Planetary and Solar Radio Emission at 11 Meters Wavelength

Observations are described of radio emissions from the Sun, Jupiter, and Venus during 1956 and early 1957 at a wavelength of 11 meters. Records are presented of solar 11-meter radiation at the time of a large (importance 3) flare on August 31, 1956, and during other periods of solar activity. The effect of scintillation on records of radio stars also is illustrated. A number of records of impulsive radiation from Jupiter at both slow and fast recorder speeds is shown. The radiation is of a bursty or intermittent nature which can be classified into two main types: one which may persist for several seconds and produces a rumbling sound in the loudspeaker and another which is of very short duration (10 milliseconds or less) and produces a cracking or clicking sound. Many of the short pulses consist of distinct pairs or triplets which fall into two main groups, one having pulse separations of about one-quarter second and the other, pulse separations of about one tenth this value. An echo mechanism to explain the multiple pulses is postulated and observed trends in pulse separation compared to those expected with such a mechanism. The stronger Jupiter pulses indicate a peak radiated radio power at the source of the order of 10 kilowatts per cps bandwidth.