The high-energy environment of the heavy sub-Earth GJ 367 b indicates likely complete evaporation of its atmosphere
arXiv:2401.17302 · doi:10.1051/0004-6361/202449351
Abstract
The planet GJ 367 b is a recently discovered high-density sub-Earth orbiting an M dwarf star. Its composition was modelled to be predominantly iron with a potential remainder of a hydrogen-helium envelope. Here we report an X-ray detection of this planet's host star for the first time, using data from the spectro-imaging X-ray telescope eROSITA onboard the Spectrum-Roentgen-Gamma (SRG) mission. We characterise the magnetic activity of the host star from the X-ray data and estimate its effects on a potential atmosphere of the planet. We find that despite the very low activity level of the host star the expected mass loss rates, both under core-powered and photoevaporative mass loss regimes, are so high that a potential primordial or outgassed atmosphere would evaporate very quickly. Since the activity level of the host star indicates that the system is several Gigayears old, it is very unlikely that the planet currently still hosts any atmosphere.
7 pages, accepted for publication by A&A, part of the eROSITA DR1 paper splash
References in corpus (26)
- Gaia Data Release 3: Summary of the content and survey properties
- The eROSITA X-ray telescope on SRG
- Atmospheric Escape from Hot Jupiters
- How to Constrain Your M Dwarf: measuring effective temperature, bolometric luminosity, mass, and radius
- Second ROSAT all-sky survey (2RXS) source catalogue
- Roche lobe effects on the atmospheric loss of "Hot Jupiters"
- The SRG X-ray orbital observatory, its telescopes and first scientific results
- The SRG/eROSITA all-sky survey: First X-ray catalogues and data release of the western Galactic hemisphere
- The eROSITA Final Equatorial Depth Survey (eFEDS): The X-ray catalog
- The first XMM-Newton slew survey catalogue: XMMSL1
- The active lives of stars: a complete description of rotation and XUV evolution of F, G, K, and M dwarfs
- When Do Stalled Stars Resume Spinning Down? Advancing Gyrochronology with Ruprecht 147
- The mass of the Mars-sized exoplanet Kepler-138 b from transit timing
- Aeronomical constraints to the minimum mass and maximum radius of hot low-mass planets
- The corona of HD 189733 and its X-ray activity
- GJ 367b: A dense ultra-short period sub-Earth planet transiting a nearby red dwarf star
- GJ 367b is a dark, hot, airless sub-Earth
- A Joint Mass-Radius-Period Distribution of Exoplanets
- First eROSITA study of nearby M dwarfs and the rotation-activity relation in combination with TESS
- Exoplanet X-ray irradiation and evaporation rates with eROSITA
- Effect of mantle oxidation state and escape upon the evolution of Earth's magma ocean atmosphere
- Company for the ultra-high density, ultra-short period sub-Earth GJ 367 b: discovery of two additional low-mass planets at 11.5 and 34 days
- New insights into the rotational evolution of near-solar age stars from the open cluster M67
- The shared evaporation history of three sub-Neptunes spanning the radius-period valley of a Hyades star
- Complete X-ray census of Mdwarfs in the solar Neighborhood I. GJ 745 AB: Coronal-hole Stars in the 10 pc Sample
- A Distinct Population of Small Planets: Sub-Earths