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The Distribution of Highly Red-sloped Asteroids in the Middle and Outer Main Belt Planet. Sci. J. Pub Date : 2024-03-27 Oriel A. Humes, Cristina A. Thomas, Lauren E. McGraw
Red (S > 10%/0.1 μm) spectral slopes are common among Centaurs and trans-Neptunian objects (TNOs) in the outer solar system. Interior to and co-orbital with Jupiter, the red (S ∼ 10%/0.1 μm) slopes of D-type main-belt and Jupiter Trojan asteroids are thought to reflect their hypothesized shared origin with TNOs beyond the orbit of Jupiter. In order to quantify the abundance of red-sloped asteroids
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Encounter Circumstances of Asteroid 99942 Apophis with the Catalog of Known Asteroids Planet. Sci. J. Pub Date : 2024-03-27 Paul Wiegert, Benjamin Hyatt
Asteroid 99942 Apophis will pass near Earth in 2029 April. Expected to miss our planet by a safe margin, that could change if Apophis's path were perturbed by a collision with another asteroid in the interim. Though the statistical chance of such a collision is minuscule, the high risk associated with Apophis motivates us to examine even this very unlikely scenario. In this work, we identify encounters
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Postperihelion Cometary Activity on the Outer Main-belt Asteroid 2005 XR132 Planet. Sci. J. Pub Date : 2024-03-26 Yu-Chi Cheng, Bryce T. Bolin, Michael S. P. Kelley, D. Bodewits, Quanzhi Ye, Christoffer Fremling, Zhong-Yi Lin, Ya-Lin Wu, Reed L. Riddle, Wing-Huen Ip, Steven L. Groom, Russ R. Laher
We report comet-like activity on the outer main-belt asteroid 2005 XR132 discovered by the Lulin One-meter Telescope in early 2021 April. A series of follow-up observations were triggered to characterize the morphology and brightness variation of 2005 XR132. Long-term photometric data of the 2020 perihelion return reveal a 2 mag fading in 120 days, starting 20 days postperihelion, attributed to decreased
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Lessons Learned from NASA’s DART Impact about Disrupting Rubble-pile Asteroids Planet. Sci. J. Pub Date : 2024-03-26 S. D. Raducan, M. Jutzi, C. C. Merrill, P. Michel, Y. Zhang, M. Hirabayashi, A. Mainzer
We present a series of numerical simulations using a shock physics smoothed particle hydrodynamics code, investigating energetic impacts on small celestial bodies characterized by diverse internal structures, ranging from weak and homogeneous compositions to rubble-pile structures with varying boulder volume packing. Our findings reveal that the internal structure of these rubble-pile bodies significantly
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Lunar Boulder Fields as Indicators of Recent Tectonic Activity Planet. Sci. J. Pub Date : 2024-03-22 Cole Nypaver, Thomas Watters, Bradley Thomson, Ali Bramson, Joshua Cahill, Jacklyn Clark, Catherine Elder, Caleb Fassett, Gareth Morgan, Santa Lucía Pérez Cortés, Tyler Powell
Wrinkle ridges are the predominant tectonic structure on the nearside lunar maria. Although lunar wrinkle ridge formation began as early as ∼3.9–4.0 Ga, recent investigations have identified wrinkle ridges in the lunar maria that were tectonically active as recently as the Copernican period of lunar geologic history. Some of those geologically young wrinkle ridges were identified by the presence of
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Juno’s JunoCam Images of Europa Planet. Sci. J. Pub Date : 2024-03-21 C. J. Hansen, M. A. Ravine, P. M. Schenk, G. C. Collins, E. J. Leonard, C. B. Phillips, M. A. Caplinger, F. Tosi, S. J. Bolton, Björn Jónsson
On 2022 September 29 the Juno spacecraft passed Europa at 355 km, the first close pass since the Galileo flyby in 2000. Juno’s visible-light imager, JunoCam, collected four images, enabling cartographic, topographic, and surface geology analysis. The topography along the terminator is consistent with previously reported features that may indicate true polar wander. A bright band was discovered, and
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SpuBase: Solar Wind Ion Sputter Database for Modeling Purposes Planet. Sci. J. Pub Date : 2024-03-21 Noah Jäggi, Herbert Biber, Johannes Brötzner, Paul Stefan Szabo, Andreas Mutzke, Jonathan Gasser, Friedrich Aumayr, Peter Wurz, André Galli
We supply the modelers with a database, SpuBase (doi:10.5281/zenodo.10783295), that is based on the latest approach for obtaining solar wind ion sputter yields in agreement with experimental sputter data outlined in Jäggi et al. We include an overview of sputter results for typical Lunar and Hermean surfaces. To obtain total sputter yields for any given surface, we perform a mass balance of individual
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Parent Volatile Outgassing Associations in Cometary Nuclei: Synthesizing Rosetta Measurements and Ground-based Observations Planet. Sci. J. Pub Date : 2024-03-20 Mohammad Saki, Dennis Bodewits, Boncho P. Bonev, Neil Dello Russo, Adrienn Luspay-Kuti, John W. Noonan, Michael. R. Combi, Yinsi Shou
Comets, as remnants of the solar system’s formation, vary in volatile-refractory content. In situ comet studies, such as the Rosetta mission to 67P/Churyumov–Gerasimenko, provide detailed volatile composition insights, while ground-based studies offer broader comet samples but in fewer species. Comparing 67P’s volatile correlations during the 2 yr Rosetta mission with those from remote sensing gives
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Orbital and Physical Characterization of Asteroid Dimorphos Following the DART Impact Planet. Sci. J. Pub Date : 2024-03-19 Shantanu P. Naidu, Steven R. Chesley, Nicholas Moskovitz, Cristina Thomas, Alex J. Meyer, Petr Pravec, Peter Scheirich, Davide Farnocchia, Daniel J. Scheeres, Marina Brozovic, Lance A. M. Benner, Andrew S. Rivkin, Nancy L. Chabot
The Double Asteroid Redirection Test (DART) mission impacted Dimorphos, the satellite of binary near-Earth asteroid (65803) Didymos, on 2022 September 26 UTC. We estimate the changes in the orbital and physical properties of the system due to the impact using ground-based photometric and radar observations, as well as DART camera observations. Under the assumption that Didymos is an oblate spheroid
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Noble Gas Planetology and the Xenon Clouds of Uranus Planet. Sci. J. Pub Date : 2024-03-15 Kevin Zahnle
Noble gases provide tracers of cosmic provenance that are accessible to a future Uranus atmospheric probe. Argon and krypton are expected to be well mixed on Uranus with respect to H2 and He, although condensation at the winter pole may be possible. The Ar/H2 and Ar/Kr ratios address whether the materials accreted by Uranus resembled the extremely cold materials accreted by Jupiter’s atmosphere, whether
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A Gap in the Densities of Small Planets Orbiting M Dwarfs: Rigorous Statistical Confirmation Using the Open-source Code RhoPop Planet. Sci. J. Pub Date : 2024-03-15 J. G. Schulze, Ji Wang, J. A. Johnson, B. S. Gaudi, R. Rodriguez Martinez, C. T. Unterborn, W. R. Panero
Using mass–radius composition models, small planets (R ≲ 2 R ⊕) are typically classified into three types: iron-rich, nominally Earth-like, and those with solid/liquid water and/or atmosphere. These classes are generally expected to be variations within a compositional continuum. Recently, however, Luque & Pallé observed that potentially Earth-like planets around M dwarfs are separated from a lower-density
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Three Years of ACB Phase Function Observations from the Mars Science Laboratory: Interannual and Diurnal Variability and Constraints on Ice Crystal Habit Planet. Sci. J. Pub Date : 2024-03-15 Alex C. Innanen, Brittney A. Cooper, Conor W. Hayes, Charissa L. Campbell, Jacob L. Kloos, Scott D. Guzewich, John E. Moores
We examine 3 yr of phase-function observations of water-ice clouds taken during the Aphelion Cloud Belt season by the Mars Science Laboratory (MSL). We derive lower-bound single-scattering phase functions for Mars years (MYs) 34, 35, and 36, over a range of scattering angles from 45° to 155°, expanding on the MY 34 phase function previously derived from MSL observations using the same method. We also
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Toward Prebiotic Chemistry on Titan: Impact Experiments on Organic Haze Particles Planet. Sci. J. Pub Date : 2024-03-12 Ben K. D. Pearce, Sarah M. Hörst, Christopher J. Cline, Mark J. Cintala, Chao He, Joshua A. Sebree, Shannon M. MacKenzie, R. Terik Daly, Alexandra J. Pontefract, Cara Pesciotta
Impacts are critical to producing the aqueous environments necessary to stimulate prebiotic chemistry on Titan’s surface. Furthermore, organic hazes resting on the surface are a likely feedstock of biomolecules. In this work, we conduct impact experiments on laboratory-produced organic haze particles and haze/sand mixtures and analyze these samples for life’s building blocks. Samples of unshocked haze
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Beyond Point Masses. III. Detecting Haumea’s Nonspherical Gravitational Field Planet. Sci. J. Pub Date : 2024-03-12 Benjamin C. N. Proudfoot, Darin A. Ragozzine, William Giforos, Will M. Grundy, Mariah MacDonald, William J. Oldroyd
The dwarf planet Haumea is one of the most compelling trans-Neptunian objects to study, hosting two small, dynamically interacting satellites, a family of nearby spectrally unique objects, and a ring system. Haumea itself is extremely oblate due to its 3.9 hr rotation period. Understanding the orbits of Haumea’s satellites, named Hi’iaka and Namaka, requires detailed modeling of both satellite–satellite
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Fermi Resonance and the Quantum Mechanical Basis of Global Warming Planet. Sci. J. Pub Date : 2024-03-11 R. Wordsworth, J. T. Seeley, K. P. Shine
Although the scientific principles of anthropogenic climate change are well-established, existing calculations of the warming effect of carbon dioxide rely on spectral absorption databases, which obscures the physical foundations of the climate problem. Here, we show how CO2 radiative forcing can be expressed via a first-principles description of the molecule’s key vibrational-rotational transitions
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Pre-impact Thermophysical Properties and the Yarkovsky Effect of NASA DART Target (65803) Didymos Planet. Sci. J. Pub Date : 2024-03-11 Benjamin Rozitis, Simon F. Green, Samuel L. Jackson, Colin Snodgrass, Cyrielle Opitom, Thomas G. Müller, Ulrich C. Kolb, Steven R. Chesley, R. Terik Daly, Cristina A. Thomas, Andrew S. Rivkin
The NASA Double Asteroid Redirection Test (DART) spacecraft impacted the secondary body of the binary asteroid (65803) Didymos on 2022 September 26 and altered its orbit about the primary body. Before the DART impact, we performed visible and mid-infrared observations to constrain the pre-impact thermophysical properties of the Didymos system and to model its Yarkovsky effect. Analysis of the photometric
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On the Fate of Slow Boulders Ejected after DART Impact on Dimorphos Planet. Sci. J. Pub Date : 2024-03-08 Fernando Moreno, Gonzalo Tancredi, Adriano Campo Bagatin
On 2022 September 26 23:14 UT, the NASA Double Asteroid Redirection Test spacecraft successfully impacted Dimorphos, the secondary component of the binary (65803) Didymos system, demonstrating asteroid orbit deflection for the first time. A large amount of debris, consisting of a wide size–frequency distribution of particulates (from micron-sized dust to meter-sized boulders), was released, and a long-lasting
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Modeling Atmospheric Lines by the Exoplanet Community (MALBEC) Version 1.0: A CUISINES Radiative Transfer Intercomparison Project Planet. Sci. J. Pub Date : 2024-03-08 Geronimo L. Villanueva, Thomas J. Fauchez, Vincent Kofman, Eleonora Alei, Elspeth K. H. Lee, Estelle Janin, Michael D. Himes, Jérémy Leconte, Michaela Leung, Sara Faggi, Mei Ting Mak, Denis E. Sergeev, Thea Kozakis, James Manners, Nathan Mayne, Edward W. Schwieterman, Alex R. Howe, Natasha Batalha
Radiative transfer (RT) models are critical in the interpretation of exoplanetary spectra, in simulating exoplanet climates, and when designing the specifications of future flagship observatories. However, most models differ in methodologies and input data, which can lead to significantly different spectra. In this paper, we present the experimental protocol of the Modeling Atmospheric Lines By the
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Evaluating Atmospheric and Surface Drivers for O2 Variations at Gale Crater as Observed by MSL SAM Planet. Sci. J. Pub Date : 2024-03-08 Daniel Y. Lo, Sushil K. Atreya, Michael H. Wong, Melissa G. Trainer, Heather B. Franz, Timothy H. McConnochie, Daniel Viúdez-Moreiras, Paul R. Mahaffy, Charles A. Malespin
We explore and evaluate various processes that could drive the variations in the volume mixing ratio (VMR) of atmospheric O2 observed by the quadrupole mass spectrometer (QMS) of the Sample Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) Curiosity rover. First reported by Trainer et al. (), these ∼20% variations in the O2 VMR on a seasonal timescale over Mars Years 31–34
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Dynamic Secondary Illumination in Permanent Shadows within Artemis III Candidate Landing Regions Planet. Sci. J. Pub Date : 2024-03-07 Prasun Mahanti, Jean-Pierre Williams, Mark S. Robinson, Robert Wagner, Erwan Mazarico, Megan Henriksen, Holly Brown, Nandita Kumari
Investigations that can be conducted at the Artemis III candidate landing regions will benefit from the knowledge of the thermal environment within permanently shadowed regions (PSRs). Within PSRs, secondary illumination controls the surface temperature, varying diurnally and seasonally, affecting the stability and concentration of volatiles cold-trapped within the PSRs. In this case study, we characterize
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Can Neptune’s Distant Mean Motion Resonances Constrain Undiscovered Planets in the Solar System? Lessons from a Case Study of the 9:1 Resonance Planet. Sci. J. Pub Date : 2024-03-07 Matthew W. Porter, David W. Gerdes, Kevin J. Napier, Hsing Wen Lin, Fred C. Adams
Recent observational surveys of the outer solar system provide evidence that Neptune's distant n:1 mean motion resonances may harbor relatively large reservoirs of trans-Neptunian objects (TNOs). In particular, the discovery of two securely classified 9:1 resonators, 2015 KE172 and 2007 TC434, by the Outer Solar System Origins Survey is consistent with a population of order 104 such objects in the
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Revealing Callisto’s Carbon-rich Surface and CO2 Atmosphere with JWST Planet. Sci. J. Pub Date : 2024-03-06 Richard J. Cartwright, Geronimo L. Villanueva, Bryan J. Holler, Maria Camarca, Sara Faggi, Marc Neveu, Lorenz Roth, Ujjwal Raut, Christopher R. Glein, Julie C. Castillo-Rogez, Michael J. Malaska, Dominique Bockelée-Morvan, Tom A. Nordheim, Kevin P. Hand, Giovanni Strazzulla, Yvonne J. Pendleton, Katherine de Kleer, Chloe B. Beddingfield, Imke de Pater, Dale P. Cruikshank, Silvia Protopapa
We analyzed spectral cubes of Callisto’s leading and trailing hemispheres, collected with the NIRSpec Integrated Field Unit (G395H) on the James Webb Space Telescope. These spatially resolved data show strong 4.25 μm absorption bands resulting from solid-state 12CO2, with the strongest spectral features at low latitudes near the center of its trailing hemisphere, consistent with radiolytic production
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A New Database of Giant Impacts over a Wide Range of Masses and with Material Strength: A First Analysis of Outcomes Planet. Sci. J. Pub Date : 2024-03-04 Alexandre Emsenhuber, Erik Asphaug, Saverio Cambioni, Travis S. J. Gabriel, Stephen R. Schwartz, Robert E. Melikyan, C. Adeene Denton
In the late stage of terrestrial planet formation, planets are predicted to undergo pairwise collisions known as giant impacts. Here, we present a high-resolution database of giant impacts for differentiated colliding bodies of iron–silicate composition, with target masses ranging from 1 × 10−4 M ⊕ up to super-Earths (5 M ⊕). We vary the impactor-to-target mass ratio, core–mantle (iron–silicate) fraction
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One-dimensional Microphysics Model of Venusian Clouds from 40 to 100 km: Impact of the Middle-atmosphere Eddy Transport and SOIR Temperature Profile on the Cloud Structure Planet. Sci. J. Pub Date : 2024-03-01 Hiroki Karyu, Takeshi Kuroda, Takeshi Imamura, Naoki Terada, Ann Carine Vandaele, Arnaud Mahieux, Sébastien Viscardy
We conducted a simulation of H2SO4 vapor, H2O vapor, and H2SO4–H2O liquid aerosols from 40 to 100 km, using a 1D Venus cloud microphysics model based on the one detailed in Imamura & Hashimoto. The cloud distribution obtained is in good agreement with in situ observations by Pioneer Venus and remote-sensing observations from Venus Express (VEx). Case studies were conducted to investigate sensitivities
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Signatures of X-Ray-dominated Chemistry in the Spectra of Exoplanetary Atmospheres Planet. Sci. J. Pub Date : 2024-03-01 Daniele Locci, Giambattista Aresu, Antonino Petralia, Giuseppina Micela, Antonio Maggio, Cesare Cecchi-Pestellini
High-energy radiation from stars impacts planetary atmospheres, deeply affecting their chemistry and providing departures from chemical equilibrium. While the upper atmospheric layers are dominated by ionizations induced by extreme-ultraviolet radiation, deeper into the atmosphere, molecular abundances are controlled by a characteristic X-ray-dominated chemistry, mainly driven by an energetic secondary
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Subsurface Thermophysical Properties of Europa’s Leading and Trailing Hemispheres as Revealed by ALMA Planet. Sci. J. Pub Date : 2024-02-29 Alexander E. Thelen, Katherine de Kleer, Maria Camarca, Alex Akins, Mark Gurwell, Bryan Butler, Imke de Pater
We present best-fit values of porosity—and the corresponding effective thermal inertiae—determined from three different depths in Europa’s near-subsurface (∼1–20 cm). The porosity of the upper ∼20 cm of Europa’s subsurface varies between 75% and 50% (Γeff ≈ 50–140 J m−2 K−1 s−1/2) on the leading hemisphere and 50%–40% (Γeff ≈ 140–180 J m−2 K−1 s−1/2) on the trailing hemisphere. Residual maps produced
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Direct N-body Simulations of Satellite Formation around Small Asteroids: Insights from DART’s Encounter with the Didymos System Planet. Sci. J. Pub Date : 2024-02-28 Harrison F. Agrusa, Yun Zhang, Derek C. Richardson, Petr Pravec, Matija Ćuk, Patrick Michel, Ronald-Louis Ballouz, Seth A. Jacobson, Daniel J. Scheeres, Kevin Walsh, Olivier Barnouin, R. Terik Daly, Eric Palmer, Maurizio Pajola, Alice Lucchetti, Filippo Tusberti, Joseph V. DeMartini, Fabio Ferrari, Alex J. Meyer, Sabina D. Raducan, Paul Sánchez
We explore binary asteroid formation by spin-up and rotational disruption considering the NASA DART mission's encounter with the Didymos–Dimorphos binary, which was the first small binary visited by a spacecraft. Using a suite of N-body simulations, we follow the gravitational accumulation of a satellite from meter-sized particles following a mass-shedding event from a rapidly rotating primary. The
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Large Carbonaceous Chondrite Parent Bodies Favored by Abundance–Volatility Modeling: A Possible Chemical Signature of Pebble Accretion Planet. Sci. J. Pub Date : 2024-02-28 Jeremy W. Boyce, Francis M. McCubbin, Nicole Lunning, Tyler Anderson
Primitive meteorite groups such as the Vigarano, Mighei, and Karoonda carbonaceous chondrites have enigmatic patterns of elemental abundances, with moderately volatile elements—those that transition from vapor to condensate between ∼400 and ∼900 K—defining plateaus of subequal abundances despite a wide range in volatility. In detail, each group defines a plateau with distinctive nonmonotonic “chemical
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A Solution for the Density Dichotomy Problem of Kuiper Belt Objects with Multispecies Streaming Instability and Pebble Accretion Planet. Sci. J. Pub Date : 2024-02-28 Manuel H. Cañas, Wladimir Lyra, Daniel Carrera, Leonardo Krapp, Debanjan Sengupta, Jacob B. Simon, Orkan M. Umurhan, Chao-Chin Yang, Andrew N. Youdin
Kuiper Belt objects (KBOs) show an unexpected trend, whereby large bodies have increasingly higher densities, up to five times greater than their smaller counterparts. Current explanations for this trend assume formation at constant composition, with the increasing density resulting from gravitational compaction. However, this scenario poses a timing problem to avoid early melting by decay of 26Al
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Mercury’s Lobate Scarps Reveal that Polygonal Impact Craters Form on Contractional Structures Planet. Sci. J. Pub Date : 2024-02-27 Chloe B. Beddingfield, Kelsey Crane, Christian Klimczak, Richard Cartwright
Analysis of polygonal impact craters (PICs) can be used to investigate the presence and orientations of subtle and/or buried faults and fractures across the solar system that may otherwise be unobservable in spacecraft images. Although this technique has been vetted for the analysis of extensional structures, no previous work has investigated if PICs also form on contractional thrust faults. This determination
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Five Mars Years of Cloud Observations at Gale Crater: Opacities, Variability, and Ice Crystal Habits Planet. Sci. J. Pub Date : 2024-02-27 Conor W. Hayes, Jacob L. Kloos, Alex C. Innanen, Charissa L. Campbell, Haley M. Sapers, John E. Moores
We update the record of cloud opacity observations conducted by the Mars Science Laboratory (MSL) Curiosity rover to cover the first five Mars Years (MYs) of the mission (L s = 160° of MY 31 to L s = 160° of MY 36). Over the three MY period that we add to the previously analyzed two MY record, we achieve good diurnal coverage between 07:00 and 17:00 with nearly 1200 new observations. We derive a new
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The DECam Ecliptic Exploration Project (DEEP). V. The Absolute Magnitude Distribution of the Cold Classical Kuiper Belt Planet. Sci. J. Pub Date : 2024-02-27 Kevin J. Napier, Hsing Wen Lin, David W. Gerdes, Fred C. Adams, Anna M. Simpson, Matthew W. Porter, Katherine G. Weber, Larissa Markwardt, Gabriel Gowman, Hayden Smotherman, Pedro H. Bernardinelli, Mario Jurić, Andrew J. Connolly, J. Bryce Kalmbach, Stephen K. N. Portillo, David E. Trilling, Ryder Strauss, William J. Oldroyd, Chadwick A. Trujillo, Colin Orion Chandler, Matthew J. Holman, Hilke E. Schlichting
The DECam Ecliptic Exploration Project (DEEP) is a deep survey of the trans-Neptunian solar system being carried out on the 4 m Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile using the Dark Energy Camera (DECam). By using a shift-and-stack technique to achieve a mean limiting magnitude of r ∼ 26.2, DEEP achieves an unprecedented combination of survey area and depth, enabling
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The Secular Dynamical Evolution of Binary Asteroid System (65803) Didymos Post-DART Planet. Sci. J. Pub Date : 2024-02-26 Rachel H. Cueva, Jay W. McMahon, Alex J. Meyer, Daniel J. Scheeres, Masatoshi Hirabayashi, Sabina D. Raducan, Seth A. Jacobson, Colby C. Merrill
The successful impact of NASA’s DART mission with Dimorphos, the secondary body of binary asteroid system (65803) Didymos, altered the attitude, shape, and orbit of Dimorphos. In addition to perturbing the immediate short-term dynamics of the system, these changes have major implications for the binary Yarkovsky–O’Keefe–Radzievskii–Paddack (BYORP) effect and resulting long-term secular evolution. In
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Achievement of the Planetary Defense Investigations of the Double Asteroid Redirection Test (DART) Mission Planet. Sci. J. Pub Date : 2024-02-26 Nancy L. Chabot, Andrew S. Rivkin, Andrew F. Cheng, Olivier S. Barnouin, Eugene G. Fahnestock, Derek C. Richardson, Angela M. Stickle, Cristina A. Thomas, Carolyn M. Ernst, R. Terik Daly, Elisabetta Dotto, Angelo Zinzi, Steven R. Chesley, Nicholas A. Moskovitz, Brent W. Barbee, Paul Abell, Harrison F. Agrusa, Michele T. Bannister, Joel Beccarelli, Dmitriy L. Bekker, Megan Bruck Syal, Bonnie J. Buratti
NASA's Double Asteroid Redirection Test (DART) mission was the first to demonstrate asteroid deflection, and the mission's Level 1 requirements guided its planetary defense investigations. Here, we summarize DART's achievement of those requirements. On 2022 September 26, the DART spacecraft impacted Dimorphos, the secondary member of the Didymos near-Earth asteroid binary system, demonstrating an autonomously
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Sensitivity Testing of Stereophotoclinometry for the OSIRIS-REx Mission. II. Effective Observation Geometry for Digital Terrain Modeling Planet. Sci. J. Pub Date : 2024-02-21 Eric E. Palmer, John R. Weirich, Robert W. Gaskell, Diane Lambert, Tanner Campbell, Kris Drozd, Olivier S. Barnouin, Michael G. Daly, Kenneth Getzandanner, John N. Kidd, Coralie D. Adam, Dante S. Lauretta
The OSIRIS-REx mission used stereophotoclinometry (SPC) to generate digital terrain models (DTMs) of its target asteroid, Bennu. Here we present a suite of preflight tests conducted to identify the observing geometry and number of images needed to create DTMs that would enable successful navigation around and to the surface of the asteroid. We demonstrate that high-quality DTMs can be generated by
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Leveraging the Gravity Field Spectrum for Icy Satellite Interior Structure Determination: The Case of Europa with the Europa Clipper Mission Planet. Sci. J. Pub Date : 2024-02-21 G. Cascioli, E. Mazarico, A. J. Dombard, F. Nimmo
Understanding the interior structures of icy moons is pivotal for addressing their origins and habitability. We introduce an approach employing the gravity field spectrum as an additional constraint for the inversion of differentiated icy bodies’ interior structures. After developing the general methodology, we apply it to Europa, utilizing the predicted measurement capability of NASA’s Europa Clipper
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Sensitivity Testing of Stereophotoclinometry for the OSIRIS-REx Mission. I. The Accuracy and Errors of Digital Terrain Modeling Planet. Sci. J. Pub Date : 2024-02-21 Eric E. Palmer, John R. Weirich, Robert W. Gaskell, Diane Lambert, Tanner Campbell, Kris Drozd, Olivier S. Barnouin, Michael G. Daly, Kenneth Getzandanner, John N. Kidd, Coralie D. Adam, Dante S. Lauretta
Stereophotoclinometry (SPC) was the prime method of shape modeling for NASA’s OSIRIS-REx mission to asteroid Bennu. Here we describe the extensive testing conducted before launch to certify SPC as NASA Class B flight software, which not only validated SPC for operational use but also quantified the accuracy of this technique. We used a computer-generated digital terrain model (DTM) of a synthetic asteroid
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Hunting for Hydrated Minerals on Trans-Neptunian Objects Planet. Sci. J. Pub Date : 2024-02-20 Tom Seccull, Wesley C. Fraser, Dominik A. Kiersz, Thomas H. Puzia
We present new optical reflectance spectra of three potentially silicate-rich trans-Neptunian objects (TNOs). These spectra were obtained with the aim of confirming past hints and detections of λ ∼ 0.7 μm absorption features associated with the presence of iron-bearing phyllosilicates. Our new spectrum of 120216 (2004 EW95) presents clearly detected absorption features that are similar in shape to
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Lucy Observations of the DART Impact Event Planet. Sci. J. Pub Date : 2024-02-20 H. A. Weaver, J. M. Sunshine, C. M. Ernst, T. L. Farnham, S. Mottola, J. R. Spencer, S. Marchi, N. Dello Russo, O. Barnouin, H. F. Levison, K. S. Noll, C. B. Olkin, T. S. Statler, A. F. Cheng, E. G. Fahnestock, A. Fitzsimmons, M. M. Knight, J.-Y. Li, N. A. Moskovitz, C. A. Thomas, N. L. Chabot, A. S. Rivkin, Lucy Science Team, and DART Investigation Team
The Lucy LOng Range Reconnaissance Imager (L’LORRI) took 1549 images of the Didymos–Dimorphos binary system, starting 12 hr before the Double Asteroid Redirection Test (DART) impact event on 2022 September 26 and ending 24 hr after it. The Lucy imaging campaign provided pre-impact monitoring of the baseline brightness of the Didymos system, as well as intensive 1 s cadence imaging starting 3 minutes
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Surface Heterogeneity, Physical, and Shape Model of Near-Earth Asteroid (52768) 1998 OR2 Planet. Sci. J. Pub Date : 2024-02-20 Maxime Devogèle, Anna McGilvray, Eric MacLennan, Courteney Monchinski, Sean E. Marshall, Dylan Hickson, Anne Virkki, Jon D. Giorgini, Lyu Abe, David Augustin, Amadeo Aznar-Macías, Philippe Baudouin, Raoul Behrend, Philippe Bendjoya, Zouhair Benkhaldoun, Josep Bosch, Alberto Cellino, Joseph Chatelain, Marc Deldem, Marin Ferrais, Rui Goncalves, Gerard Houdin, Marek Husárik, Emmanuel Jehin, Teddy Kareta
On 2020 April 29, the near-Earth object (52768) 1998 OR2 experienced a close approach to Earth at a distance of 16.4 lunar distances (LD). 1998 OR2 is a potentially hazardous asteroid of absolute magnitude H = 16.04 that can currently come as close to Earth as 3.4 LD. We report here observations of this object in polarimetry, photometry, and radar. Our observations show that the physical characteristics
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Electrostatic Dust Analyzer for Dust Transport Measurements on the Lunar Surface Planet. Sci. J. Pub Date : 2024-02-20 X. Wang, M. Horanyi, C. Fisher, L. Eberwein, J. Deca, S. Knappmiller, D. Hansen, Z. Levin, R. Wing, D. Summers, W. Cole, P. Buedel, J. Drouet, S. Tucker, I. Garrick-Bethell
Lunar dust charging and transport is a more than five-decade-old problem. A high-fidelity and flight-qualified Electrostatic Dust Analyzer (EDA) has been developed to measure the charge, velocity, mass (size), and flux of electrostatically lofted dust particles on the lunar surface. Recent laboratory findings have greatly advanced our fundamental understanding of the dust-charging and -lofting mechanisms
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Gravity Investigation to Characterize Enceladus's Ocean and Interior Planet. Sci. J. Pub Date : 2024-02-14 Antonio Genova, Marzia Parisi, Anna Maria Gargiulo, Flavio Petricca, Simone Andolfo, Tommaso Torrini, Edoardo Del Vecchio, Christopher R. Glein, Morgan L. Cable, Cynthia B. Phillips, Nicholas E. Bradley, Ricardo L. Restrepo, Declan M. Mages, Alessandra Babuscia, Jonathan I. Lunine
A key objective for the future exploration of the icy moon Enceladus is the characterization of the habitable conditions in its internal ocean. Radio science instrumentation on board a spacecraft in a low-altitude orbit about Enceladus would enable gravity measurements that are fundamental to providing constraints on its internal structure. We present here the concept of operations and expected results
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Measurability of the Heliocentric Momentum Enhancement from a Kinetic Impact: The Double Asteroid Redirection Test (DART) Mission Planet. Sci. J. Pub Date : 2024-02-14 Rahil Makadia, Steven R. Chesley, Davide Farnocchia, Shantanu P. Naidu, Damya Souami, Paolo Tanga, Kleomenis Tsiganis, Masatoshi Hirabayashi, Siegfried Eggl
The NASA Double Asteroid Redirection Test (DART) has demonstrated the capability of successfully conducting kinetic impact-based asteroid deflection missions. The changes in the Didymos–Dimorphos mutual orbit as a result of the DART impact have already been measured. To fully assess the heliocentric outcome of deflection missions, the heliocentric momentum enhancement parameter, β ⊙, needs to be determined
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Inferring the CO2 Abundance in Comet 45P/Honda-Mrkos-Pajdušáková from [O i] Observations: Implications for the Source of Icy Grains in Cometary Comae Planet. Sci. J. Pub Date : 2024-02-14 Mikayla R. Huffman, Adam J. McKay, Anita L. Cochran
The study of cometary composition is important for understanding our solar system's early evolutionary processes. Carbon dioxide (CO2) is a common hypervolatile in comets that can drive activity but is more difficult to study than other hypervolatiles owing to severe telluric absorption. CO2 can only be directly observed from space-borne assets. Therefore, a proxy is needed to measure CO2 abundances
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Understanding the Dust Environment at Mercury: From Surface to Exosphere Planet. Sci. J. Pub Date : 2024-02-12 Harald Krüger, Michelle S. Thompson, Masanori Kobayashi, Valeria Mangano, Martina Moroni, Anna Milillo, Lindsay P. Keller, Sho Sasaki, Joe Zender, Deborah Domingue, Johannes Benkhoff, André Galli, François LeBlanc, Go Murakami, Menelaos Sarantos, Daniel W. Savin
We provide an overview of our understanding of the dust environment at Mercury and the role that dust plays in shaping the planet's surface and exosphere. Our understanding of the role that dust impacts play in the generation of Mercury's atmosphere has evolved considerably with continued analysis of results from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission
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Detection of Molecular H2O on Nominally Anhydrous Asteroids Planet. Sci. J. Pub Date : 2024-02-12 Anicia Arredondo, Margaret M. McAdam, Casey I. Honniball, Tracy M. Becker, Joshua P. Emery, Andrew S. Rivkin, Driss Takir, Cristina A. Thomas
We used the FORCAST instrument on SOFIA to obtain mid-infrared spectra (4.9–13.7 μm) of four S-type asteroids: (7) Iris, (11) Parthenope, (18) Melpomene, and (20) Massalia. Three of these four silicate-rich asteroids (Iris, Melpomene, and Massalia) were observed to have 3 μm features indicative of hydration by McAdam et al. We report a detection of a 6 μm feature that is unambiguously attributed to
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Photometry of the Didymos System across the DART Impact Apparition Planet. Sci. J. Pub Date : 2024-02-07 Nicholas Moskovitz, Cristina Thomas, Petr Pravec, Tim Lister, Tom Polakis, David Osip, Theodore Kareta, Agata Rożek, Steven R. Chesley, Shantanu P. Naidu, Peter Scheirich, William Ryan, Eileen Ryan, Brian Skiff, Colin Snodgrass, Matthew M. Knight, Andrew S. Rivkin, Nancy L. Chabot, Vova Ayvazian, Irina Belskaya, Zouhair Benkhaldoun, Daniel N. Berteşteanu, Mariangela Bonavita, Terrence H. Bressi, Melissa
On 2022 September 26, the Double Asteroid Redirection Test (DART) spacecraft impacted Dimorphos, the satellite of binary near-Earth asteroid (65803) Didymos. This demonstrated the efficacy of a kinetic impactor for planetary defense by changing the orbital period of Dimorphos by 33 minutes. Measuring the period change relied heavily on a coordinated campaign of lightcurve photometry designed to detect
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Numerical Simulations of (10199) Chariklo’s Rings with a Resonant Perturber Planet. Sci. J. Pub Date : 2024-02-06 Amanda A. Sickafoose, Mark C. Lewis
The discovery of two thin rings around the ∼ 250 km sized Centaur Chariklo was the first of its kind, and their formation and evolutionary mechanisms are not well understood. Here, we explore a single shepherd satellite as a mechanism to confine Chariklo’s rings. We also investigate the impact of such a perturber on reaccretion, which is a likely process for material located outside the Roche limit
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Clues to the Origin of Jovian Outer Irregular Satellites from Reflectance Spectra Planet. Sci. J. Pub Date : 2024-02-06 Faith Vilas, Amanda R. Hendrix
Visible/near-infrared narrowband spectroscopy (dispersion per element ∼ 6 Å) was obtained of the Jovian irregular satellites JVI Himalia, JVII Elara, JVIII Pasiphae, JIX Sinope, JX Lysithea, JXI Carme, JXII Ananke, and JXVII Callirrhoe in 2006, 2009, and 2010 using the MMT Observatory Red Channel spectrograph. These spectra sample three prograde (i = 28°), four retrograde (i = 149° and 165°), and one
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Rotationally Resolved Mid-infrared Spectroscopy of (16) Psyche Planet. Sci. J. Pub Date : 2024-02-06 Anicia Arredondo, Margaret M. McAdam, Tracy M. Becker, Linda Elkins-Tanton, Zoe Landsman, Thomas Müller
Asteroid (16) Psyche is theorized to be an exposed iron core of a primordial asteroid and is the target of the upcoming NASA Psyche mission. Recent observations of Psyche identified the presence of rotational heterogeneity, a fine-grained regolith, pyroxene, and hydrated minerals on its surface. We obtained rotationally resolved mid-infrared (MIR) spectroscopy of Psyche with the Stratospheric Observatory
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Optical Constants of Ices Important to Planetary Science from Laboratory Reflectance Spectroscopy Planet. Sci. J. Pub Date : 2024-02-05 S. C. Tegler, W. M. Grundy, M. J. Loeffler, P. D. Tribbett, J. Hanley, A. V. Jasko, H. Dawson, A. N. Morgan, K. J. Koga, A. O. Madden-Watson, M. D. Gomez, J. K. Steckloff, G. E. Lindberg, S. P. Tan, S. M. Raposa, A. E. Engle, C. L. Thieberger, D. E. Trilling
Laboratory-derived optical constants are essential for identifying ices and measuring their relative abundances on solar system objects. Almost all optical constants of ices important to planetary science come from experiments with transmission geometries. Here we describe our new experimental setup and the modification of an iterative algorithm in the literature to measure the optical constants of
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Surface Roughness at the Moon’s South Pole: The Influence of Condensed Volatiles on Surface Roughness at the Moon’s South Pole Planet. Sci. J. Pub Date : 2024-02-05 Lizeth O. Magaña, Parvathy Prem, Ariel N. Deutsch, Anna C. Martin, Heather M. Meyer, Caleb I. Fassett, Michael K. Barker, Angela Stickle, Benjamin D. Byron, Kathleen E. Mandt, Kurt D. Retherford
Condensed volatiles within lunar permanently shadowed regions are of high scientific and resource utilization importance. Volatiles remain elusive and difficult to observe directly, due to low direct solar illumination. In this work, we investigate correlations between, as well as possible effects of, condensed volatiles and surface roughness. We analyze topographic roughness at 50 m and 30–120 m baselines
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Characterization of High-priority Landing Sites for Robotic Exploration Missions in the Apollo Basin, Moon Planet. Sci. J. Pub Date : 2024-02-02 Csilla Orgel, Ines Torres, Sebastien Besse, Carolyn H. van der Bogert, Rickbir Bahia, René Prissang, Mikhail A. Ivanov, Harald Hiesinger, Gregory Michael, Jan Hendrik Pasckert, Mayssa El Yazidi, Balazs Bradak, Sebastian H. G. Walter
The South Pole–Aitken (SPA) basin is the oldest and largest visible impact structure on the Moon, making it a high priority science site for exploration missions. The 492 km diameter Apollo peak-ring basin is one of the youngest and largest basins within the SPA basin. We selected three regions of interest (ROIs) in the Apollo basin for which the landing and operational hazards are minimized and evaluated
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Atmospheric Loss in Giant Impacts Depends on Preimpact Surface Conditions Planet. Sci. J. Pub Date : 2024-02-01 Simon J. Lock, Sarah T. Stewart
Earth likely acquired much of its inventory of volatile elements during the main stage of its formation. Some of Earth’s proto-atmosphere must therefore have survived the giant impacts, collisions between planet-sized bodies, that dominate the latter phases of accretion. Here, we use a suite of 1D hydrodynamic simulations and impedance-match calculations to quantify the effect that preimpact surface
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Depth-to-diameter Ratios of Fresh Craters on the Moon and Implications for Surface Age Estimates Planet. Sci. J. Pub Date : 2024-01-31 Rachael H. Hoover, Stuart J. Robbins, Brian M. Hynek, Paul O. Hayne
The depth-to-diameter (d/D) ratios of small lunar craters (D < 400 m) can be used to determine important properties of the upper regolith, specifically material strength or thickness. The d/D is also an important component of topographic diffusion models that describe how different erosive processes influence and change the topography of a surface over time, and these models have been applied to estimate
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Modeling Linear Polarization of the Didymos–Dimorphos System before and after the DART Impact Planet. Sci. J. Pub Date : 2024-01-31 Antti Penttilä, Karri Muinonen, Mikael Granvik, Zuri Gray, Stefano Bagnulo, Ludmilla Kolokolova, Fernando Moreno
We analyze the polarization observations of the Didymos–Dimorphos system before and after the impact by the NASA Double Asteroid Redirection Test spacecraft on Dimorphos. We fit empirical polarization phase curve models and statistically confirm the discovery by Gray et al. about the degree of linear polarization of the system decreasing on the impact and remaining altered for at least 30 days post-impact
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Dust Production Rates in Jupiter-family Comets: A Two Year Study with ATLAS Photometry Planet. Sci. J. Pub Date : 2024-01-30 A. Fraser Gillan, Alan Fitzsimmons, Larry Denneau, Robert J. Siverd, Ken W. Smith, John L. Tonry, David R. Young
Jupiter-family comets (JFCs) exhibit a wide range of activity levels and mass loss over their orbits. We analyzed high-cadence observations of 42 active JFCs with the wide-field Asteroid Terrestrial-impact Last Alert System (ATLAS) in 2020–2021. We measured the dust production rates of the JFCs using the Af ρ parameter and its variation as a function of heliocentric distance. There is a tendency for
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An Updated Shape Model of Dimorphos from DART Data Planet. Sci. J. Pub Date : 2024-01-29 R. Terik Daly, Carolyn M. Ernst, Olivier S. Barnouin, Robert W. Gaskell, Hari Nair, Harrison Agrusa, Nancy L. Chabot, Andrew F. Cheng, Elisabetta Dotto, Elena Mazzotta Epifani, Raymond C. Espiritu, Tony L. Farnham, Eric E. Palmer, Petr Pravec, Andrew S. Rivkin, Dany C. Waller, Angelo Zinzi, the DART and LICIACube teams
Dimorphos was the target of the Double Asteroid Redirection Test (DART) mission. This paper summarizes the properties of an updated shape model of Dimorphos, describes the differences between the updated shape model and an earlier version published by Daly, Ernst, Barnouin et al. (doi:10.1038/s41586-023-05810-5), summarizes the data products associated with this model, and explains where the products
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Organic Hazes as a Source of Life’s Building Blocks to Warm Little Ponds on the Hadean Earth Planet. Sci. J. Pub Date : 2024-01-29 Ben K. D. Pearce, Sarah M. Hörst, Joshua A. Sebree, Chao He
Over 4 billion years ago, Earth is thought to have been a hazy world akin to Saturn’s moon Titan. The organic hazes in the atmosphere at this time could have contained a vast inventory of life’s building blocks and thus may have seeded warm little ponds for life. In this work, we produce organic hazes in the lab in atmospheres with high (5%) and low (0.5%) CH4 abundances and analyze the solid particles
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The Relative Effects of Surface and Subsurface Morphology on the Deflection Efficiency of Kinetic Impactors: Implications for the DART Mission Planet. Sci. J. Pub Date : 2024-01-25 Mallory E. DeCoster, Robert Luther, Gareth S. Collins, Kaiyi Dai, Thomas Davison, Dawn M. Graninger, Felix Kaufmann, Emma S. G. Rainey, Angela M. Stickle
The Double Asteroid Redirection Test (DART) mission impacted Dimorphos, the moonlet of the binary asteroid 65803 Didymos, on 2022 September 26 and successfully tested a kinetic impactor as an asteroid deflection technique. The success of the deflection was partly due to the momentum of the excavated ejecta material, which provided an extra push to change Dimorphos’s orbital period. Preimpact images