We review the existing distance estimates to the black hole X-ray binary Swift J1727.8─1613, present new radio and near-UV spectra to update the distance constraints, and discuss the accuracies and caveats of the associated methodologies. We use line-of-sight H I absorption spectra captured using the MeerKAT radio telescope to estimate a maximum

Context. We analyze the optical variability of the flat-spectrum radio quasar (FSRQ) Ton 599 using BVRI photometry from the Whole Earth Blazar Telescope (WEBT) collaboration (2011─2023), complemented by photometric and spectroscopic data from the Steward Observatory monitoring program. Aims. We aim to characterize short- and long-term optical

Non-uniformity plays an important role for MHD waves. For a uniform plasma of infinite extent the MHD waves can be subdivided in two classes with distinct properties. The first class contains the Alfvén waves. The Alfvén waves are incompressible and propagate parallel vorticity. They do not have a parallel component of displacement, they do not

It is relatively rare for gas giant planets to have resonant or near-resonant companions, but these systems are particularly useful for constraining planet formation and migration models. In this study, we examine Kepler-1624b, a sub-Saturn orbiting an M dwarf that was previously found to exhibit transit timing variations (TTVs) with an amplitude

Two leading hypotheses for hot Jupiter migration are disk migration and high-eccentricity migration (HEM). Stellar obliquity is commonly used to distinguish them, as high obliquity often accompanies HEM. However, low obliquity does not guarantee disk migration, due to possible spin─orbit realignment or coplanar HEM. Seeking a proxy for disk

Context. One of the primary goals of Galactic Archaeology is to reconstruct the Milky Way's accretion history. To achieve this, significant efforts have been dedicated to identifying signatures of past accretion events. In particular, the study of the integrals of motion (IoM) space has proven to be highly insightful for uncovering these ancient