HD 209458 b is the first exoplanet on which an atmosphere was detected. Since then, its atmosphere has been investigated using multiple telescopes and instruments. However, many of its atmospheric […]
metallicity
Posted inAstrochemistry, Astrogeology, Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report
BOWIE-ALIGN: Sub-stellar Metallicity and Carbon Depletion in the Aligned TrES-4b with JWST NIRSpec Transmission Spectroscopy
The formation and migration history of a planet is expected to be imprinted in its atmosphere, in particular its carbon-to-oxygen (C/O) ratio and metallicity.
Posted inAstrogeology, Exoplanets, -moons, -comets, Status Report
Planets And Planetesimals At Cosmic Dawn: Vortices As Planetary Nurseries
Low-mass, metal-enriched stars were likely present as early as cosmic dawn. In this work, we investigate whether these stars could have hosted planets in their protoplanetary disks.
Posted inAstronomy & Telescopes, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Press Release
Small And Large Planets Have Significantly Different Upbringings
The shape of a planet’s orbit is one of its fundamental properties, along with its size and distance from its host star. Earth has a nearly circular orbit, but some […]
![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)
Posted inAstrogeology, Exoplanets, -moons, -comets, Status Report, Stellar Cartography
Short-Period Small Planets with High Mutual Inclinations are more Common around Metal-Rich Stars
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, […]
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 […]