The European Radio Astronomy Club frequencies, the ionosphere is opaque. Here, two targets are possible: the Sun with its solar flares or Jupiter, which is also a very strong radio source, together with the moon Io, which is a very powerful natural radio wave transmitter. When Jupiter, Io and the Earth are aligned, it is possible to hear this radio source very clearly. The European Radio Astronomy Club The European Radio Astronomy club (ERAC) is Europe's only group coordinating the work of radio astronomers to jointly use radio waves to study the universe at radio wavelengths. It was founded in 1995 by Peter Wright, who
Atmospheric wave Atmospheric wave An atmospheric wave is a periodic disturbance in the fields of atmospheric variables (like surface pressure or geopotential height, temperature, or wind velocity) which may either propagate ("traveling wave") or not ("standing wave"). Atmospheric waves range in spatial and temporal scale from large-scale planetary waves (Rossby waves) to minute sound waves. Atmospheric waves with periods which are harmonics of 1 solar day (e.g. 24 hours, 12 hours, 8 hours... etc.) are known as atmospheric tides. The mechanism for the forcing of the wave, for example the generation of the initial or prolonged disturbance in the atmospheric variables, can