postscript file     pdf file

This article introduces the reprint of the landmark paper ``The Five-Minute Oscillations on the Solar Surface'' by R. K. Ulrich, ApJ, 162, 993 (1970). In this paper, Ulrich hypothesized-contrary to the then prevailing opinion-that the oscillatory phenomena seen on the surface of the sun were the result of waves propagating in the solar interior and derived the key prediction that led to the field of helioseismology.