adsabs/AstroCLIMB huggingface dataset:
Paper: Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth
Authors: Nicholas F. Wogan, David C. Catling, Kevin J. Zahnle, Roxana Lupu
Figure caption: Methane photochemical lifetime in postimpact atmospheres. The plot shows the CH4 mixing ratio and production and loss as a function of altitude 10,000 yr after the steam atmosphere has condensed to an ocean following the 1.58 × 1021 kg impact described in Figure 6. The CH4 is primarily destroyed by photolysis but reforms efficiently in the H2-rich atmosphere from CH3 + H + M → CH4 + M. The result is a 4.8 million yr CH4 photochemical lifetime. The CH4 only persists in the atmosphere for about 1 million yr because H2 escapes to space in this amount of time, which inhibits CH4 recombination.
Paper: Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth
Authors: Nicholas F. Wogan, David C. Catling, Kevin J. Zahnle, Roxana Lupu
Figure caption: Identical to Figure 9 in the main text but assumes postimpact H2 generation if governed by model 1B described in Figure 2.
Paper: Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth
Authors: Nicholas F. Wogan, David C. Catling, Kevin J. Zahnle, Roxana Lupu
Figure caption: The HCN production from lightning for the same simulations and time period shown in Figure 7. The calculations use methods described in Chameides & Walker (1981) assuming modern Earth’s lightning dissipation rate (9.8 × 10−9 J cm−2 s−1) and a 2250 K HCN freeze-out temperature. The HCN production from lightning is small compared to what is achievable with photochemistry.
Paper: Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth
Authors: Nicholas F. Wogan, David C. Catling, Kevin J. Zahnle, Roxana Lupu
Figure caption: Identical to Figure 4 in the main text but assumes postimpact H2 generation if governed by model 1B described in Figure 2.
Paper: Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth
Authors: Nicholas F. Wogan, David C. Catling, Kevin J. Zahnle, Roxana Lupu
Figure caption: Identical to Figure 5 in the main text but assumes postimpact H2 generation if governed by model 1B described in Figure 2.
Paper: Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth
Authors: Nicholas F. Wogan, David C. Catling, Kevin J. Zahnle, Roxana Lupu
Figure caption: Deposition velocity of HCN caused by hydrolysis in the ocean. The calculations use Equation (C17) assuming v over = 1.2 × 10−5 cm s−1, z s = 104 cm, and z d = 4 × 105 cm.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: Apparent c-band (cyan) magnitude along the ATLAS trail. Time and trail length are measured from shutter closure, assuming the rate of motion calculated in this work. Regions of the trail less than 8 pixels from the center of a star have been masked out.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: An illustration of the Earth’s shadow’s alignment at the time of image capture. The umbral shadow is shown in dark gray. The penumbral shadow is imperceptibly larger than the umbral at such close proximity to the Earth. The gray circle is the upper “limit” of LEO orbits at H LEO = 2000 km. The red wedge is the volume of space covered by the image. The irregular green area is the predicted uncertainty of the object. The numbered blue lines in both the main image and inset represent the motions of all tracked artificial objects in the field of view of the image, with their NORAD TLE numbers. Within the field of the image, any object inside the LEO limit, and substantially further, is in the Earth’s shadow and would not be visible in the image. Only three tracked objects are within the image field, and only one of them (26583) is outside the Earth’s shadow and is visible. This object is evident in the ATLAS image reproduced in Figure 2.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: The cross-sectional width of the ATLAS image trail. In the upper panel, the best-fit Gaussian cross section of the entire trail with respect to a hypothetical straight line between the trail’s start and end is shown in dark green. This fit has a FWHM of 2.58 pixels. However, the trail has a slight curvature that broadens this distribution. When the trail is broken up into short segments and fit individually (light green lines), these show a smaller FWHM (2.37 ± 0.31), which is consistent with the stars in the image. This result indicates that the trail is not close enough to the telescope to undergo any defocusing. In the lower panel, cross sections of nearby stars, sliced along the same direction used to construct the trail cross sections, are shown for comparison.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: Height at maximum luminosity as a function of entry velocity for meter-sized impactors. The USG 20200918 fireball is shown as a red star. The dotted lines are constant values of dynamic pressure and provide a proxy for strength. Black squares are meter-sized meteorite dropping fireballs, while inverted triangles represent ground-based fireball network observations of meter-sized objects (Brown et al. 2015). Open circles are from the CNEOS-JPL fireball database. See text for description of blue lines associated with various fireball types using model interpretation.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: Infrasound detected at the four-element IS59 array in Hawaii from the USG 20200918 bolide. The bolide signal is centered around 10:30:00 UTC. Shown is the bandpassed waveform between 0.1 and 2 Hz (bottom plot) in units of pascals for element 4 of the array. Here, we have used 60 s windows with 50% overlap and found the best beam correlation (top plot), array trace velocity (second from top), and apparent back azimuth (third plot from top). The main air-wave arrival is highlighted by the vertical green bar. From I59 the great circle back azimuth to the USG fireball location is 218°, while the average observed back azimuth of the signal across all frequencies centered at 10:30:00 UT is 219.5 ± 2.9°.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: Illustration of the meteoroid’s Apollo Earth-crossing orbit. The inner meteoroid orbit is that derived directly by FROSTI from the USG event for use in the search for precovery images. The outer orbit is the refined orbit computed from the best-fit trajectory using both the USG observation and the object streak on the ATLAS image. The planets and meteoroids are positioned 1 month prior to the fireball event. The impact point of Earth and the meteoroid is marked with the asterisk.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: Marginal probability distributions (in gray) from one of the parameter fitting runs. The blue points with horizontal uncertainty bars show the median values with their 1σ uncertainties. The fitted parameters are displayed as differences from the nominal USG values and from a nominal absolute magnitude H of 32.5. The blue curves show the cumulative probability distributions.
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: A histogram of Earth satellite perigee values, from the Union of Concerned Scientists Database (retrieved 2021 May 13).
Paper: Preatmospheric Detection of a Meter-sized Earth Impactor
Authors: David L. Clark, Paul A. Wiegert, Peter G. Brown, Denis Vida, Aren Heinze, Larry Denneau
Figure caption: The observed fireball light curve as a function of height as measured by USG sensors (blue) and by the GLM instrument (orange). The GLM light curve has been computed assuming a 6000 K blackbody following the procedure of Jenniskens et al. (2018). Also shown is the light-curve model fit (see text for details). Individual fragment light curves are shown as green hatched lines, associated dust released as erosion as purple hatched lines, and the main fragment light curve is shown as a blue solid line.
Paper: Orbits and Masses of the Small Satellites of Pluto
Authors: Simon B. Porter, Robin M. Canup
Figure caption: Residuals for the nominal solution given in Table 3 vs. the HST (left) and New Horizons data sets (right). The horizontal dotted line is at χ 2 = 1, and the vertical dashed line is the New Horizons flyby. Note that the highest residuals are for Styx and Kerberos in all the HST data and for Nix and Hydra in the early LORRI observations; these correspond to low-S/N observations that often have excessive error beyond what would be expected from the resolution of the camera owing to faint background sources (Pluto was in a dense star field for all these observations). By combining the HST and New Horizons data sets, we were able to combine the best Nix and Hydra constraints from HST with the strongest Styx and Kerberos constraints from New Horizons. The reduced χ 2 for each body for this particular solution, averaging across all the data sets (including those with low S/N), are 0.376 for Nix, 0.331 for Hydra, 0.596 for Kerberos, and 0.676 for Styx; see the text for more details.
Paper: First Optical Constants of Laboratory-generated Organic Refractory Materials (Tholins) Produced in the NASA Ames COSmIC Facility from the Visible to the Near Infrared (0.4–1.6 μm): Application to Titan’s Aerosols
Authors: Ella Sciamma-O'Brien, Ted L. Roush, Pascal Rannou, David Dubois, Farid Salama
Figure caption: Radiance factor observed with VIMS (images 1702505209_1 taken 2011 December 13) between 0.4 and 1.6 μm, during flyby T79, above the Huygens landing site (red dots + thin red lines for the uncertainty, mostly visible below 0.8 μm). The thick blue curves correspond to the best fit of the data obtained for D  f  = 2.0 with the optical indices of the tholin samples produced at −700 V and modified by X  k  (Figure 5, left) to fit the radiance factor between 0.4 and 0.7 μm. The thin blue curves correspond to the best fits of the data calculated up to 1.6 μm for three values of the surface albedo, A  s  = 0 (dashed line), A  s  = 0.08 (solid line), and A  s  = 0.16 (dotted line). The black line corresponds to the best fit obtained for D  f  = 2.3 from 0.4 to 0.7 μm with the same optical indices modified by X  k  (Figure 5, right).
Paper: First Optical Constants of Laboratory-generated Organic Refractory Materials (Tholins) Produced in the NASA Ames COSmIC Facility from the Visible to the Near Infrared (0.4–1.6 μm): Application to Titan’s Aerosols
Authors: Ella Sciamma-O'Brien, Ted L. Roush, Pascal Rannou, David Dubois, Farid Salama
Figure caption:   2  map as a function of the haze scaling factor F  h  and the imaginary part of the refractive index scaling factor X  k   for the two fractal dimensions considered in this work, D  f  = 2.0 (left) and D  f  = 2.3 (right), when considering the optical constants of the N2:CH4 (−700 V) in the calculations. For each map, the thin and thick contours correspond to a coarse and a fine sample of the space parameter used to produce the map, respectively. Left: For the case D  f  = 2.0, the contour labeled with “1.00” shows the region of the best fits; the other labels indicate, with increasing values, the 1σ, 2σ, and 3σ levels of confidence. The cross (“+”) indicates the values for the best fit that has been retained for this work. Right: For the case D  f  = 2.3, the large values of the χ 2 indicate poor fits and the contours have no meaning in terms of level of confidence.
Paper: Orbits and Masses of the Small Satellites of Pluto
Authors: Simon B. Porter, Robin M. Canup
Figure caption: Corner plot (Foreman-Mackey 2016) of the dynamical masses of the small satellites of Pluto derived from the family of solutions produced by the MCMC model. Histograms on top show the probability distributions for the masses of each object, while contour plots show the probability covariance between the masses. In the contour plots, all individual MCMC solutions are overplotted, with each solution being equally likely. Darker (lighter) regions have a higher (lower) density of such solutions and thus show regions of higher (lower) overall likelihood. Contour lines for solution density show the shape of the covariance between the parameters. The mean of all MCMC solutions provides the expectation value of the solution set, and the standard deviation provides the uncertainty, with values given in the upper right corner. Both Nix and Hydra have well-defined masses, and by combining these with the volumes from Porter et al. (2021), we find that Nix and Hydra have densities close to 1.1 g cm−3, substantially lower than the densities of Pluto and Charon. The Kerberos and Styx masses remain poorly constrained, with 1σ upper limits for their masses given above.
Paper: First Optical Constants of Laboratory-generated Organic Refractory Materials (Tholins) Produced in the NASA Ames COSmIC Facility from the Visible to the Near Infrared (0.4–1.6 μm): Application to Titan’s Aerosols
Authors: Ella Sciamma-O'Brien, Ted L. Roush, Pascal Rannou, David Dubois, Farid Salama
Figure caption: Normalized extinction of the haze between 1 and 2 μm as observed with a solar occultation made by VIMS (T53) at wavelengths corresponding to the methane window (blue circles). The blue line corresponds to the best fit of the occultation data obtained for the case of aggregates with a fractal dimension D  f  = 2.0, with N ≈ 1 million monomers per aggregate, and with the assumption of a constant value of the refractive index for the haze material (Rannou et al. 2022). This is not consistent with the Descent Imager/Spectral Radiometer (DISR) on board Huygens (Tomasko et al. 2008). The pink line corresponds to the fit obtained for aggregates with D  f  = 2.0 and a number of monomers per aggregate N ≈ 3000, that is, a case consistent with observations of DISR (Tomasko et al. 2008) but not with VIMS occultations. The cyan and light green curves show how the extinction changes when the imaginary part of the refractive index varies with wavelength following a power law.
Paper: First Optical Constants of Laboratory-generated Organic Refractory Materials (Tholins) Produced in the NASA Ames COSmIC Facility from the Visible to the Near Infrared (0.4–1.6 μm): Application to Titan’s Aerosols
Authors: Ella Sciamma-O'Brien, Ted L. Roush, Pascal Rannou, David Dubois, Farid Salama
Figure caption: Average real index of refraction n determined for solid samples formed from plasma chemistry at low temperature in N2:CH4 (green, orange, red) N2:CH4:C2H2 (purple), and Ar:CH4 (blue) gas mixtures. The shaded envelopes of 1σ uncertainty were obtained by measuring the samples at different locations. Also shown are experimental n values from Khare et al. (1984, black dots), Mahjoub et al. (2014, dashed pink line), and He et al. (2022, dashed brown line), as well as modeled n values of Titan aerosols derived from Cassini VIMS observations by Lavvas et al. (2010, gray triangles). The optical constants data for the COSmIC samples shown in this figure are available. (The data used to create this figure are available.)
Paper: First Optical Constants of Laboratory-generated Organic Refractory Materials (Tholins) Produced in the NASA Ames COSmIC Facility from the Visible to the Near Infrared (0.4–1.6 μm): Application to Titan’s Aerosols
Authors: Ella Sciamma-O'Brien, Ted L. Roush, Pascal Rannou, David Dubois, Farid Salama
Figure caption: Average imaginary index of refraction k determined for solid samples formed from plasma chemistry at low temperature in N2“CH4 (green, orange, red) N2:CH4:C2H2 (purple), and Ar:CH4 (blue) gas mixtures. The shaded envelope of 1σ uncertainty was obtained by measuring the samples at different locations. Also shown are experimental k values from Khare et al. (1984, black dots), Mahjoub et al. (2014, dashed pink line), and He et al. (2022, dashed brown line), as well as modeled k values of Titan’s aerosols derived from Cassini VIMS observations by Lavvas (2010, gray triangles) and Rannou et al. (2010, gray circles). The optical constants data for the COSmIC samples shown in this figure are available (see Figure 3).
Paper: First Optical Constants of Laboratory-generated Organic Refractory Materials (Tholins) Produced in the NASA Ames COSmIC Facility from the Visible to the Near Infrared (0.4–1.6 μm): Application to Titan’s Aerosols
Authors: Ella Sciamma-O'Brien, Ted L. Roush, Pascal Rannou, David Dubois, Farid Salama
Figure caption: Left: Filmetrics F40 microscope image of the N2:CH4 (−1000 V) tholin sample produced in COSmIC. The bright circular region shows the uniformity of the sample across the 1 mm × 1 mm sampled area. The dark central spot (50 μm in diameter) is where the reflectance spectrum was measured. Right: Reflectance measurement (blue) and best fit (red) used to determine n, k, and the thickness d of the sample.
Paper: Review and Revision of the Lunar Cratering Chronology—Lunar Timescale Part 2
Authors: Stephanie C. Werner, Benjamin Bultel, Tobias Rolf
Figure caption: Several cratering-chronology models for cumulative-crater frequencies with diameter D greater or equal to 1 km. Here, we display only the calibration points from Neukum (1983) using black crosses. For defining their models, Marchi et al. (2009); Morbidelli et al. (2012, 2018), Werner et al. (2014) reinterpreted existing crater size–frequency measurements by Neukum (1983), while Hartmann et al. (2007), Robbins (2014) collected their own crater size–frequency measurements to provide calibration points.
Paper: Review and Revision of the Lunar Cratering Chronology—Lunar Timescale Part 2
Authors: Stephanie C. Werner, Benjamin Bultel, Tobias Rolf
Figure caption: Modeled distribution of basin ejecta across the lunar surface assuming basin diameters suggested by Neumann et al. (2015). Pentagrams indicate the six Apollo sampling sites, while hexagrams indicate the three Luna sampling sites, and the square indicates the Chang’E 5 sampling site. The distribution is representative once basin formation has ceased (i.e., after the Orientale formation), but does not account for subsequent resurfacing due to lava emplacement that formed the maria.
Paper: Review and Revision of the Lunar Cratering Chronology—Lunar Timescale Part 2
Authors: Stephanie C. Werner, Benjamin Bultel, Tobias Rolf
Figure caption: Crater statistics for the Chang’E 5 landing area. (a) Counting unit with craters, the star marks the actual landing site. (b) The respective crater size–frequency distribution and the saturation empirical equilibrium (gray solid line, after Hartmann 1984).
Paper: Spatial Distribution of Glycine and Aspartic Acid in Rapidly Frozen Brines Relevant to Enceladus
Authors: Tuan H. Vu, Robert Hodyss, Paul V. Johnson, Morgan L. Cable
Figure caption: Pairwise correlation plots between the various components in the frozen aspartic acid–brine system, constructed from the Raman maps shown in Figure 5. The green line in each panel represents a linear fit of the displayed data (included to guide the eye).
Paper: Equatorial Waves and Superrotation in the Stratosphere of a Titan General Circulation Model
Authors: Neil T. Lewis, Nicholas A. Lombardo, Peter L. Read, Juan M. Lora
Figure caption: Criterion for barotropic instability plotted as zero contours for ﹩\partial \overline{Q}/\partial \vartheta {| }_{\theta }﹩ (see text). Contours are shown for a range of pressures indicated in the legend.
Paper: Equatorial Waves and Superrotation in the Stratosphere of a Titan General Circulation Model
Authors: Neil T. Lewis, Nicholas A. Lombardo, Peter L. Read, Juan M. Lora
Figure caption: Froude number as in Wang & Mitchell (2014), indicating the ratio of the Kelvin wave frequency to the Rossby wave frequency (see Equation (17) and accompanying text for details). Lines are shown for different ranges of L s, indicated in the legend.
Paper: Col-OSSOS: Evidence for a Compositional Gradient Inherited from the Protoplanetary Disk?
Authors: Michaël Marsset, Wesley C. Fraser, Megan E. Schwamb, Laura E. Buchanan, Rosemary E. Pike, Kathryn Volk, Nuno Peixinho, Susan Benecchi, Michele T. Bannister, Nicole J. Tan, J. J. Kavelaars
Figure caption: Orbital inclinations vs. spectral properties of the BrightIR (gray circles) and FaintIR (red squares) classes of TNOs, for the complete set of objects from the Col-OSSOS, H/WTSOSS, and MBOSS+ surveys. The spectral properties shown here include (left) the visible spectral slopes, (middle) the NIR spectral slopes, and (right) the PC1 values from the reprojection of the optical-NIR color–color plot (Section 2.2). The gray and red lines are y∣x linear fits to the BrightIR and FaintIR classes, respectively, with the darker and lighter shades corresponding to cold classicals being included and not being included in the data set, respectively. We find that BrightIR objects with lower spectral slopes and lower PC1 values are preferentially found on higher-inclination orbits with respect to their counterparts with larger spectral slopes and PC1 values. On the other hand, FaintIR objects with lower spectral slopes and lower PC1 values preferentially have lower orbital inclinations compared to FaintIR objects with larger spectral slopes and PC1 values. However, in the case of FaintIR objects this trend is driven by a very small number of objects (Section 3.2).
Paper: Col-OSSOS: Evidence for a Compositional Gradient Inherited from the Protoplanetary Disk?
Authors: Michaël Marsset, Wesley C. Fraser, Megan E. Schwamb, Laura E. Buchanan, Rosemary E. Pike, Kathryn Volk, Nuno Peixinho, Susan Benecchi, Michele T. Bannister, Nicole J. Tan, J. J. Kavelaars
Figure caption: Orbital distribution of the analyzed data set, divided into dynamical (left) and spectral classes (right). Lines of constant perihelion are plotted for q = 30 au and q = 40 au in the eccentricity plot. Mean-motion resonances (MMRs) with Jupiter are shown as vertical dotted lines. The 9:5, 11:6, and 15:8, located in the classical belt between the 7:4 and 2:1 MMRs, are not labeled for better readability. See companion paper by Pike et al. (2017) for a detailed analysis of the resonant populations in the Col-OSSOS survey. The FaintIR-dominated population of dynamically quiescent cold classicals is approximately located between semimajor axis values of 42 < a < 47 au and inclinations i < 6°. The scattering disk extends to large semimajor axis and is dominated by BrightIR objects (objects with q < 26.0 au were rejected from our data set for reasons explained in Section 2.1). The colored intervals along the y-axis (right panels) correspond to the mean value of the orbital parameter in the FaintIR (red) and BrightIR (black) classes, plus and minus the uncertainty on the mean (﹩\sigma /\sqrt{N}﹩). The darker and lighter shades correspond to cold classicals being included and not being included in the class, respectively (see Section 2.1 for our adopted definition of cold classicals). On average, BrightIR TNOs are found on dynamically more excited (inclined and eccentric) orbits and have lower perihelion values compared to FaintIR TNOs, whether or not cold classicals are considered in the data set.