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We report the discovery and characterization of the multiplanetary system around TOI-4311, a K dwarf kinematically between the Galactic thick disc and Hercules stream. TOI-4311 hosts an ultra-short-period super-Earth (P$sim$0.99 d, $1.376^{+0.077}_{-0.080}$ R$_{oplus }$) and a longer period sub-Neptune (P$sim$15 d, $2.47^{+0.12}_{-0.11}$ R$_{oplus }$) that was first detected in the Transiting Exoplanet Survey Satellite photometry.…

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Context. High-mass star-forming regions are rich in complex organic molecules (COMs), which are carbon-bearing species with at least six atoms. Their formation pathways remain debated. The ALMA evolutionary study of high-mass protocluster formation in the GALaxy (ALMAGAL) survey provides a unique opportunity to probe this chemical complexity in a large statistical significant sample of high-mass…

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Context. The K2-138 system consists of a K-dwarf transited by six planets in the sub-Neptune regime, with radii ranging from 1.5 to 3.4 R⊕ and orbital periods of between 2.3 and 42 days. The five innermost planets form a chain of zero-order three-body resonances, while the outermost planet is suspected to be linked to the…

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The supermassive binary system, η Carinae, is experiencing enormous wind-driven mass loss at a rate unparalleled in the rest of the Galaxy. Their wind─wind collision (WWC) continuously produces shock heated, X-ray-emitting plasmas. The XRISM X-ray observatory observed the system in 2023 and 2024 when the X-ray emission began to increase toward periastron passage in 2025.…

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The atmospheres of hot rocky exoplanets are among the first primary targets of the James Webb Space Telescope (JWST). Interpreting their atmospheric spectra requires understanding the link between silicate lava compositions and overlying atmospheres. We investigate the sensitivity of simulated emission spectra of dry lava planets to variations in oxide abundances in silicate melt. Our…

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We present the first high-resolution spectroscopy of the black hole high-mass X-ray binary Cygnus X-1 with XRISM, including orbital-phase-resolved analyses and tentative evidence of short-term variability in the Fe K band on second timescales. Using data from the Performance Verification phase in 2024 April, we analyzed spectral variability across orbital phases with the Resolve microcalorimeter…

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