Shock waves generated by the intense solar flare of 1972, August 7, 15:00 UT

The dynamic radio spectrum of the class 3B solar flare of 1972, August 7, 15: 00 UT, over the band 10 to 2000 MHz is examined. Type II and type IV bursts in the spectrum are interpreted in terms of a piston-driven shock, which appeared to be travelling at a velocity of about 1500 km s^?1 and which generated pulsations in the band 100 to 200 MHz as it passed through the corona. The progress of the shock through the interplanetary plasma was subsequently monitored by Malitson et al. with radio equipment covering the band 0.03 to 2.6 MHz on the IMP-6 satellite.