produced granulation datasets clearly show oscillation modes around mhz power spectrum sun around modes maximum power using data golf virgo spm instruments aboard solar heliospheric observatory low degree modes l show clear comb like pattern regular spacing soho colour scale logarithmic saturated one hundredth maximum power signal make modes visible low frequency region dominated signal granulation angular degree increases individual mode frequencies converge onto clear ridges corresponding
Natural science Space science Stellar astrophysics Helioseismology