The script spelling for this planet was "Rosseau V",  however several other sources, including the Star Trek Encyclopedia (4th ed., vol. 2, p. 239), as well as the episode's closed captioning, spelled it as "Rousseau V."
In the same script, rather than neutrino clouds forming the harmonic resonance, it was stated that the harmonic resonance occurred after "the orbits of the moons [became] synchronous."
Visual Effects Supervisor Dan Curry used lava rocks he found in the buildings supply for this scene. He was very careful sorting the right rocks out. (TNG Season 2 DVD special feature "Departmental Briefing Year Two: Memorable Missions - The Dauphin")