Each Pochven system has one C729 reverse static wormhole with its own unique spawn zone. These zones are are shown in the maps here (they sometimes partially overlap).
     Proximity filaments activated in a given Pochven system will punt you to a random one of its spawn zone systems.
All static wormholes have a zone of systems they can link to (e.g. "every LS system" or "all C1s").
A normal static respawns in its host system and its K162 (the generic "other side" of all wormholes") appears in a random system of its zone once certain conditions are met.
A reverse static, by contrast, respawns outside its host system—somewhere in its zone—and its K162 shows up in the host system if the conditions are met.
Pochven has 3 other reverse-statics (two to JS and one to the Dronelands) and Thera has 3 to KS (L031, M164, and T458).

There are 1028 known systems with Jove Observatories, but these are player-reported (get in touch if you find one not on the list).
They're fairly evenly-distributed around KS, varying from ~14 to ~22% coverage.
Unidentified aka Drifter wormholes spawn in 1024 of these systems (the four JOs in Pochven seem to have been deactivated when Pochven was created).