Sazuna/UAT_keywords huggingface dataset:
A Convolutional Neural Network–Based Approach for Detecting Solar System Objects in Wide-field Imaging. We present a deep learning method that utilizes convolutional neural networks (CNNs) to discover trans-Neptunian objects (TNOs) in wide-field survey imaging data. Our CNNs were trained using artificial sources planted into a time series of 44 205 s CFHT MegaCam large-format mosaic images. We extracted 64 × 64 pixel subimages and labeled each subimage pair with the presence or absence of a moving source and the source's location and magnitude. Our MobileNet-derived classification model achieved 91% recall with 90% precision on test data. A separate regression model predicted the source locations with a mean absolute error of ±1.5 pixels for sources with a signal-to-noise ratio (SNR) of 16.5 or higher. By grouping sources based on linear sky motion, we achieved ∼40% detection limit for sources with an SNR ≈ 7 in individual frames. We also examined a scoring approach to reduce the false positives. In this approach, images are scored based on the probability values from the classification model. With the scoring approach, we achieved a detection limit of SNR ≈ 3 in individual frames. We detected approximately 200 solar system object (SSO) candidates (sim5 moving rates consistent with TNOs) in our 1 square degree of imaging. We tested the trained models on images from different sky regions, confirming that the models learned from the motion of sources rather than from the backgrounds or shapes of sources. We demonstrate that deep learning object detection algorithms can aid in TNO and SSO discovery, supporting future discovery pipeline development.

Keywords: Detection, Solar system, Kuiper belt, Neural networks
A Limit on the Mass of the Taurid Resonant Swarm at Sub-100 m Sizes. We report on a pencil-beam survey of the Taurid resonant swarm (TS), a possible concentration of bodies in the Taurid meteoroid stream associated with the 7:2 mean motion resonance with Jupiter. Canada─France─Hawaii Telescope MegaCam observations reaching apparent magnitudes of 24.5 in the gri filter were taken over 3 nights. Rates of motion on the sky allowed for the quick elimination of main-belt objects from the over 1000 moving sources seen. Eight candidates with on-sky rates of motion consistent with Taurids were detected, but seven were subsequently shown to be non-Taurids (Hungarias, Mars crossers, etc.). One object might be a 60 m class Taurid, but not enough data were collected and its orbit remains ambiguous. Our results are consistent with no Taurid swarm members observed, and an upper limit of fewer than 3 × 103─3 × 104 objects down to H = 25.6 ± 0.3 (diameter of  47−13+29  m assuming a 2P/Encke-like albedo) at the 95% confidence level. While meteor observations have confirmed the TS's existence at meter and smaller sizes, our results indicate that the current mass budget of the swarm at 100 m sizes does not require an outsize parent to explain it.

Keywords: Near-Earth objects, Comets, Asteroids, Small Solar System bodies
Atmospheric Loss during Giant Impacts: Mechanisms and Scaling of Near- and Far-field Loss. The primary epoch of planetary accretion concludes with giant impacts—highly energetic collisions between protoplanets that can play a key role in shaping a planet's inventory of volatile elements. Previous work has shown that single giant impacts have the potential to eject a significant amount of a planet's atmosphere but that the efficiency of atmospheric loss depends strongly on the impact parameters and atmospheric properties. Fully quantifying the role of giant impacts in planetary volatile evolution requires a more complete understanding of the mechanisms driving loss during impacts. Here, we use a suite of 3D smoothed particle hydrodynamics simulations to show that loss in giant impacts is controlled primarily by ejecta plumes near the impact site and breakout of the impact shock in the far field, with the efficiency of the latter well approximated by 1D ground-kick calculations. The relative contribution of each mechanism to loss changes drastically with varying impact parameters. By considering the near and far fields separately, we present a scaling law that precisely approximates (to within an average of ∼3%) loss from 0.35 to 5.0 M⊕ planets with 5% mass fraction H2–He atmospheres for any combination of impactor mass, impact velocity, and angle. Finally, we apply our scaling law to the results of N-body simulations for different solar system formation scenarios. We find that while individual impacts rarely cause significant loss (&gt;10%) from roughly Earth-mass planets with such massive primary atmospheres, the cumulative effect of multiple impacts can be substantial (40%–70% loss).

Keywords: Impact phenomena, Hydrodynamics, Atmospheric evolution, Planet formation
Surface Ages for the Sample Return Asteroids Bennu, Ryugu, and Itokawa. The OSIRIS-REx, Hayabusa2, and Hayabusa missions have returned samples from three near-Earth asteroids (NEAs), namely Bennu, Ryugu, and Itokawa, respectively. Insights into the geological and dynamical history of these NEAs can be gleaned by linking their surface ages, derived by modeling the production of their crater size–frequency distributions, to the cosmic-ray exposure (CRE) ages of their samples. The complication is that as these NEAs traveled from the main belt to their observed orbits, the impactor flux striking them from main-belt asteroids, Mars-crossing asteroids, and NEAs also changed. Here we account for these factors by allowing Bennu, Ryugu, and Itokawa to dynamically evolve within a crater production model. Each world was tracked over many tens of different orbital pathways. Crater erasure effects, produced by superposed craters, sandblasting effects, and the impact-driven mass movement of surface materials, were also included, with the latter parameterized using a crater damage function. Surface ages were determined by comparing model crater size–frequency distributions to the observed ones. Our results yielded median surface age values for Bennu, Ryugu, and Itokawa of 7.7, 4.1, and 3.2 Myr old, respectively. These model ages are broadly consistent with the CRE ages measured from the returned samples. We suggest that these model ages may represent the timing of global resurfacing events, with the most likely mechanisms being shattering impacts from main-belt projectiles and YORP-driven spin up. When combined with cratering events, we predict that near-surface materials on Bennu, Ryugu, and Itokawa have experienced considerable churn with time.

Keywords: Impact phenomena, Near-Earth objects, Asteroid dynamics, Meteorites, Asteroid belt, Craters
The Composition and Stratigraphy of the Chang'e-6 Landing Mare. China's Chang'e-6 (CE-6) mission returned lunar samples from the southern mare in the Apollo basin formed in the prominent South Pole–Aitken basin. The basic geological context of the landing mare has been well resolved. Separated by a north–south extending high-standing wrinkle ridge, the western and eastern parts of the southern mare have different compositions and model ages of emplacement. However, the stratigraphic context of the landing mare, especially the eruption sequence of the basaltic deposits, is marginally constrained due to the prolonged regional geological history and prominent mixing by exotic ejecta. This shortage of knowledge could be a challenge in sample investigations. In this work, we investigated the reflectance spectra for fresh materials of young craters to analyze the composition and stratigraphy of the landing mare. We verified that the western mare where CE-6 landed is composed of at least two layers of basaltic deposits. The surface basaltic deposits have a higher content of TiO2 (∼3.7 wt%) than the underlying lower basaltic deposits (∼2.3 wt% TiO2), which share similar compositions with the eastern mare. Potential flow fronts of basaltic flows that originated from the west are observed on top of the wrinkle ridge, and they have similar compositions to the eastern mare. These new lines of evidence support that the basaltic deposits in the eastern mare existed beneath the western mare, suggesting that the eruption was located within the western mare. The regional stratigraphic context is helpful for ongoing sample analyses.

Keywords: Lunar impacts, Lunar surface, Lunar mineralogy, Lunar regolith
A Pan-STARRS Search for Distant Planets: Part 1. We present a search for distant planets in Pan-STARRS1. We calibrated our search by injecting an isotropic control population of synthetic detections into Pan-STARRS1 source catalogs, providing a high-fidelity alternative to injecting synthetic sources at the image level. We found that our method is sensitive to a wide range of distances, as well as all rates and directions of motion. We identified 692 solar system objects (109 of which are not yet listed in the Minor Planet Center's database), including 642 trans-Neptunian objects, 23 of which are dwarf planets. By raw number of detections, this makes our search the third most productive Kuiper Belt survey to date, in spite of the fact that we did not explicitly search for objects closer than 80 au. Although we did not find Planet Nine or any other planetary objects, we were able to show that the remaining parameter space for Planet Nine is highly concentrated in the Galactic plane.

Keywords: Dwarf planets, Solar system, Kuiper belt, Solar system planets
Unoccupied Aircraft Systems Sampling for Earth and Mars. Unoccupied aircraft systems (UAS) technology on Earth has become increasingly prevalent and accessible, and for extraterrestrial applications, the Ingenuity helicopter has proven the viability of flight on Mars. Advantages provided by UAS on both Earth and Mars include faster and broader access to traditionally difficult-to-reach terrain. Here, we demonstrate the use of UAS-based sample collection and retrieval systems for applications on Earth and Mars, which we tested in Martian analog sites in the Holuhraun region of Iceland, at the Galena Creek rock glacier in Wyoming, and around the Eastern Sierra in California. The two sampling systems include a Drill Sampler and a Scoop Sampler, both coupled to commercial off-the-shelf drones. The Drill Sampler is a lightweight rotary-percussive coring drill with powder collection capability, compliantly mounted to the UAS to allow for drilling into a variety of different materials and uneven terrain. The Scoop Sampler uses modular interchangeable scoops for collecting and retrieving different types of samples. These sampling systems collected a suite of various samples, including rock cores, bulk samples, and replica Mars sample tubes. By collecting various samples in diverse terrains, we show that this technology enables adaptable sampling and sample transport for both earthbound and future planetary exploration missions.

Keywords: Planetary surfaces, Planetary geology
From Colors to Spectra and Back Again: First Near-IR Spectroscopic Survey of Neptunian Trojans. In this work, we present 0.7–5.0 μm spectra of eight Neptunian Trojans (NTs) as observed by the JWST's NIRSpec instrument. The reddest NT, 2013 VX30, exhibits a unique spectrum with strong absorption features between 3 and 4 μm, while the bluest NT, 2006 RJ103, shows negligible water absorption. A principal component analysis comparing these spectra with those of trans-Neptunian objects (TNOs) and Centaurs reveals that most NTs belong to the "bowl-type" spectral group, while 2013 VX30 is categorized as "cliff-type" in the N. Pinilla-Alonso et al. taxonomy. For the bluest NT in our sample, 2006 RJ103 shows some evidence that it may be related to carbonaceous asteroids. For the red object 2011 SO277, we find no close TNO spectral counterpart. Except for the true outlier 2011 SO277, NTs have better spectral analogs among Plutinos and distant Centaurs, suggesting that spectral variation within major groups may arise from current temperature and location, rather than solely from formation regions. Finally, we highlight optical slope (S') and near-IR slope (SIR1) as effective indicators for distinguishing spectral groups and identifying outliers. These findings enable the use of broadband photometry to explore NT and TNO surface compositions, especially for faint objects, which will be directly applicable to large photometric surveys like the Dark Energy Survey and the Vera C. Rubin Observatory's LSST.

Keywords: Multi-color photometry, Infrared spectroscopy, Neptune trojans
High-speed Boulders and the Debris Field in DART Ejecta. On 2022 September 26 the Double Asteroid Redirection Test (DART) spacecraft collided with Dimorphos, the moon of the near-Earth asteroid 65803 Didymos, in a full-scale demonstration of a kinetic impactor concept. The companion Light Italian Cubesat for Imaging of Asteroids (LICIACube) spacecraft documented the aftermath, capturing images of the expansion and evolution of the ejecta from 29 to 243 s after the impact. We present results from our analyses of these observations, including an improved reduction of the data and new absolute calibration, an updated LICIACube trajectory, and a detailed description of the events and phenomena that were recorded throughout the flyby. One notable aspect of the ejecta was the existence of clusters of boulders, up to 3.6 m in radius, that were ejected at speeds of up to 52 m s‑1. Our analysis of the spatial distribution of 104 of these boulders suggests that they are likely the remnants of larger boulders shattered by the DART spacecraft in the first stages of the impact. The amount of momentum contained in these boulders is more than 3 times that of the DART spacecraft, and it is directed primarily to the south, almost perpendicular to the DART trajectory. Recoil of Dimorphos from the ejection of these boulders has the potential to change its orbital plane by up to a degree and to impart a non-principal-axis component to its rotation state. Damping timescales for these phenomena are such that the Hera spacecraft, arriving at the system in 2026, should be able to measure these effects.

Keywords: Impact phenomena, Near-Earth objects, Asteroids, Asteroid dynamics, Calibration, Asteroid satellites
LiDO: Discovery of a 10:1 Resonator with a Novel Libration State. The Large inclination Distant Objects (LiDO) survey has discovered the first securely classified object in the 10:1 mean motion resonance of Neptune. This object, 2020 VN40, is short-term stable in the 10:1 resonance, but not stable on Gyr timescales. 2020 VN40 is likely part of the scattering sticking population, and temporarily resides in the 10:1 resonance at ∼139.5 au. This discovery confirms that this distant resonance is populated, as a single detection is likely to be indicative of a large population that is difficult to detect due to observational biases. This object has an inclination of 33 .° 4, and n-body integrations of orbital clones of 2020 VN40 have revealed some unexpected evolutions. While clones of 2020 VN40 show resonant libration around the expected resonance centers of approximately 90°, 180°, and 270°, for a restricted range of inclination and eccentricity values some clones librate around a resonant argument of 0°. As this occurs for the slightly lower-eccentricity portions of the evolution, this behavior can also be quite stable. Our initial exploration suggests that this libration around a center of 0° is a generic effect for highly inclined objects in n:1 resonances because the nature of their resonant interaction with Neptune becomes a strong function of their argument of pericenter, ω. At large inclination, the resonant islands shift as ω precesses, switching the center of symmetric libration to 0° for ω = 90° and ω = 270°. 2020 VN40 provides interesting insight into the evolution of the large-inclination resonators, which become more common at increasing semimajor axes.

Keywords: Resonant Kuiper belt objects, Trans-Neptunian objects
DART-scale Impacts into a Complex Low-strength Target: Insights into Asteroid Dimorphos's Interior from Simulations. Impact processes are fundamental in governing asteroid evolution. While recent space missions have provided ground-truth observations of the surface and orbital dynamics, interior features remain largely unexplored. NASA's Double Asteroid Redirection Test (DART) mission recently achieved a successful kinetic impact on the near-Earth asteroid Dimorphos. The spacecraft imagery detected a boulder-strewn surface in the seconds before the impact, though its underlying structure remains uncertain. To examine the subsurface of Dimorphos, we modeled DART-scale impacts as a window into its interior. Impacts were simulated using the iSALE-2D shock physics code over extended time frames of up to 60 s, with half-spheroidal targets resolving surface curvature effects. Recent mechanical and material settings were incorporated based on the DART constraints. Among the scenarios tested, homogeneous cases with low cohesions (20–80 Pa) were found to match the reference β range reconstructed for the DART impact when the coefficient of internal friction was 0.5, if Dimorphos has the same bulk density as the binary system. This cohesion range represents one possible solution; alternatively, a lower cohesion (1 Pa) reproduced the reference β when the porosity was reduced to 20%. For heterogeneous scenarios, a double-layered interior featuring a loose layer surrounding a weak core, and a three-layered interior with multiple boulders clustered at the impact site produced β aligning with the reference β, implying the plausibility of diverse interiors for Dimorphos. The results provide insights into the interior morphology of Dimorphos, set to be probed by the European Space Agency Hera mission, with a rendezvous in late 2026.

Keywords: Impact phenomena, Near-Earth objects, Small Solar System bodies, Asteroids, Asteroid satellites
Lunar Crustal Magnetization Sourced via the Delivery of Iron-rich Ejecta from Basin-forming Impacts. The reason for the prevalence of crustal magnetic anomalies within a lunar crust composed of materials that do not retain strong magnetization remains an unresolved question in lunar science. Delivery of iron-rich material from basin-forming projectiles could potentially explain the origin of regions of lunar crust rich in magnetic carriers and the distribution of such regions antipodal to large lunar impact basins. However, the likelihood of projectile material being deposited antipodal to the impact site during basin-forming impacts remains unexplored for a wide range of impact parameters. In this work, we examined the post-impact distribution of iron-rich projectile ejecta from a wide range of lunar basin-forming impacts. We found antipodal ejecta deposits were sufficiently thick to explain magnetic anomalies for impacts with v = 12 km s‑1 or 16 km s‑1, θ = 30° or 45°, and D = 100–250 km, although such impacts also produced significant near-basin ejecta deposits.

Keywords: Collisional processes, Lunar magnetic fields, Lunar science, Lunar impacts, Lunar surface, Planetary science, Lunar evolution
Rotationally Resolved Near-infrared Spectroscopy of Three Large Eurybates Family Members. The Eurybates family is the largest collisional family in the Jupiter Trojan population. Previous visible spectroscopy of asteroid (3548) Eurybates has shown potential surface heterogeneity due to rotation of the asteroid. New near-infrared (NIR; 0.7–2.52 μm) spectra of the three largest family members, (3548) Eurybates, (8060) Anius, and (18060) Zarex, were obtained with the NASA Infrared Telescope Facility. At least two spectra of each object were obtained, at different points of their respective rotational periods, to assess if they were compositionally heterogeneous as suggested by visible spectroscopy of (3548) Eurybates. The spectral slope,  S' , between 0.95 and 2.30 μm was computed for each spectrum, and the  S'  for each observation was compared to the average spectrum of each object to look for significant deviation from the mean. No evidence of rotational heterogeneity was found in the NIR on any of the three objects. Additionally, (8060) Anius is classified as a C type based on visible and NIR spectroscopy. The lack of rotational variability in the NIR suggests that the Eurybates family formed from the breakup of an undifferentiated asteroid. Future observations by the NASA Lucy mission will provide high-resolution and rotationally resolved spectra of (3548) Eurybates, allowing for a ground-truth assessment of heterogeneity on the surface.

Keywords: Jupiter trojans, Infrared spectroscopy, Asteroid surfaces
An Estimate of the Importance of Electron-stimulated Desorption of Sodium at Mercury. We revisit the importance of electron-stimulated Desorption (ESD) as a source of neutral sodium (Na) atoms and Na+ ions in Mercury's exosphere and ionosphere. For the first time we have calibrated the ESD yield per electron as a function of electron energy in the energy range 100–950 eV. This calibrated yield per electron was convolved with the electron flux as a function of energy onto Mercury's cusps to determine the average release rate of Na+ to the exosphere, using electron flux and cusp area estimates from a recent hybrid magnetosphere model. Given that previous work showed the ESD yields per electron of Na+ ions and neutral Na atoms are approximately equal, we compared the energy-weighted ESD release of Na+ to that deriving from micrometeoroid impact vaporization, photon-stimulated desorption, and ion sputtering. We conclude that ESD is not a significant source of neutral Na atoms or Na+ ions to Mercury's exosphere.

Keywords: Mercury (planet), Exosphere
Spectroscopic Mapping of Callisto with HST/STIS and Implications for its Surface Composition. We present global, spatially resolved ultraviolet─visible spectra of Callisto obtained with the Hubble Space Telescope/Space Telescope Imaging Spectrograph and explore possible compositions of Callisto's surface material. We map the strength of a widespread downturn toward the near-UV and the near-infrared (NIR) spectral slope from 700 to 1000 nm, which varies from slightly blue (reflectance decreasing from 700 to 1000 nm) to red (reflectance increasing) across Callisto's surface. Globally, bright water-ice-rich regions tend to have neutral or blue NIR slopes and a shallower near-UV downturn, while darker material is associated with red NIR slopes and stronger near-UV absorption. Broad absorptions near 820 and 930 nm are spatially correlated with the Asgard and Valhalla impact basins and may be associated with iron-bearing silicates. An absorption edge near 275 nm maps primarily to Callisto's trailing hemisphere, and a 320 nm absorption most prevalent within and surrounding Asgard and Valhalla may be related to organics. We report two new absorption features near 230 and 450 nm, which might be attributed to irradiated NaCl. We find little evidence for sulfur-bearing species at UV─visible wavelengths and suggest that a 280 nm band seen only in leading/trailing hemisphere ratio spectra and previously attributed to SO2 is better explained as a consequence of dividing the unrelated 320 nm leading hemisphere band by the trailing hemisphere 275 nm absorption edge. Spatial variations in spectral features suggest that Callisto's dark material composition varies regionally, reflecting a mix of endogenic and exogenic sources and radiolytic alteration.

Keywords: Callisto, Natural satellite surfaces, Surface composition, Ultraviolet spectroscopy, Galilean satellites