2021-05-18, 15:00: Prof. Philippe Zarka (Observatoire de Paris)
Prof. Philippe Zarka
Observatoire de Paris, France
Perspectives on ground-based observations of Jupiter
Abstract: Radio emissions from Jupiter have been studied for 66 years from the ground and 44 years from space. Although our knowledge has much progressed, the subject is far from exhausted. While the first decades were dominated by exploration, phenomenological studies, determination of the basic emission characteristics (source location, beaming…) and elucidation of the microscopic generation process, a new context (a new reference internal magnetic field model derived from Juno measurements, the ExPRES simulation code…) and new measurements (long-term databases, high time-frequency resolution observations, perspectives for angular resolution in radio, multispectral observations…) allow us to address increasingly precise and complex physical questions (electron acceleration processes, double layers, saturation of the Cyclotron Maser process…).
Today, Jupiter’s magnetosphere and radio emissions can be seen as (1) a nearby astrophysical body to be more fully explored and understood, (2) a unique laboratory for studying low density (low beta) plasma processes on a variety of scales, and (3) the only prototype of an exoplanetary magnetosphere and radiosource that can be studied from the ground for guiding our searches and future studies of exoplanetary radio emissions. Three major low-frequency radiotelescopes involved in the observation of Jupiter are the Nançay Decameter Array, LOFAR, and NenuFAR. The latter two are also involed in exoplanet radio searches.
I will give a brief overview of where we stand and perspectives for ground-based low-frequency radio observations to come.