Sazuna/UAT_keywords huggingface dataset:
AI-enhanced Citizen Science Discovery of an Active Asteroid: (410590) 2008 GB140. We report the discovery of cometary activity emanating from Main-belt asteroid 410590 (2008 GB140), a finding facilitated, for the first time, by an artificial intelligence (AI) assistant. The assistant, TailNet, is a prototype we designed to enhance volunteer efforts of our Citizen Science project Active Asteroids, a NASA Partner program hosted on the Zooniverse platform. Our follow-up investigation revealed eight Dark Energy Camera images showing 2008 GB140 with a tail spanning UT 2023 April 23–UT 2023 July 3, when the object was inbound to perihelion. We classify 2008 GB140 as an active asteroid and a candidate Main-belt comet (MBC)—a main-belt asteroid that undergoes volatile sublimation-driven activity. Notably, 2008 GB140 is presently near perihelion, thus the object is a prime target for follow-up observations to further characterize its activity.

Keywords: Comet tails, Convolutional neural networks, Asteroids, Comae
2016 UU121: An Active Asteroid Discovery via AI-enhanced Citizen Science. We report the discovery of an active asteroid, 2016 UU121, for the first time via artificial intelligence-enhanced classification, informed by our NASA Partner program Active Asteroids, a Citizen Science project hosted on the Zooniverse platform. The early version of our deep neural network, TailNet, identified potential activity associated with 2016 UU121 in 40 Dark Energy Camera (DECam) images from UT 2021 September 10 to 11. The discovery was vetted and confirmed by our Active Asteroids core science team. In total, 66 DECam images of this object showed clear activity in the form of a tail. 2016 UU121 has a Tisserand parameter with respect to Jupiter of 3.161, thus we classify the object as an active asteroid. Moreover, the activity occurred near perihelion, so 2016 UU121 is also a candidate Main-belt comet.

Keywords: Asteroids, Comet tails, Convolutional neural networks, Comet dynamics, Short period comets, Asteroid belt
An Upper Limit to Differential Magnification Effects in Strongly Gravitationally Lensed Galaxies. Differential magnification is now well-known to distort the spectral energy distributions of strongly gravitationally lensed galaxies. However, that does not mean that any distortions are possible. Here I prove an analytic upper bound to differential magnification effects. For example, a thermal or sub-thermal CO ladder cannot be made to appear super-thermal just from gravitational lensing, and the Balmer decrement emission line ratio Hα:Hβ cannot reduce below the case B prediction just from differential magnification. In general, if a physical model of a galaxy predicts upper and/or lower bounds to an emission line ratio, then those bounds also apply to the differentially magnified strongly gravitationally lensed case. This applies not just for velocity-integrated emission lines, but also for the line emission in any rest-frame velocity interval.

Keywords: Surveys, Gravitational lensing
TOI-6883.01: A Single-transit Planet Candidate Detected from TESS. A new candidate exoplanet, proposed in ExoFOP by authors, it was promoted from TIC 393818343 to TOI-6883.01 at coordinates R.A.(J2000)20:41:10.01 decl.(J2000) + 3:38:17.87 in the Delphinus constellation and its distance is (93.73 ± 0.35) pc from Earth. The target star is a Sun-type having G0 class according to Skiff spectral classification and it has photometric magnitude V(Johnson) = 9.5 mag. We analyzed the transit light curve using Transit Exoplanet Survey Satellite's ExoMAST tool, and evaluated the Lightcurve Analysis Tool for Transiting Exoplanets-report by excluding false positives, studying the background, satellite and centroid motion, and analyzing the pixels in sector 55 to define the source goodness. The candidate exoplanet transit has a duration of TD = 3.957 hr, Depth = 0.1196% and mid-transit time occurs at TBJD = 2811.24. Only one event was observed, so the orbital period cannot be evaluated.

Keywords: Light curves, Exoplanet astronomy, Transit photometry, Exoplanets
Scientific Impact of Novel Instrumentation: The Case of MUSE. In the process of transforming science cases into a viable and affordable design for a novel instrument, there is the problem of how to gauge their scientific impact, especially when they end up in competing top level requirements that can be incompatible with each other. This research note presents a case study for scientific impact of the integral field spectrograph MUSE in terms of number of refereed publications from 2014 to 2024 as a figure of merit, broken down by different research areas. The analysis is based on the Basic ESO Publication Statistics service and NASA's Astrophysics Data System.

Keywords: Astronomical instrumentation
Hidden Companions to Intermediate-mass Stars. XVI. Unveiling a 41,300 au Companion to the Very Eccentric Binary Zeta Boötis. Zeta Boötis is a nearby 2.2 M ⊙ + 2.2 M ⊙ 125 yr period visual binary distinguished by its very high eccentricity e ≈ 0.98. Here we report that HIP 71759 is a very wide 1.65 M ⊙ companion to ζ Boo at a projected separation $\rho =13\buildrel{\,\prime}\over{.} 3\leftrightarrow {\rm{41,300}}\,\mathrm{au}$ , an association that has been missed in previous wide binary searches. We estimate a projected velocity difference Δv 2D = 0.86 ± 0.20 km s‑1 compared to the Newtonian 2D escape velocity v esc,2D = 0.5 km s‑1. We propose that the triple system is gravitationally bound and that it was once much more compact, with the outer companion exciting high amplitude Kozai–Lidov eccentricity oscillations in ζ Boo as it also migrated outwards by removing energy from the inner binary. The Galactic tidal field eventually shut off the triple interaction, freezing the e ≈ 0.98 eccentricity of ζ Boo.

Keywords: Trinary stars, Elliptical orbits, A stars
Imaging Spectropolarimetry—A New Observing Mode on the Hubble Space Telescope's Advanced Camera for Surveys. Imaging spectropolarimetry is a new observing mode on the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope (HST) that was commissioned in Cycle 30 and is available to HST observers starting in Cycle 31 (i.e., from 2023). It is a technique that is accessible from ground-based observatories, but the superb spatial resolution afforded by HST/ACS combined with the slitless nature of HST/ACS grism spectroscopy opens up the possibility of studying polarized extended emission in a way that is not currently possible even with Adaptive Optics facilities on the ground. This mode could help to study interesting targets including (but not limited to) QSOs, active galactic nucleus and Radio Galaxies, ISM Dust Properties, Pre-Planetary Nebulae, Proto-Planetary and Debris Disks, Supernovae/Supernova Remnants, and solar system objects. This research note presents the preliminary results from the calibration programs used to calibrate imaging spectropolarimetry on HST/ACS.

Keywords: Hubble Space Telescope, Astronomical techniques, Spectropolarimetry, Polarimetry
A Possible Meteoric Fall in Cabeza la Vaca (Spain) in 1970 January. We recover a report in the "HOY" regional newspaper about a presumed meteorite fall near Cabeza la Vaca, Spain. The report details observable effects like a crater, uprooted tree, and a destroyed fence. While the exact date is unknown, it likely occurred within a week of 1970 January 27. The report lacks the crater size specification. This research note underscores the potential significance of the reported meteorite fall, encouraging further investigation.

Keywords: Meteorites
The Far Ultraviolet Light Curve of 78 Vir (A2p SrCrEu). All IUE spectra obtained shortwards of 2000 Å with the SWP camera are used to construct a far-ultraviolet (FUV) light curve at 1500 Å for 78 Vir over its rotational period. Setting an arbitrary phase 0.00 for the first spectrum recorded on 1987 May 10, the minimum and maximum occur respectively near phases 0.20–0.25 and 0.60–0.70. The Fine Error Sensor counts, which measure the brightness near the V band, vary in phase with the FUV flux, which is the opposite situation to that observed in another cool Ap star, 21 Com.

Keywords: Ap stars, Chemically peculiar stars
Galactic Archeology with Luminous Red Giant Oscillations in Gaia DR3 Photometry. Asteroseismology has significantly advanced the field of Galactic archeology, providing essential insights into the formation and evolution of our Galaxy. Here we present an asteroseismic analysis of 103 luminous red giant stars that were observed by Gaia in our Galaxy and the Large Magellanic Cloud. Leveraging a period–luminosity–amplitude relationship determined using data from the OGLE mission, we measure distances to these stars of up to 100 kpc, probing distances more than a factor of 2 beyond where Gaia parallaxes can be measured accurately. We have determined distance uncertainties of 8% or better for 80% of the stars in our sample and reduced known distance uncertainties for stars in this sample by more than a factor of 2 on average. Applying this approach to future Gaia data releases can provide more precise and accurate distances and constrain fundamental properties for 10,000+ stars across our Galaxy.

Keywords: Stellar oscillations, Galactic archaeology, Asteroseismology, Variable stars
Modeling the Light Curve of HD 222925's Progenitor Kilonova. The leading theory for heavy element nucleosynthesis is that a majority of isotopes heavier than iron are formed in neutron star mergers (NSMs), visible through the kilonovae that proceed them. In this work, we derive the potential kilonova light curve associated with the elemental abundances of the "gold standard" metal-poor star HD 222925, which is thought to be enriched by a single NSM. Previous work explores which initial kilonova conditions best match the elemental abundances in HD 222925 and finds two main solutions: either the ejecta is highly constrained, or the underlying nuclear microphysics model is incomplete. We construct the light curves for these two cases in hopes of using kilonova to break this degeneracy. We find that our merger models produce light curves that are observationally too alike to robustly distinguish between the two valid models, offering little hope for constraining kilonova ejecta or the behavior of neutron-rich nuclei.

Keywords: Neutron stars, R-process, Gravitational wave sources, Stellar mergers
A Radio Galaxy Gravitational Lens in the COSMOS-Web Survey. COSMOS 5914+1219 is a radio galaxy that is gravitationally lensing a background star-forming galaxy. We use a total of eight Hubble Space Telescope and JWST images to model the radio source host galaxy as a bulge plus disk system and fit the photometry from the optical through mid-infrared. We find best-fitting photometric redshifts of ≈1.65 for the radio galaxy and ≈4 for the lensed galaxy. We confirm a high stellar mass for the lens of 3.3 ± 0.2 × 1011 M ⊙ compared to a mass enclosed by the Einstein Ring of 1.6 ± 0.1 × 1012 M ⊙ and a star formation rate (SFR) of 340 ± 150 M ⊙ yr‑1. For the lensed galaxy, we estimate a stellar mass of 9.9 ± 1.7 M ⊙/μ and a SFR of 150 ± 55 M ⊙/μ, where μ is the amount of magnification via lensing.

Keywords: Radio active galactic nuclei, Gravitational lensing
Quasars versus Microquasars: Scaling and Particle Acceleration. Quasars and microquasars both contain accreting black holes and power nonthermal double radio sources, but differ in more than their scales: Quasars are proportionally much more efficient accelerators of energetic electrons. The radio luminosity of the double radio sources associated with quasars, reflecting the long-time average of the particle acceleration power, is often 1%–30% of the quasar's bolometric luminosity; in microquasars the fraction is ≲10‑5. This may be explained by the scaling of accretion disk parameters with the black hole mass.

Keywords: Supermassive black holes, Stellar mass black holes, Quasars
The Infrared Variability of V1647 Ori over 26 yr with Spitzer, (NEO)WISE, and ISO. Outbursts from young Class 0 protostars are now being detected using 3─5 μm light curves assembled from Spitzer and WISE/NEOWISE photometry. For comparison, we present a 4─8 μm light curve of the erupting, more evolved protostar V1647 Ori (HOPS 388), assembled from photometry obtained with the ISOCAM camera on ISO, the IRAC camera on Spitzer, and from WISE and NEOWISE. Covering 26 yr, this light curve spans the longest available time interval from infrared space-based telescopes capable of separating individual young stellar objects in nearby molecular clouds. This curve does not include a two year interval where the visible-light photometry shows a large drop in brightness. In the case of V1647 Ori, we find that the increase in brightness (3.1 mag) and duration (16 yr) are similar to infrared (3─5 μm) outbursts found toward Class 0 protostars in Orion.

Keywords: Infrared astronomy, Young stellar objects, Star formation, Variable stars
Inferences Regarding a Stellar Metallicity Distribution Following a Single Primordial Chemical Enrichment Event. An idealized scenario is presented according to which a power-law distribution in metallicity might have characterized the first metal-poor stars. The scenario assumes an initial synthesis of heavy elements within a first source of metals, followed by a subsequent ejection of these metals and their dilution within a metal-free gas environment.

Keywords: Stellar populations, Stellar abundances, Stellar nucleosynthesis
A Possible Extremely Fast Spinning White Dwarf in the Intermediate Polar SDSS J0932+47. We analyze the far-ultraviolet light curve of the intermediate polar (IP) candidate SDSS-J093249.57+472523.0 (J0932+47), as observed by Hubble Space Telescope/Cosmic Origins Spectrograph. The power spectrum displays two periodicities at frequencies of 2.01 and 0.462 cycles minute‑1, corresponding to periods of 29.8 and 130 s. We estimate the significance of the 29.8 s peak to be 3σ. The detection of the 130 s signal is less secure. If the 29.8 s signal is generated by a rotating white dwarf (WD), then J0932+47 would possess one of the fastest spinning WDs among known IPs. The N V/C IV and Si IV/C IV line ratios are larger than typically seen in cataclysmic variables (CVs), and anomalous line ratios are seen in several CVs with rapidly rotating WDs. Alternatively, the periodicities are in the range typical of dwarf nova oscillations.

Keywords: DQ Herculis stars, Cataclysmic variable stars, White dwarf stars, Dwarf novae
Negative Cosmic Evolution of BL Lac Objects from the Sloan Digital Sky Survey. BL Lacertae (BL Lac) objects are a type of active galactic nucleus (AGN) characterized by featureless optical spectra, where a relativistic jet is oriented toward the observer. By studying BL Lacs objects, we improve our understanding of accretion processes, high-energy particle acceleration, magnetic field structures in extreme environments, and galaxy formation and evolution. Generally, luminous AGNs (i.e., quasars) exhibit "positive" evolution. This means that, on average, quasars are more numerous and/or more luminous in the early Universe, at higher redshifts, than they are today. However, the evolution of BL Lacs has been long disputed, in part due to selection biases and small sample sizes. Here we perform the luminosity–volume test of BL Lac evolution on a uniformly selected sample and find that BL Lacs instead exhibit mild negative evolution. We conclude by putting our results into context with previous studies on BL Lac evolution.

Keywords: Blazars, Cosmological evolution, BL Lacertae objects
A Constrained Dust Opacity for Models of Dense Clouds and Protostellar Envelopes. Radiative transfer models of dense clouds and protostellar envelopes rely on the availability of appropriate dust opacities, particularly as new JWST data become available. We present the model opacity known as KP5, which fits the (1–1000 μm) extinction curve measured for icy dust in dense molecular clouds by Spitzer and JCMT, and has been used by the community since 2009, but not previously published. The opacity law (absorption, scattering, and Henyey–Greenstein asymmetry parameter) includes H2O, CO, and CO2 ices, and has been shown to be well suited for models of embedded protostars.

Keywords: Ice spectroscopy, Molecular clouds, Interstellar medium, Radiative transfer simulations, Circumstellar dust
The Expertise Finder: Using NASA ADS for Panel Reviewer Selection. Astronomical research is often made possible by the utilization of different resources that support members of the community in their research endeavors (e.g., telescopes access, or funds). Often, the entities that provide these resources establish a competitive process, which include the submission, by interested parties, of research proposals describing the research objectives and how the resources will be used to reach them. These proposals are evaluated by "ad hoc" panels of researchers, that provide a ranked list of the proposals based on their scientific relevance and other factors. This is also true for many NASA funding opportunities. In this article we present an open-sourced tool, the Expertise Finder, that simplifies the reviewers identification process. Expertise Finder provides NASA officials ways to scout prospective reviewers at small, less resourced, institutions that may have fewer opportunities to present and publish their research work with respect to colleagues at larger institutions.

Keywords: Astronomy software
Characterization of Instrumental Polarization in the MOPTOP Instrument. MOPTOP is a polarimeter currently installed on the fully robotic 2 m Liverpool Telescope, designed to allow accurate measurements of the variability of the polarization of astronomical objects like gamma-ray bursts and blazars. In this work, we present the characterization of the field position dependent instrumental polarization added by MOPTOP to the acquired images. This characterization is done by the acquisition of images of low polarized standard stars, for different positions over the CCD frame, for the filters BVRIL. These images were reduced using the MOPTOP pipeline, providing us with the q and u Stokes parameters. These values, in turn, were subtracted from the q and u values of the respective star, found in literature, resulting in the spatial distribution of the residual polarization added by the instrument. A plane was fitted to the obtained result, allowing us to calculate the q and u values added by MOPTOP.

Keywords: Polarimeters, Starlight polarization, Polarimetry
The Abundances of the Noble Gases Neon and Xenon in the Atmosphere of 53 Tau (HD 27295). One line of Ne I and three lines of Xe II are synthesized in order to derive the abundances of neon and xenon in the atmosphere of the Mn-rich star 53 Tau. Neon is clearly very underabundant in 53 Tau, its abundance must be lower than 10‑3 times the solar neon abundance. Xenon is found to be overabundant with a factor of 3000 times the solar abundance which agrees well with earlier measurements. The underabundance of neon is expected from radiative acceleration calculations which show that neon has a very small radiative acceleration in the photosphere.

Keywords: Chemically peculiar stars, Manganese stars
Massive OB Star Clusters in Cassiopeia. We present a new investigation of several sparse OB associations in Cassiopeia (Cas OB2, OB4, OB5, OB7, and OB8) to revisit their membership and kinematics in the Gaia era. We compare the spatial distribution of the OB associations' members, the known OB-type stars from the Reed catalog, and candidate hot stars from the Gaia Data Release 3. We also investigate the reddening distributions across the region to further understand the kinematics of these groups relative to the region's molecular clouds.

Keywords: Young massive clusters, OB associations
Multiwavelength Catalog of 10,000 4XMM-DR13 Sources with Known Classifications. We present a collection of ∼10,000 X-ray sources from the 4th XMM-Newton Serendipitous Source Catalog (4XMM-DR13) with literature-verified classifications and multi-wavelength (MW) counterparts. We describe the process by which MW properties are obtained and an interactive online visualization tool we developed.

Keywords: X-ray astronomy, Neutron stars, Surveys, Catalogs, High mass x-ray binary stars, Young stellar objects, X-ray active galactic nuclei, Low-mass x-ray binary stars, Cataclysmic variable stars, X-ray stars
A Spectroscopic Hunt for Post-red Supergiants in the Large Magellanic Cloud. I. Preliminary Results. Yellow supergiants (YSGs) are rare and poorly understood, and studying them is critical to constraining massive star evolution. We obtained flux-calibrated Magellan Inamori Kyocera Echelle high-resolution spectra of 40 YSGs in the Large Magellanic Cloud (LMC); this sample likely contains post-red supergiants. Fitting these data with ATLAS9 model atmospheres, we determined fundamental parameters for these stars. We measure the first spectroscopic luminosities for YSGs above 20 M ☉, providing us a novel probe of the luminosity-to-mass ratio. Many stars in our sample appear to have anomalously high surface gravities, despite being confirmed LMC supergiants. We manually inspected our data finding evidence for binary companions and ongoing mass loss. Our work demonstrates the valuable role of high-resolution spectroscopy in interpreting the evolutionary status of cool supergiants.

Keywords: High resolution spectroscopy, Binary stars, Core-collapse supernovae, Stellar pulsations, Massive stars, H-alpha stars, Stellar classification, Late-type supergiant stars, Stellar evolution
Neglect of Small Spots Remains an Explanation of the Difference Between SOON and RGO Spot Areas. I point out that the objection of Györi et al. to my finding that neglect of small spots could explain much of the puzzling difference between Royal Greenwich Observatory and Solar Optical Observation Network spot areas is not valid because their analysis was limited to only 1974–76, when activity was low. The 40%–50% difference occurs only at higher activity levels.

Keywords: Delta sunspots
A Catalog of Compact Blue Strongly Lensed Sources in the Footprint of Ground-based Surveys. We present a catalog of Compact Blue Strongly Lensed Sources in the footprint of ground-based surveys. We visually inspected the high-quality strong lensing candidates from the Kilo Degree Survey, the Hyper Suprime-Cam Subaru Strategic Program and the Dark Energy Survey. We have collected 63 multiple-imaged systems that are similar to the lensed post-blue nuggets found in Napolitano et al. and fully characterized in Li et al. Data, including gri cutouts, are made publicly available (https://cosviewer.com/en/special-objects#bluenuggets).

Keywords: Gravitational lensing, Catalogs
Lightcurve Analysis of a Sample of Asteroids and Comets Observed with the Isaac Newton Telescope. We present an analysis of six asteroids and one comet using data from the Wide Field Camera on the Isaac Newton Telescope, La Palma. As part of this work we developed a pipeline to reduce and absolutely calibrate photometry of inactive small bodies. For three of the objects, there was sufficient data to measure their rotation periods. We report rotation periods of (2.7774 ± 0.0004) hr and (3.121 ± 0.003) hr for main belt asteroids (7891) Fuchie and 1999 CP29 respectively, neither of which to our knowledge currently have a well-constrained rotation period. We also measure a rotation period for Jupiter-family comet 169P/NEAT of (8.37 ± 0.04) hr which is consistent with previous works. Colours in various filter combinations (Sloan $r^{\prime} $ , $g^{\prime} $ , $i^{\prime} $ and RGO Z) were also determined, and for the six observed asteroids we present an approximate taxonomic classification.

Keywords: Light curve classification , Asteroids, Light curves, Main belt asteroids, Planetesimals