The night sky turns around Polaris once every 23 h 56 m, like a record on a turntable. Here a needle sits on the meridian above the pole, and every star that sweeps under it plays a note. The trails are a long exposure building up as it spins.
The needle works like a music-box comb. Stars close to Polaris sit in the inner grooves and play low notes. Stars out near the celestial equator play high notes. Polaris itself rings once per turn, the lowest note on the record.
Each star's B–V colour index sets its timbre. Hot blue-white stars like Vega ring like glass. Cool orange and red giants like Arcturus and Betelgeuse sound softer and warmer.
Brighter stars play louder and ring longer. Move the brightness slider toward 5.5 to bring in fainter stars and fill the record, or toward 2 to hear only the brightest.