A planet whose broken moon forms an asteroid belt, shown by Wesley Crusher to Salia of Daled IV as a holodeck image during their brief romance.
Rousseau V is a planet seen as a holodeck recreation in the Next Generation episode The Dauphin.
Wesley Crusher, taken with the young passenger Salia, wants to show her some of the sights she will never visit once she becomes ruler of Daled IV. He takes her to the holodeck and calls up the asteroid belt of Rousseau V, the remains of a shattered moon, where neutrino clouds make a sound like music.
Salia is delighted, and the visit deepens their attachment. It also sharpens the conflict with her guardian Anya, who regards everything aboard the Enterprise as a threat.