Artist's illustration of the magnetic field around a gas giant (c) Astrobiology Center

Future ground-based radio telescopes are expected to be capable of detecting radio signals from an extrasolar gas giant. The radio emission from a gas giant is related to interactions between high-energy, charged particles, especially, electrons, and a planetary magnetic field. The planetary magnetic field can be generated and maintained by a dynamo in an electrically-conducting fluid inside a planet, e.g., the metallic hydrogen region in a gas giant. This study has investigated the relationship between the magnetic field strength of an extrasolar gas giant and its elusive interior structure. The strength of a magnetic field is insensitive to the interior structure, specifically, the inner core, for a hot Jupiter, whereas the emergence of the magnetic field and its strength inside a hot Saturn are closely related to the existence of an inner core. This research was published in the Astrophysical Journal on Feb.26, 2021.

Paper Info:

Journal:The Astrophysical Journal
Title:The Linkage between the Core Mass and the Magnetic Field of an Extrasolar Giant Planet from Future Radio Observations
Auther : Yasunori Hori   (Astrobiology Center / National Astronomical Observatory of Japan)