Energy Dissipation in the Upper Atmospheres of Trappist-1 Planets

Abstract

We present a method to quantify the upper-limit of the energy transmitted from the intense stellar wind to the upper atmospheres of three of the Trappist-1 planets (e, f, and g). We use a formalism that treats the system as two electromagnetic regions, where the efficiency of the energy transmission between one region (the stellar wind at the planetary orbits) to the other (the planetary ionospheres) depends on the relation between the conductances and impedances of the two regions. Since the energy flux of the stellar wind is very high at these planetary orbits, we find that for the case of high transmission efficiency (when the conductances and impedances are close in magnitude), the energy dissipation in the upper planetary atmospheres is also very large. On average, the Ohmic energy can reach $0.5-1W/m^2$, about 1\% of the stellar irradiance and 5-15 times the EUV irradiance. Here, using constant values for the ionospheric conductance, we demonstrate that the stellar wind energy could potentially drive large atmospheric heating in terrestrial planets, as well as in hot jupiters. More detailed calculations are needed to assess the ionospheric conductance and to determine more accurately the amount of heating the stellar wind can drive in close-orbit planets.

arXiv comment6 pages, 1 table, 2 figures, accepted to ApJ Letters

References in corpus (22)

• Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1
• A seven-planet resonant chain in TRAPPIST-1
• Inflating Hot Jupiters With Ohmic Dissipation
• Assessing the Habitability of the TRAPPIST-1 System Using a 3D Climate Model
• Three-Dimensional Atmospheric Circulation Models of HD 189733b and HD 209458b with Consistent Magnetic Drag and Ohmic Dissipation
• Formation of TRAPPIST-1 and other compact systems
• Is Proxima Centauri b habitable? -- A study of atmospheric loss
• Strong XUV irradiation of the Earth-sized exoplanets orbiting the ultracool dwarf TRAPPIST-1
• The Space Weather of Proxima Centauri b
• Magnetic Effects in Hot Jupiter Atmospheres
• On the Age of the TRAPPIST-1 System
• Magnetohydrodynamic Simulations of the Atmosphere of HD 209458b
• Temporal evolution of the high-energy irradiation and water content of TRAPPIST-1 exoplanets
• The Threatening Environment of the TRAPPIST-1 Planets
• Convergent Migration Renders TRAPPIST-1 Long-lived
• The Interaction of Venus-like, M-dwarf Planets with the Stellar Wind of Their Host Star
• Enhanced interplanetary panspermia in the TRAPPIST-1 system
• The Stellar Activity of TRAPPIST-1 and Consequences for the Planetary Atmospheres
• The dehydration of water worlds via atmospheric losses
• Electrodynamics on extrasolar giant planets
• Plausible Compositions of the Seven TRAPPIST-1 Planets Using Long-term Dynamical Simulations
• Comparative Climates of TRAPPIST-1 planetary system: results from a simple climate-vegetation model

Cited by in corpus (15)

• The Revolution Revolution: magnetic morphology driven spin-down
• Atmospheric Escape Processes and Planetary Atmospheric Evolution
• TESS's first planet: a super-Earth transiting the naked-eye star $\pi$ Mensae
• New rotation period measurements for M dwarfs in the southern hemisphere: an abundance of slowly rotating, fully convective stars
• The First Habitable Zone Earth-sized Planet from TESS. I: Validation of the TOI-700 System
• Physical constraints for the evolution of life on exoplanets
• Simulating the Space Weather in the AU Mic System: Stellar Winds and Extreme Coronal Mass Ejections
• Modeling a Carrington-scale Stellar Superflare and Coronal Mass Ejection from ${\kappa }^{1}Cet$
• One Year in the Life of Young Suns: Data Constrained Corona-Wind Model of kappa1 Ceti
• Stellar Winds Drive Strong Variations in Exoplanet Evaporative Outflows and Transit Absorption Signatures
• The TRAPPIST-1 JWST Community Initiative
• An Earth-like stellar wind environment for Proxima Centauri c
• The Space Environment and Atmospheric Joule Heating of the Habitable Zone Exoplanet TOI700-d
• Towards a holistic magnetic braking model from the evolution of cataclysmic variables to stellar spin-down -- I: the spin-down of fully convective M-dwarfs
• L 98-59: a Benchmark System of Small Planets for Future Atmospheric Characterization