![Relations between mutual inclination and stellar metallicity and stellar mass after sample control. Left: stellar metallicity vs. mutual inclination plot for a subsample of 78 systems selected to minimize the influence of stellar mass. Right: stellar mass vs. mutual inclination plot for a subsample of 81 systems selected to minimize the influence of stellar metallicity. Unlike [Fe/H] vs. ∆i, the correlation between stellar mass and ∆i is not statistically significant in our sample, although we cannot completely rule out such a correlation. See Section 5 for more details. -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2025/02/Short-Period-Small-Planets.png?resize=1200%2C720&ssl=1)
We present a correlation between the stellar metallicities and the mutual inclinations of multi-planet systems hosting short-period small planets (a/Rs<12, Rp<4Re). We analyzed 89 multi-planet systems discovered by Kepler, K2, […]
metallicity
Posted inAstrochemistry, Astrogeology, Brown Dwarfs, Exoplanets, -moons, -comets, Interstellar, Status Report
Early Accretion of Large Amounts of Solids for Directly-Imaged Exoplanets
As the number of planetary mass objects (PMOs, ⪅13 MJupiter) at wider separation (⪆10 AU) grows, there is emerging evidence that they form differently from their higher-mass brown-dwarf (BD) counterparts.
Posted inAstronomy & Telescopes, Exoplanets, -moons, -comets, Status Report, Stellar Cartography
A Data-Driven M Dwarf Model and Detailed Abundances for ∼17,000 M Dwarfs in SDSS-V
The cool temperatures of M dwarf atmospheres enable complex molecular chemistry, making robust characterization of M dwarf compositions a long-standing challenge.
Posted inAstronomy & Telescopes, Brown Dwarfs, Exoplanets, -moons, -comets, Exploration Gear & Tech, Gas Giants, Status Report, Stellar Cartography
The TESS-Keck Survey XXIV: Outer Giants May be More Prevalent in the Presence of Inner Small Planets
We present the results of the Distant Giants Survey, a three-year radial velocity (RV) campaign to search for wide-separation giant planets orbiting Sun-like stars known to host an inner transiting […]
Posted inAstrochemistry, Astronomy & Telescopes, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Status Report
Investigating Chemical Variations Between Interstellar Gas Clouds In The Solar Neighbourhood
The interstellar medium (ISM) is a fundamental component of the Milky Way. Studying its chemical composition and the level of its chemical diversity gives us insight into the evolution of […]
![Illustration similar to that of Fig. 2 in Nimmo et al. (2020), demonstrating the sensitivity of core convection to changing concentrations of radiogenic elements (relative to the terrestrial amount), see Nimmo et al. (2020) for details on model parameters. Color scaled to represent net entropy production from radiogenic heating, with the black region representing negative production (no dynamo). Dashed red line represents the regime at [Eu/α]=0.08 where a dynamo failure lasting > 100 Myr first begins. Solid black lines represent contours of constant mantle temperature. astro-ph.SR](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/12/Distribution-of-Europium-in-The-Milky-Way-Disk.png?resize=1200%2C720&ssl=1)
Posted inAstrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biophysics, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Origin & Evolution of Life, Radiation, Status Report
Distribution of Europium in The Milky Way Disk; Its Connection to Planetary Habitability and The Source of The R-Process
The energy provided in the radioactive decay of thorium (Th) and uranium (U) isotopes, embedded in planetary mantles, sustains geodynamics important for surface habitability such as the generation of a […]
Posted inAstrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Imaging & Spectroscopy, Interstellar, Status Report
Determining The Absolute Chemical Abundance of Nitrogen and Sulfur in the Quasar Outflow of 3C298
Context. Quasar outflows are key players in the feedback processes that influence the evolution of galaxies and the intergalactic medium. The chemical abundance of these outflows provides crucial insights into […]
![Top panel: Comparison of our determined [Fe/H] values (blue line) against the reported metallicity from Mann et al. (2015), Passegger et al. (2019), Maldonado et al. (2020), Marfil et al. (2021) and Cristofari et al. (2022). The red shaded area represents the typical distribution of M dwarfs metallicity from SDSS DR18 (Almeida et al. 2023). Bottom panel: Residuals are plotted to compare the median metallicity values from all referenced studies against each individual work. All measurements are consistent. -- astro-ph.SR](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/11/Chemical-Fingerprints-of-M-Dwarfs.png?resize=1200%2C717&ssl=1)
Posted inAstrochemistry, Astronomy & Telescopes, Imaging & Spectroscopy, Press Release, Stellar Cartography
Chemical Fingerprints of M Dwarfs: High-Resolution Spectroscopy on 31 M Dwarfs with SPIRou
We extend the methodology introduced by Jahandar et al. (2024) to determine the effective temperature and chemical abundances of 31 slowly-rotating solar neighborhood M dwarfs (M1-M5) using high-resolution spectra from […]
Posted inAstrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Imaging & Spectroscopy, Status Report
A Study of Polycyclic Aromatic Hydrocarbon Emission in 30 Dor as seen by JWST
Polycyclic aromatic hydrocarbons (PAHs) are responsible for strong mid-IR emission features near star-forming regions. It is well known that low-metallicity environments exhibit weaker PAH emission, but it is not clear […]
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gas Giants, Habitable Zones, Ice Giant, Imaging & Spectroscopy, Neptune, Status Report
Effects of Planetary Parameters on Disequilibrium Chemistry in Irradiated Planetary Atmospheres: From Gas Giants to Sub-Neptunes
A primary goal of characterizing exoplanet atmospheres is to constrain planetary bulk properties, such as their metallicity, C/O ratio, and intrinsic heat. However, there are significant uncertainties in many aspects […]