Space Weather & Heliophysics

Radio Signatures of Star-Planet Interactions, Exoplanets, and Space Weather

By Keith Cowing

Status Report

astro-ph.EP

September 25, 2024

Filed under astro-ph.EP, atmosphere, climate, exoplanet, heliophysics, magnetic activity, radiation, space weather

Radio Signatures of Star-Planet Interactions, Exoplanets, and Space Weather — Schematic representation of a CME and the radio dynamic spectrum of the event that shows Type II and III bursts. The Type II burst is produced in the coronal shock front, as represented by the blue region emanating from the red star in the left panel. The magnetic reconnection event that is allowing mass to escape the magnetosphere of the star is shown as the yellow region. Type III bursts are produced on open field lines surrounding the magnetic reconnection event. Some structure and higher frequency harmonic emission is evident in and around the Type II burst in the right panel. The dynamic spectrum is in total intensity. — astro-ph.EP

Radio detections of stellar systems provide a window onto stellar magnetic activity and the space weather conditions of extrasolar planets, information that is difficult to attain at other wavelengths.

There have been recent advances observing auroral emissions from radio-bright low-mass stars and exoplanets largely due to the maturation of low-frequency radio instruments and the plethora of wide-field radio surveys. To guide us in placing these recent results in context, we introduce the foremost local analogues for the field: Solar bursts and the aurorae found on Jupiter.

We detail how radio bursts associated with stellar flares are foundational to the study of stellar coronae, and time-resolved radio dynamic spectra offers one of the best prospects of detecting and characterising coronal mass ejections from other stars. We highlight the prospects of directly detecting coherent radio emission from exoplanetary magnetospheres, and early tentative results.

We bridge this discussion to the field of brown dwarf radio emission, in which their larger and stronger magnetospheres are amenable to detailed study with current instruments. Bright, coherent radio emission is also predicted from magnetic interactions between stars and close-in planets. We discuss the underlying physics of these interactions and implications of recent provisional detections for exoplanet characterisation.

We conclude with an overview of outstanding questions in theory of stellar, star-planet interaction, and exoplanet radio emission, and the prospects of future facilities in answering them.

J. R. Callingham, B. J. S. Pope, R. D. Kavanagh, S. Bellotti, S. Daley-Yates, M. Damasso, J.-M. Grießmeier, M. Güdel, M. Günther, M. M. Kao, B. Klein, S. Mahadevan, J. Morin, J. D. Nichols, R. A. Osten, M. Pérez-Torres, J. S. Pineda, J. Rigney, J. Saur, G. Stefánsson, J. D. Turner, H.Vedantham, A. A. Vidotto, J. Villadsen, P. Zarka

Comments: Accepted to Nature Astronomy. The manuscript is designed to be a primer for new doctoral students and scholars to the field of radio stars and exoplanets. 36 pages, 3 figures
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:2409.15507 [astro-ph.EP] (or arXiv:2409.15507v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2409.15507
Focus to learn more
Submission history
From: Joseph Callingham Dr
[v1] Mon, 23 Sep 2024 19:52:44 UTC (3,705 KB)
https://arxiv.org/abs/2409.15507
Astrobiology

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

Follow on Twitter