New Whole Earth Telescope observations of CD-24 7599: Steps towards δ Scuti star seismology

92 h of new Whole Earth Telescope observations have been acquired for the δ Scuti star CD-24 7599. All the seven pulsation modes reported by Handler et al. are confirmed. However, significant amplitude variations which are not caused by beating of closely spaced frequencies occurred within two years. Analysing the combined data of both WET runs, we detect six further pulsation modes, bringing the total number up to 13. We also examine our data for high-frequency pulsations similar to those exhibited by rapidly oscillating Ap stars, but we do not find convincing evidence for variability in this frequency domain. © 1997 RAS.