adsabs/AstroCLIMB huggingface dataset:
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: The three PAM operators (flyers) on the Zero-G Corp. parabolic flight campaign in 2019 free-floating the frame assemblies during one of the reduced-gravity maneuvers.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: (a) An example frame from a raw video clip from a free float, (b) cropped and separated into the blue color channel, (c) processed into a threshold image, and (d) distinct aggregates identified by ImageJ software for particle tracking.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: PAM experiment free-float assembly with foam-core wings shown in various orientations and lighting as assembled prior to flight.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: PAM experiment hardware parts groups/subassemblies. The clear experiment box assembly is seen at lower right and is placed in flight within the experiment box frame seen at lower left. Two camera brackets (Top) attach to the box frame. (Bottom) The double boxed chamber and pressure relief hole.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: Measured aggregate size ratios of the five materials we tested for the 3 g sample mass (0.0021 g cm−3) for the 125–250 μm PSD.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: Measured aggregate size ratios of the five materials we tested for the 3 g sample mass (0.0021 g cm−3) at the <63 μm PSD. The UCF-CI-2 data here were flown on the Canadian NRC Falcon-20 aircraft.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: Flyers (left to right) Whizin, Tsang, and Durda executing the steps (a)–(d) of the experiment procedure during the four stages of the Zero-G parabolic maneuvers inside Zero-G’s research aircraft (e).
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: PAM payload secured in a Pelican case that is bolted to the aircraft floor during flight. The lid is opened and boxes exchanged during the flight. We brought eight boxes of different materials on board each of the four parabolic flight campaigns.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: Sieved and size-sorted material samples inside the box assemblies prepped before flight.
Paper: Detection of New Auroral Emissions at Io and Implications for Its Interaction with the Plasma Torus
Authors: Zachariah Milby, Katherine de Kleer, Carl Schmidt
Figure caption: Calibrated example images for all 19 detected auroral emissions listed in Table 2, displayed using 20 discrete contours. Each image is a single, 5 minute integration with the background subtracted. To better reveal the emissions, we smoothed the data using a two-dimensional Gaussian kernel with an FWHM of 0﹩\mathop{.}\limits^{\unicode{x02033}}﹩5 approximating typical seeing conditions for Maunakea. Due to the large range of brightnesses, we scaled each image using its individual dynamic range, so comparing apparent brightnesses between images is not meaningful. Graticules in the lower left corner of each panel show the size and orientation of Io during the observation; the thicker dashed line shows the location of the prime meridian. (We chose not to display these directly over the emission in order to not interfere with interpretation of the dimmer emissions and to prevent the need to display three overlapping globes for the 844.6 nm O I triplet.) For the 777.4 nm O I and 922.3 nm S I triplets we have displayed only the brightest, shortest-wavelength component owing to the large separation of the three emissions on the HIRES detector. However, we used all three components simultaneously when retrieving the total brightnesses. The three components of the 844.6 nm O I triplet are somewhat blended at the HIRES detector resolution, so we centered that image on its average wavelength. The 732.0 and 733.0 [O II] emissions are both doublets, and we chose the brighter components at 731.999 and 732.967 nm, respectively.(The data used to create this figure are available in the online article.)(The data used to create this figure are available.)
Paper: Detection of New Auroral Emissions at Io and Implications for Its Interaction with the Plasma Torus
Authors: Zachariah Milby, Katherine de Kleer, Carl Schmidt
Figure caption: Morphological features of Io’s optical emission in eclipse. This image was taken by the NAC on Cassini’s ISS with the CL1+CL2 (clear) filter combination, so it includes emission across the full detector sensitivity range from approximately 235 to 1100 nm. The volcanic features Pele and Reiden Patera also include thermal emission, especially at longer wavelengths. Table 5 lists the file name and observation time for this image.(The data used to create this figure are available in the online article.)(The data used to create this figure are available.)
Paper: Detection of New Auroral Emissions at Io and Implications for Its Interaction with the Plasma Torus
Authors: Zachariah Milby, Katherine de Kleer, Carl Schmidt
Figure caption: Cassini/ISS NAC filter transmission (C. C. Porco et al. 2004) and locations of identified auroral emission features. Panel (a) shows all the wideband filters and the locations of all auroral lines, grouped as necessary to avoid overlap of the labels. Panel (b) shows the narrowband filter CB1 and the filters made by the combination of two broadband filters, along with the emission features that correspond to those filter bandpasses.(The data used to create this figure are available in the online article.)(The data used to create this figure are available.)
Paper: Detection of New Auroral Emissions at Io and Implications for Its Interaction with the Plasma Torus
Authors: Zachariah Milby, Katherine de Kleer, Carl Schmidt
Figure caption: Example viewing geometry of the apparent motion of Io in eclipse relative to Jupiter for egress observations on 2022 November 24 (left) and ingress observations on 2023 August 25 (right). Each drawing of Io shows its position relative to Jupiter for each of the spectra taken on these nights, and the annotated times show the UTC time at the start of the first and last observations. The last observation also includes the angular projection of the slit on the sky and its orientation (the slit size and orientation were fixed for all observations on a given night).
Paper: Modeling Ice and Dust in Comet C/2017 K2 (Pan-STARRS)’s Coma
Authors: Megan Firgard, Theodore Kareta
Figure caption: Two corner plots showing the MCMC distributions for two different models of K2’s spectra from the 2022 September 5 Gemini South data. These models are linear mixing with Mie scattered crystalline water ice at 100 K and Hapke scattering, F. Rouleau & P. G. Martin (1991) amorphous carbon (left), and linear mixing with Mie scattered amorphous water ice at low temperatures and Hapke scattering, F. Rouleau & P. G. Martin (1991) amorphous carbon (right).
Paper: Leveraging Ceres to Gain Insights into the Candidate Ocean Worlds of Umbriel and Oberon That Orbit Uranus
Authors: Jennifer E. C. Scully, C. Adeene Denton, Julie C. Castillo-Rogez, Michael M. Sori, Erin J. Leonard, Chloe Beddingfield, Richard Cartwright, Catherine M. Elder, Karl L. Mitchell, Tom A. Nordheim
Figure caption: Morphologically analogous features on Umbriel, Oberon, and Ceres. (a) Bright deposit in Wunda crater, Umbriel, viewed from the side, with inset box highlighting Wunda crater. Image number 2684004, ∼4 km pixel−1. (b) Faculae in Occator crater, Ceres, also viewed from the side, with inset box highlighting Occator crater. Image number 37114, originally ∼1.3 km pixel−1 but reduced by 3× to be ∼4 km pixel−1. (c) The unnamed mountain on Oberon, viewed from the side, with inset box highlighting the mountain. Image number 2683623, ∼5 km pixel−1. (d) Ahuna Mons on Ceres, viewed from the side, with inset box highlighting Ahuna Mons. Image number 36633, originally ∼1.3 km pixel−1 but reduced by 4× to be ∼5 km pixel−1.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: The left panel illustrates the orientation parameters (φ, θ) used to define the orientation of the multibody system at perigee. The middle panel defines two types of mass shifts: the large component shift, represented by the secondary’s offset in the primary’s body-fixed frame, and the surface mass shift, shown as the displacement of surface boulders. The right panel shows the trajectory of Apophis during the 12 hr flyby simulation, projected onto the y–z plane, with the perigee aligned along the y-axis to better define the relative orientation.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: The left panel compares the 30 days and 12 hr flyby simulations by total angular momentum, demonstrating that the most significant interactions occur within the 12 hr window. The bottom plot within the left panel shows negligible changes in spin state during the short-term simulation. Differences in behavior are attributed to the asteroid’s rotation and orientation at perigee, introducing potential uncertainties in determining its precise orientation. The right panel illustrates the trajectory of Apophis during the 12 hr flyby simulation, projected onto the x–y plane.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: Large component shift for the DSC-NB model at different friction angles and orientation angles φ while θ = 0 (left) and θ while φ = 0 (right). Significant large component shifts are observed at specific orientations. Like the DSC model, the largest shifts occur slightly offset from the orientation where Apophis’ longest axis points directly toward Earth at perigee. Friction amplifies large component shifts by causing the boulders in the neck region to compress and resist motion in the DSC-NB model.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: Comparison of two simulation cases using the DPM-NB model: one with no initial spin (dashed line), and one with a uniform initial spin along the z-axis (solid line), each tested under different orientations. Due to the inherent uncertainty in the rotational case, the orientation at perigee deviates from the nominal values shown in the figure. This figure illustrates that both cases exhibit similar ranges of spin rate variation, indicating that the static model effectively captures the full spectrum of possible changes in spin rate.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: The figure shows the large component shift across different tensile strength values for the DPC, DPC-NB, DPC-FB, DSC, DSC-NB, and DSC-FB models. The DSC and DPC models establish the upper and lower bounds, respectively, while the large component shift remains relatively insensitive to tensile strength variations. The orientation angles are set to φ = 60° and θ = −60°.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: Large component shift for the DPC-NB model at different friction angles and orientation angles φ while θ = 0° (left) and θ while φ = 0° (right). The large component shift (ranging from 0﹩\mathop{.}\limits^{\unicode{x000b0}}﹩01 to 0﹩\mathop{.}\limits^{\unicode{x000b0}}﹩1) is relatively insensitive to variations in friction and orientation, with the random shape of the polyhedral regolith boulders being the primary source of uncertainty.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: The left panel compares the large component shifts of the eight models at different orientation angles φ while θ = 0°. The right panel compares the large component shifts of the eight models at different orientation angles θ while φ = 0°.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: Surface mass shift for the DSC-NB and DPC-NB models at different orientation angles φ while θ = 0° (left) and θ while φ = 0° (right). The DSC-NB model shows a significantly larger surface mass shift than the DPC-NB model, with the surface mass shift remaining largely insensitive to changes in friction and orientation, on the centimeter scale.
Paper: Simulating the (99942) Apophis Earth Flyby Using a Contact Binary Model
Authors: Hai-Shuo Wang, Paul Sánchez, D.J. Scheeres
Figure caption: The figure displays the DPC-NB model configurations with varying neck and boulder size ratios.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: Dependence of the H2O2 creation cross section (σc), G-value, H2O2 destruction cross section (σd), and steady-state H2O2 abundance on the initial CO2 abundance in water ice irradiated at 70 and 100 K. Both σc and G-value increase linearly with CO2 amount, with steeper slopes at 100 K (panels (a) and (b)). This rise suggests that CO2 promotes peroxide synthesis primarily via multiple H-atom abstraction by CO, synthesizing CHO organics and resulting in an excess of OH radicals. More striking is the sharp decline in σd with CO2 inclusion (panel (c)), which has a steeper plunge at 100 K (∼5×) than at 70 K (∼2.5×). This sharp decrease in σd is likely due to CO2-mediated shielding mechanisms that protect H2O2 from destruction by either secondary electrons or OH radicals. The scavenging of electrons and/or OH radicals by CO2 or its radiolytic products is expected to be more efficient at higher temperatures, hence the steeper decline at 100 K. A small rise in σd at larger CO2 levels reflects H2O2 destruction facilitated by CO2. Panel (d) shows the steady-state H2O2 abundance, (σc/σd) × ηw, plotted against CO2 amount. The sharp rise in H2O2 yield mirrors the decline in σd below 3% CO2. See text for further discussion on mechanisms underlying these results.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: Fluence-dependent synthesis of H2O2 in 2.8 μ m-thick pure and CO2-containing water-ice films irradiated with 10 keV electrons at 70 and 100 K. (a) In pure water ice, H2O2 yields are higher at 100 K at low fluences, but this trend reverses above 3 × 1014 e− cm−2, with the 70 K ice presenting nearly 4× higher steady-state peroxide abundance. Solid curves are model fits to the data discussed in the text. (b, c) Trace inclusions of CO2 markedly increase H2O2 yields, with greater enhancements at warmer temperatures. At 70 K H2O ice with 2.5% CO2 shows a ∼2.5-fold increase (indicated by the arrows), while at 100 K ice with 3.1% CO2 yields a notable sixfold enhancement over pure ice. Minor organics contributions to the 3.5 μm absorption have been removed. Mechanisms underlying this CO2-induced boost in H2O2 are discussed in the text.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: (a) Normalized band area of the CO2 4.27 μm absorption band vs. fluence during 10 keV electron irradiation of H2O ice with varying initial CO2 concentration. The films were irradiated at 70 K until H2O2 saturation was reached, at which point ∼25% of the CO2 was consumed. Inset: desorption rate (in equivalent H2CO3 ML s−1) vs. temperature of radiolytic C-bearing residue formed after irradiating water-ice film containing 7.4% CO2 at 70 K (black curve). Most (>60%) of the consumed CO2 contributes to the formation of H2CO3, which desorbs near 255 K. The blue curve in the inset represents a film with 6.2% CO2 irradiated at 100 K, showing that organic production is enhanced by 14% compared to the colder 7.4% CO2 film. (b) Comparison of the continuum-subtracted IR spectra of the organics residue at the indicated temperatures for the film with 7.4% CO2. This thin film fully desorbs above 260 K. The spectra have been offset vertically for clarity.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: (a) Schematic of the ultrahigh vacuum chamber used for electron irradiation experiments of Europan ice analogs. (b) Shift in the resonant frequency of the QCM during co-deposition of H2O and CO2 ice from dedicated gas dosers. We first condense CO2 [1] from a doser at a constant rate of 0.25 ± 0.01 Hz s−1 (zoomed in the inset). We then admit water vapor [2] through a second doser, which increases the deposition rate to 4.8 ± 0.2 Hz s−1. When the film approaches the desired thickness (2.8 μm, which corresponds to a frequency shift of ∼21,000 Hz), we terminate H2O gas deposition first [3] and continue with CO2 condensation briefly to ensure that the terminal CO2 rate did not drift significantly from the initial value (<10%). The CO2 doser is shut off at [4]. This co-deposition scheme using multiple gas dosers with QCM gravimetry allows for producing mixed ices with precisely tailored composition. This film has CO2 intimately mixed with water ice at 2.5% ± 0.1% (by number) concentration.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: (a) Spectral deconvolution of the continuum-subtracted 3.5 μm absorption (black open circles) obtained following 10 keV electron irradiation of water ice with 2.5% (by number) CO2 at 70 K. The absorption is modeled using a scaled H2O2 component (blue dashed line) from pure H2O ice irradiation, combined with three Gaussian components (magenta, olive, and cyan dashed lines) representing CHO species that have overlapping absorptions with H2O2. The first organic component, centered at 2831 cm−1 (3.53 μm; magenta dashed line), is methanol. Although specific assignments for the other two Gaussian components are uncertain, C–H stretches from other organics likely contribute to these features, adding a broadened shoulder on the long-wavelength side of the peroxide absorption. The cumulative fit (solid orange line) shows good agreement with the measured spectrum. (b) Improvement in residuals (Data − Fit) when organic components are included. The blue residual curve represents H2O2 only, while the black curve includes CHO species. The H2O2 column densities in CO2-containing ices are calculated after organic contributions (<15%) have been subtracted from the total integrated band area.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: Spectra of a ∼2.76 μm-thick H2O + 4.4% CO2 ice before (bottom, black curve) and after (top, blue curve) irradiation to a fluence of 3.1 × 1016 e− cm−2. The left inset highlights the emergence of the H2O2 feature at 2861 cm−1, analyzed as described in Section 2 and Figure 1. The right inset shows an expanded view of the mid-IR region, illustrating the formation of new CHO species absorptions at 1498, 1390, 1307, and 1016 cm−1 after irradiation. The spectra have been offset vertically for clarity.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: Fit to the 70 K destruction cross section values (solid black curve) using the empirical relation ﹩{\sigma }_{d}={\sigma }_{{d}_{0}}-{\sigma }_{{s}_{1}}(1-\exp (-{\sigma }_{{s}_{0}}{\eta }_{{\rm{C}}{{\rm{O}}}_{2}}))+{\sigma }_{{d}_{1}}({\eta }_{{\rm{C}}{{\rm{O}}}_{2}}/{\eta }_{T})﹩. The cross section decreases sharply with small amounts of CO2, as CO2 or its radiolytic by-products protect H2O2 from destruction by reacting with OH radicals to form organics, or by scavenging secondary electrons. This shielding effect (olive dashed line) is represented by the first two terms in the empirical equation. At higher CO2 abundances, the shielding effect diminishes, and the third term, representing CO2-mediated H2O2 destruction (red dashed line), becomes more significant. The parameters values used to obtain the fit are ﹩{\sigma }_{{s}_{0}}=(1.4\pm 0.2)\times 1{0}^{-17}\,{{\rm{cm}}}^{2}﹩, ﹩{\sigma }_{{s}_{1}}=(7.3\pm 0.1)\times 1{0}^{-16}\,{{\rm{cm}}}^{2}﹩, and ﹩{\sigma }_{{d}_{1}}=(2.1\pm 0.2)\times 1{0}^{-15}\,{{\rm{cm}}}^{2}﹩. The corresponding values for the 100 K data are ﹩{\sigma }_{{s}_{0}}=(1.9\pm 0.2)\times 1{0}^{-17}\,{{\rm{cm}}}^{2}﹩, ﹩{\sigma }_{{s}_{1}}=(9.0\pm 0.1)\times 1{0}^{-15}\,{{\rm{cm}}}^{2}﹩, and ﹩{\sigma }_{{d}_{1}}=(7.5\pm 0.5)\times 1{0}^{-15}\,{{\rm{cm}}}^{2}﹩. The parameter ﹩{\sigma }_{{d}_{0}}﹩ is the cross section for pure water ice.
Paper: Laboratory Investigation of CO2-driven Enhancement of Radiolytic H2O2 on Europa and Other Icy Moons
Authors: Bereket D. Mamo, Ujjwal Raut, Ben D. Teolis, Trevor P. Erwin, Richard J. Cartwright, Silvia Protopapa, Kurt D. Retherford, Tom A. Nordheim
Figure caption: (a) Emergence of the 3.5 μm H2O2 feature after irradiation of a 2.8 μ m-thick pure water-ice film at 70 K with 10 keV electrons to a fluence of 1.5 × 1016 e− cm−2. A polynomial continuum (dashed blue curve) is subtracted from the irradiated spectra to obtain the asymmetric absorption (blue shaded region). (b) Same as panel (a), but for water-ice film of similar thickness that contains 2.5% CO2. The integrated area of the continuum-subtracted absorption is >2.5× larger for the CO2-doped film relative to that of pure water ice. The spectra have been vertically shifted for clarity.
Paper: Particle Accretion in Microgravity. I. Particle Sizes and Bulk Densities
Authors: Akbar D. Whizin, Daniel D. Durda, Constantine C. C. Tsang, Stanley G. Love
Figure caption: Aggregates and individual particles of sugar ((a) and (b)) and other materials (c) including coffee grounds that were allowed to float for several hours on board the ISS in Don Pettit’s experiments (figures from S. G. Love et al. 2014).