Clay weekly context brief for the Astro category (ISO week 2026-W45). Clay tracks publications from the Astro feed list. Below are recent items from this category, each with its source and a short description of what the publication covers when one is available in the source feed. Recent publications: 1. Measuring Precipitable Water Vapor through Dual-Band GPS at Rubin Observatory Source: astro-ph.IM (Instrumentation and Methods for Astrophysics) Link: https://arxiv.org/abs/2610.40363 Precipitable water vapor (PWV) in Earth's atmosphere is a known source of systematic error in ground-based astronomical measurements, particularly at wavelengths greater than 7,000 angstroms. 2. Tidal disruption or plunge: the role of neutron star internal structure in black hole-neutron star mergers Source: astro-ph.HE (High Energy Astrophysical Phenomena) Link: https://arxiv.org/abs/2610.39862 The outcome of black hole--neutron star (BHNS) mergers is studied using a general-relativistic mass-shedding condition in the Kerr spacetime, which determines the tidal-disruption radius from the mass ratio, the black hole (BH) spin, the neutron star (NS) compactness, and the ratio of central to average density, $\eta=\frac{\rho_{c}}{\bar\rho}$. 3. The extragalactic science of the KMOS VVVX-GalCen spectroscopic survey II: Discovery of a galaxy cluster at z = 0.089 behind the Galactic plane Source: astro-ph.GA (Astrophysics of Galaxies) Link: https://arxiv.org/abs/2610.38811 The Zone of Avoidance (ZoA) continues to represent the most significant incompleteness in the extragalactic census of the Local Universe. 4. Tailoring Infra-Red Filters for Global Mapping of Enceladus' Thermal Environment Source: astro-ph.EP (Earth and Planetary Astrophysics) Link: https://arxiv.org/abs/2610.40456 We present the results of an initial study into the feasibility and design of the Enceladus Thermal Mapper (ETM) instrument, designed to provide detailed temperature data for Enceladus, an icy moon of Saturn identified by the Cassini Mission as a prime candidate for astrobiological study due to its subsurface ocean and active cryovolcanism. 5. Efficient GLS map-making and assessment of $1/f$ noise impact for future CMB satellite missions Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics) Link: https://arxiv.org/abs/2610.39581 Time-correlated $1/f$ noise is a major source of large-scale contamination in measurements of the polarized cosmic microwave background (CMB) that can limit sensitivity to primordial $B$ modes. 6. How Common Are Common Envelopes? Quantifying Their Role in Forming Gravitational-Wave Sources Source: astro-ph.SR (Solar and Stellar Astrophysics) Link: https://arxiv.org/abs/2606.05322 A central goal of gravitational-wave astronomy is to use merging binary black hole (BBH), black hole-neutron star (BHNS), and binary neutron star (BNS) systems as fossils to reconstruct the formation and evolution of massive stars across cosmic time. 7. posterior-landscape: morphological feature finding in two-dimensional probability densities Source: astro-ph.IM (Instrumentation and Methods for Astrophysics) Link: https://arxiv.org/abs/2610.40272 We present posterior-landscape, a Python framework to identify and characterize morphological features in two-dimensional probability densities. 8. The first mass peak of merging black holes from core binding energies and jet-driven explosions Source: astro-ph.HE (High Energy Astrophysical Phenomena) Link: https://arxiv.org/abs/2610.39801 We show that the jittering-jets explosion mechanism (JJEM) can qualitatively reproduce the shape of the black hole (BH) mass distribution observed by LIGO-Virgo-KAGRA and quantitatively reproduce the peak around $M_{p1} \simeq 10 M_\odot$. 9. ARRAKIHS: The observability of tidally stripped satellites in a Milky Way-like halo Source: astro-ph.GA (Astrophysics of Galaxies) Link: https://arxiv.org/abs/2610.38779 Deep imaging surveys are revealing increasing numbers of low surface brightness stellar streams around Milky Way-like galaxies. 10. Magma Buoyancy Couples Lunar Mantle Convection and Magmatism: Long-Lasting Mare Volcanism and Radius Change in a 3-D Regional Model Source: astro-ph.EP (Earth and Planetary Astrophysics) Link: https://arxiv.org/abs/2610.39376 To understand the mantle evolution that has caused the observed histories of mare volcanism and radius change of the Moon, we developed a 3-D regional spherical shell mantle convection model with magmatism. 11. Cosmological constraints on extra radiation and early dark energy with lepton asymmetry and varying quark masses Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics) Link: https://arxiv.org/abs/2610.39579 We investigate cosmological constraints on extra radiation and axionlike early dark energy (EDE), allowing primordial lepton asymmetry or light-quark-mass variation during big bang nucleosynthesis (BBN). 12. Confirming candidate self-lensing binary detections with radial velocity measurements Source: astro-ph.SR (Solar and Stellar Astrophysics) Link: https://arxiv.org/abs/2610.30203 Compact objects in approximately edge-on binary orbits with stars are able to produce a self-lensing effect, amplifying light from their companion once per orbit. 13. Model-Based Retrieval of Four Years of JWST/NIRCam Wavefronts Source: astro-ph.IM (Instrumentation and Methods for Astrophysics) Link: https://arxiv.org/abs/2610.40187 The fidelity of data recovered by the James Webb Space Telescope (JWST) depends on precise monitoring of the mirror segments' surfaces and alignment. 14. RAKI: High-Order Alternative Finite Differences for General Relativistic Magnetohydrodynamics Source: astro-ph.HE (High Energy Astrophysical Phenomena) Link: https://arxiv.org/abs/2610.39792 Binary neutron star (BNS) and black hole--neutron star mergers are among the most important multimessenger sources. 15. The coupled evolution of nuclear star clusters and intermediate-mass black holes in a dwarf-galaxy merger Source: astro-ph.GA (Astrophysics of Galaxies) Link: https://arxiv.org/abs/2610.38767 Nuclear star clusters (NSCs) and intermediate-mass black holes (IMBHs) are expected to coexist in low-mass galaxies and might together facilitate the coalescence and growth of IMBHs. 16. The Korean Space Telescope (KST): A Dedicated Space Observatory for the Dark Universe Source: astro-ph.EP (Earth and Planetary Astrophysics) Link: https://arxiv.org/abs/2610.39094 The Korean Space Telescope (KST) is a next-generation 1.4-meter wide-field space observatory, a dedicated probe of the dark sector. 17. Low-variance renoising for weak gravitational lensing shear estimation Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics) Link: https://arxiv.org/abs/2610.39554 The "renoising" noise-bias correction used by Metacalibration and AnaCal adds to every galaxy image an independent noise field with the statistics of the original noise rotated by 90 degrees. 18. Eclipse Properties and Superhump Evolution in the SU UMa-Type Dwarf Nova Z Cha Source: astro-ph.SR (Solar and Stellar Astrophysics) Link: https://arxiv.org/abs/2609.10966 The advent of large-scale time-domain surveys provides both opportunities and challenges for understanding accretion disk evolution in cataclysmic variables (CVs). 19. Identifying narrow-band mutual coupling resonances in SKA-low stations using frequency-independent current basis functions Source: astro-ph.IM (Instrumentation and Methods for Astrophysics) Link: https://arxiv.org/abs/2610.40008 Mutual coupling between closely spaced elements in aperture arrays introduces narrow-band spectral features in the Embedded Element Patterns (EEPs), threatening measurements of the 21-cm power spectrum with instruments such as SKA-low. 20. The Disk Awakens: IXPE's Sequel Observation of GS 1354-64 Suggests Changing-Look Behavior in the Steep-Power-Law State Source: astro-ph.HE (High Energy Astrophysical Phenomena) Link: https://arxiv.org/abs/2610.39384 After decades of only failed transitions, the black hole X-ray binary GS 1354-64 has undergone a complete outburst again. 21. On The Scaling Relations Between Black Holes And The Galaxy/Bulge Mass And Their Connections With The Black Hole Occupation Fraction Source: astro-ph.GA (Astrophysics of Galaxies) Link: https://arxiv.org/abs/2610.38699 We investigate the black hole (BH)--host galaxy scaling relations predicted by the semianalytic model \texttt{FEGA25}, focusing on their dependence on BH mass threshold, galaxy morphology, and redshift, and on their connection with the BH occupation fraction (BHOF). 22. lenscape: Fast, High-resolution $\Delta\chi^2$ Maps of Microlensing Events Source: astro-ph.EP (Earth and Planetary Astrophysics) Link: https://arxiv.org/abs/2610.38764 Planetary microlensing analyses rely on $\Delta\chi^2$ maps across the binary-lens separation $s$ and mass ratio $q$ to locate degenerate solutions and bound parameter uncertainties. 23. A deep learning approach to member identification and mass estimation in galaxy clusters Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics) Link: https://arxiv.org/abs/2610.39546 Accurate dynamical mass estimates of galaxy clusters are essential for studies of cluster formation and evolution and for cosmological applications. 24. The UKIRT M33 Monitoring Project - VII. A 15-year K-band photometric catalogue of long-period variable stars in the central kiloparsec of M33 Source: astro-ph.SR (Solar and Stellar Astrophysics) Link: https://arxiv.org/abs/2610.37591 We present a homogenised K-band photometric catalogue for the central ${\approx}12$ arcmin$^2$ (${\approx}0.9$ kpc$^2$) of the Triangulum spiral galaxy M33, combining four independent PSF-based near-infrared datasets obtained with UKIRT between 2003 and 2018. 25. Preparation of a celestial field for precise VLBI observations of the JUICE spacecraft: a test case of the Venus flyby Source: astro-ph.IM (Instrumentation and Methods for Astrophysics) Link: https://arxiv.org/abs/2610.39925 The Jupiter Icy Moons Explorer mission, launched in 2023, is on its way to the Jovian system, to arrive in 2031. 26. A universal relation predicts the observed reversal of a supernova chirp Source: astro-ph.HE (High Energy Astrophysical Phenomena) Link: https://arxiv.org/abs/2610.39240 Superluminous supernovae, among the brightest stellar explosions, are thought to be powered by newborn magnetars. 27. Chemodynamical Study and Evidence for Hot Compact Companions to Blue Straggler Stars in Berkeley 31 Source: astro-ph.GA (Astrophysics of Galaxies) Link: https://arxiv.org/abs/2610.38654 We present a detailed study of the open cluster Berkeley 31 using Gaia DR3 astrometry, Gaia-ESO Survey DR5.1 spectroscopy, and multi-wavelength photometry. 28. PyMsOfa 2.0: A Pure-Python Implementation of the IAU Standards of Fundamental Astronomy Service Source: astro-ph.EP (Earth and Planetary Astrophysics) Link: https://arxiv.org/abs/2610.38410 Astrometric calculations require authoritative algorithms so that every result is correct and reproducible. 29. Cosmological axion-photon interactions with a nonminimal dark gauge sector Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics) Link: https://arxiv.org/abs/2610.39473 We study the cosmological evolution of radiation and dark radiation with nonminimal axion-photon-dark photon couplings. 30. "Helium Enrichment Law": The Relation Between Helium and Metal Enrichment in Stars in FIRE-3 Simulations of Milky Way-mass Galaxies Source: astro-ph.SR (Solar and Stellar Astrophysics) Link: https://arxiv.org/abs/2610.37529 Helium abundance is a key input to stellar models that are used to infer accurate ages, masses, and compositions for individually resolved stars in the Milky Way (MW), underpinning Galactic archaeology. 31. Robust statistical significance for Gravitational Wave inference Source: astro-ph.IM (Instrumentation and Methods for Astrophysics) Link: https://arxiv.org/abs/2610.39785 The field of gravitational-wave data analysis heavily relies on Bayes factors to make statements about astrophysical effects in events detected by the LIGO-Virgo-KAGRA collaboration. 32. XRISM/Resolve Study of Large Scale Properties in Tycho's Supernova Remnant Source: astro-ph.HE (High Energy Astrophysical Phenomena) Link: https://arxiv.org/abs/2610.39200 Resolve, the microcalorimeter array aboard the X-Ray Imaging and Spectroscopy Mission (XRISM), provides an unprecedented spectral view of Tycho's Supernova Remnant (SNR). Sources in this brief: astro-ph.CO (Cosmology and Nongalactic Astrophysics); astro-ph.EP (Earth and Planetary Astrophysics); astro-ph.GA (Astrophysics of Galaxies); astro-ph.HE (High Energy Astrophysical Phenomena); astro-ph.IM (Instrumentation and Methods for Astrophysics); astro-ph.SR (Solar and Stellar Astrophysics). Selected 32 of 400 available items for this weekly brief.