Jupiter Observations using the EAARO High Frequency Detector
We will be observing Jupiter’s storms using the EAARO High Frequency Detector. The complex relationship between the gas giant planet and its volcanic moon Io is not completely understood, but we do know these bodies work together to produce "radio noise storms" as they pirouette through space. The emissions we can hear are often referred to as decametric noise storms, because the waves are tens of meters long.
Jupiter is the largest and closest to the sun of the "gas giant" planets in our solar system. Like the sun, Jupiter is composed primarily of hydrogen. If Jupiter had been several magnitudes larger during its formation, the core of the planet would have been under sufficient pressure to induce nuclear fusion and our solar system would have had two stars instead of one. As it is, the hydrogen gas within the deeper reaches of the planet (there is no solid surface) is compressed into a "metallic" state where electrons become freely shared by the proton nuclei. Above this inner region lies an "atmosphere" of hydrogen and other gases. Clouds of methane, ammonia, ammonium, hydrosulphide, and water form complex stormy bands which encircle the planet. The Great Red Spot is the most famous feature of Jupiter. It is actually a long duration storm, which because of its tremendous size, has a life expectancy of hundreds of years. From our vantage point, even through a 2" telescope, we see Jupiter as a banded sphere flanked by as many as four tiny but bright moons. The innermost moon, Io, is of interest to us as radio observers of the planet.
Early observations of Jupiter at the microwave wavelength of 3 cm corresponded to a blackbody (broadband thermal emission) of 150 degrees Kelvin. Indeed, that is the approximate temperature of Jupiter's cloud tops. Subsequent observations at lower frequencies began to point to extraordinarily high energies which could not be explained as thermal in nature. These high energy emissions, which occur below 4O.5 Mhz, are the result of a phenomena called synchrotron radiation. This type of radio emission occurs when charged particles, usually electrons, are accelerated to extremely high velocities in a magnetic field. The electrons thus accelerated shed excess energy in the form of radio and sometimes even light frequency waves. In Jupiter's case the magnetic field is provided by the planet itself. The noise storms occur when the inner moon ,Io , passes through major flux lines of magnetic field in such a way that the emissions are essentially beamed in our direction.
The EAARO HF detector will be used to observe radio signals emitted from Jupiter in the HF part of the radio spectrum.
The EAARO HF Detector will observe Jupiter’s radio emissions and log the signal strength against time.