doesn't work for robot planet?). But anyway the background of that system really is forboding, makes me feel like I shouldn't be there, not to mention those weird spike thingys floating around and the heavy heavy yellow "dust" cluster floating around in space. Anyway, kinda cool easter eggs tho.