The Eruptive Prominence of August 7, 1950.

The eruptive prominence of August 7, 1950, is shown to be associated with an active sunspot group and plage area. Spectra of the prominence indicate that the large opening in the prominence prior to and during the eruption was due to the absence of Ha radiation and was not a result of wave-length displacement caused by high radial velocity. The velocities of the measured features varied in a similar way with time and ranged from 10 km/sec to an average maximum of 155 km/sec. A burst of 200 Mc solar radio noise occurred when the ascending prominence reached a height of 285,000 km.