1. if u talk about the "unknown" systems, check Omicron Alpha and Omicron Gamma for their entrance-jumpholes. 2. no. unfortunately not. 3. the hardest missions u can find in Sovetskaya. 4. Sigma 17
(Quote from LynRyu)only 2 "unknown" systems are in the map. but there are some more. but they are tricky. the way in is not always the same way out. the entrances to these systems u'll find in the 2 shown "unknown" systems.