We present a statistical analysis of the ages and metallicities of triple stellar systems that are known to host exoplanets. With controversial cases disregarded, so far 27 of those systems […]
metallicity
![Super-Earth occurrence for Kepler (black circles) and K2 (gray circles), TESS data assuming all candidates are real (teal square), and 99.7% confidence intervals to calculate the upper limits for TESS data assuming all candidates are false positives (teal triangles) as a function of metallicity. The [-0.25,-0.5] bin occurrence rates are offset horizontally for visual clarity. The best-fit power-law trend line for the Kepler and K2 data (yellow) is displayed and extrapolated to [Fe/H]= -0.75 showing the 1-σ uncertainties (Zink et al. 2023). We show the combined best-fit exponential trend line for Kepler, K2, and TESS (purple) (eq. 6) including the 1-σ uncertainties. Each metallicity bin is indicated by gray dashed lines. Within the [-0.75,-1] bin, there is insufficient data to further constrain the super-Earth occurrence rate as a function of metallicity (denoted by the gray hatched region). -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/07/The-First-Evidence-of-a-Host.png?resize=1200%2C720&ssl=1)
Posted inAstrochemistry, Astrogeology, Exoplanets, -moons, -comets, Press Release
The First Evidence of a Host Star Metallicity Cut-off In The Formation of Super-Earth Planets
Planet formation is expected to be severely limited in disks of low metallicity, owing to both the small solid mass reservoir and the low opacity accelerating the disk gas dissipation.
Posted inAstrochemistry, Astronomy & Telescopes, Imaging & Spectroscopy, Interstellar, Status Report
Central Oxygen Abundances In The Spiral Galaxies Of The MaNGA Survey: Galaxies With Central Starbursts
We examine whether there are deviations of the local central oxygen abundances in spiral galaxies from the general metallicity gradients.
![Best-fit free retrieval of the JWST NIRSpec and HST WFC3 data for WASP-77A b. The coloured regions show the individual contribution of three species (H2O, CO, and TiO) and Collision Induced Absorption (CIA), while the inset shows the 1, 2, and 3σ confidence intervals for the retrieved temperature-pressure (T − p) profile. These three species are detected in the HST and JWST data, allowing us to place constraints on elemental ratios for this atmosphere. The best-fit T − p profile has a positive lapse rate (i.e, no evidence for a thermal inversion) in the pressure region probed by our observations (p ∈ [105 , 100] Pa). -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/02/MeasuringTracers.png?resize=1200%2C719&ssl=1)
Posted inAtmospheres, Climate, Weather, Exoplanets, -moons, -comets, Status Report, Stellar Cartography
Measuring Tracers of Planet Formation in the Atmosphere of WASP-77A b: Sub-stellar O/H and C/H ratios, with a stellar C/O ratio and a potentially Super-stellar Ti/H ratio
We present a comprehensive atmospheric retrieval study of the hot Jupiter WASP-77A b using eclipse observations from the Hubble Space Telescope (HST) and JWST.
Posted inAstrogeology, Astronomy & Telescopes, Exoplanets, -moons, -comets, Status Report
A Revisit Of The Mass-Metallicity Trends In Transiting Exoplanets
The two prevailing planet formation scenarios, core-accretion and disk instability, predict distinct planetary mass-metallicity relations. Yet, the detection of this trend remains challenging due to inadequate data on planet atmosphere […]
Posted inAstrochemistry, Imaging & Spectroscopy, Interstellar, Status Report
Can Pre-supernova Winds From Massive Stars Enrich The Interstellar Medium With Nitrogen At High Redshift?
Understanding the nucleosynthetic origin of nitrogen and the evolution of the N/O ratio in the interstellar medium is crucial for a comprehensive picture of galaxy chemical evolution at high-redshift because […]
Posted inAstrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release
Early Release Science Of The Exoplanet WASP-39b With JWST NIRCam
Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories.