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Powerful ionized accretion disk winds are often observed during episodic outbursts in Galactic black hole transients. Among those X-ray absorbers, Fe XXVI doublet structure (Lyα1+Lyα2 with ∼20 eV apart) has a unique potential to better probe the underlying physical nature of the wind, i.e., density and kinematics. We demonstrate, based on a physically motivated magnetic…

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A crucial chemical link between stars and their orbiting exoplanets is thought to exist. If universal, this connection could affect the formation and evolution of all planets. Therefore, this potential vital link needs testing by characterizing exoplanets around chemically-diverse stars. We present the discovery of two planets orbiting the metal-poor, kinematic thick-disc K-dwarf TOI-2345. TOI-2345…

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Substellar companions such as exoplanets and brown dwarfs exhibit changes in brightness arising from top-of-atmosphere inhomogeneities, providing insights into their atmospheric structure and dynamics. This variability can be measured in the light curves of high-contrast companions from the ground by combining differential spectrophotometric monitoring techniques with high-contrast imaging. However, ground-based observations are sensitive to the…

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Eclipse mapping is a powerful tool for measuring 3D profiles of exoplanet atmospheres. To date, only JWST has been capable of widely applying this technique, but as a general observatory, it is too time-limited to conduct population-level mapping studies. Ariel, on the other hand, is a dedicated exoplanet mission set to observe 1000 transiting exoplanets,…

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GRS 1915+105 was the stellar-mass black hole that best reproduced key phenomena that are also observed in type 1 active galactic nuclei (AGNs). In recent years, however, it has evolved to resemble a type 2 or Compton-thick AGN. Herein we report on the first XRISM observation of GRS 1915+105. The high-resolution Resolve calorimeter spectrum reveals…

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We present the X-ray analysis of seven local compact elliptical galaxies (cEGs), selected for their morphological resemblance to high-redshift red nuggets. As likely descendants of the red nugget population, cEGs offer a unique window into the early Universe, enabling the study of early galaxy evolution and the interplay between black holes, stellar bulges, and dark…

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