Comparative Magnetospheric Science: Bringing Planets to Low-Mass Stars
When
Where
Dr. Melodie Kao
Researcher
Lowell Observatory
As brown dwarf masses and temperatures approach planetary thresholds, their stellar-like flare activity gradually transitions to more planet-like auroral and radiation belt activity. These overlapping magnetic activity regimes position brown dwarfs as unique, powerful, and accessible laboratories that probe star-planet interaction and exoplanet magnetospheric physics. For instance, JWST recently detected methane emission from an unbound Y dwarf indicating a temperature inversion in its upper atmosphere. One possible explanation is that substantial auroral heating is taking place. Indeed, the upper atmospheres of Solar System planets display heating that solar insolation alone cannot explain. Instead, they appear to experience substantial auroral heating.
In this forward-looking talk, I will discuss the status of the search for radio aurorae from Y dwarfs. I will present a new proposed solution to the long-standing mystery of Uranus' dramatically cooling thermosphere and discuss implications for the ongoing effort to detect signatures of aurorae from exoplanets. Finally, we will explore current proof-of-concept efforts to showcase how exoplanet auroral emissions can probe stellar wind properties. These discussions will take place within the framework of a new concept for a flagship low frequency radio array in space, the Great Observatory at Long Wavelengths (GO-LoW).
Host: Dr. Sukrit Ranjan