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We present a search for exomoons around the Jupiter-like exoplanet Kepler-167e using a NIRSpec JWST transit. Our 60 hr time series clearly reveals the enormous impact of long-term trends in NIRSpec data, specifically a gradual flux drift occurring over each of six 10 hr exposures. We weighed the evidence for exomoons by comparing a planet-only…

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Decomposing the contributions of active galactic nuclei (AGNs) from their host galaxies is essential for identifying AGN-dominated galaxies and accurately deriving key physical properties of both supermassive black holes (SMBHs) and their host galaxies, such as black hole accretion rates, stellar masses, and star formation rates. However, decomposing AGN contributions from multi-wavelength photometry remains challenging…

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The X-ray source in active galactic nuclei (AGNs) is commonly referred to as the corona by analogy to stellar coronae. The similarities between the two suggest that the heating mechanism of AGN coronae is magnetic reconnection—as in cool stars—but this has not yet been directly observed. This work presents the first observational evidence for a…

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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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