LPSC 2026- Part II

The Lunar and Planetary Science Conference continues into day 3-4, Wednesday and Thursday.

https://www.hou.usra.edu/meetings/lpsc2026/

https://www.hou.usra.edu/meetings/lpsc2026/program/

See also: Part I

Of the (large) program, here’s my small-body selections:

Wednesday, March 18, 2026

Differentiated Bodies: Petrology and Cosmochemistry

Neumann W. et al.  Revealing the Accretion Timescale of Early Solar System Planetesimals: The Case of the Parent Bodies of the CR Clan Meteorites [#1021]
Fits of thermal evolution models to the chronology of carbonaceous (C) meteorites show that accretion in the C reservoir started as early as in the non-C reservoir and produced differentiated bodies in addition to undifferentiated C chondritic ones.
Grewal D. S. et al.  Protracted Core Formation and Impact Disruptions Shaped the Earliest Outer Solar System Planetesimals [#1304]
Superchondritic HSE/Ni ratios in CC iron cores result from solid-liquid metal partitioning during protracted core formation, not CAI accretion. Early planetesimal disruptions shaped outer solar system bodies.
Wilbur Z. E. et al.  An Exogeneous, Eucrite-Like Pyroxene Grain Observed in a Breccia from Bennu [#1475]
We observed an anomalous pyroxene grain in Bennu sample OREX-800150-12. Textural, chemical, and isotopic evidence points to an exogeneous, eucrite-like origin of the pyroxene grain. We will discuss the timing of incorporation of this grain to Bennu.
Hammontree A. K. et al.  Type B, or Not Type B, Plag is the Question: A Petrologic Analysis of Diogenite Meteorites [#1503]
This study aims to determine if four orthopyroxenitic diogenites could be reclassified as Yamato Type B diogenites. Yamato Type B diogenites are rare and addition of further samples would aid in the understanding of igneous processes on Vesta.
Burton-Denny G. R. et al.  Testing Early Vestan Physical Evolution Models by Modeling Rare Earth Element Distributions of Crustal Products [#1872]
We model potential physical evolutions of Vesta as melting of a primordial interior, crystallization of a magma ocean, and melting of magma ocean cumulates, and evaluate the consistency of the results with REE abundances in Eucrites and Diogenites.
Day J. M. D. et al.  An Early Solar System Population of Fully Differentiated Planetesimals with Evolved Crusts [#1047]
Evolved asteroidal crusts formed both prior to and after core formation were important for 26-Al, volatile and incompatible trace element inventories as feedstocks to larger planetary bodies.

Special Session: Extended Missions: Teaching Old Spacecraft New Tricks

Eubanks T. M. et al.  An Interstellar Target of Opportunity: Spacecraft Observations of the Interstellar Object 3I/ATLAS [#1786]
The interstellar object 3I/ATLAS, discovered July 1, 2025, is possibly a relic from billions of years before the solar system formed. Here, we describe initial results from the 24-spacecraft campaign mounted to observe this object.
Koeppel A. H.D. et al.  Assessing Scientific Productivity of NASA’S Space Missions by Cost [#1606]
We analyzed publications from 90 NASA science missions since 1994 to determine the scientific efficacy of low-cost missions. We find that mid-tier missions ($250-750M) offer the best “time-to-science” and scientific productivity per dollar.

Thursday, March 19, 2026

Astrobiology: Solving the Mysteries of Life in the Universe

Cooper G. et al.  Interstellar Deuterated Water and Radiation in the Formation of Enantiomer Excesses in Meteoritic Organic Compounds [#1831]
Deuterated water on interstellar grains may have catalyzed the formation of enantiomer (mirror-image) excesses in meteoritic sugar derivatives.
Ulibarri Z. et al.  Hypervelocity Impact Ionization of Amino-Acid-Laden Dust: First Direct Measurements and Implications for Instrument Capabilities and Prebiotic Chemistry [#1891]
Here we present the first hypervelocity acceleration and impact ionization mass spectral study of dust grains containing amino acids. This is key for understanding micrometeorite gardening of prebiotic chemistry and flyby spacecraft instrumentation.
Rodriguez L. E. et al.  The Astrobiology Spectral Database v1.0: A Repository for Abiotic Organic Spectra [#1782]
The Astrobiology Spectral Database is a repository for mass spectrometry and NMR datasets of abiotic organic standards, reactions, and astromaterial extracts. Updates from a community survey, 2025 workshop, and website development will be presented.
Osborne S. D. et al.  Brines Allow for Bending of Prokaryotic Ubiquitin Without a Substrate [#1620]
Here, we study the habitability of chaotropic/kosmotropic brines. The salt species present in the brine affects the sphere of hydration and hydrogen bonds of proteins in solution. This allows for folding or unfolding of the ancient protein (PUP).
Morrison C. et al.  In-Situ Radioisotope Sterilization For Cost-Effective Forward and Backward Planetary Protection for Planetary Science and Sample Return Missions [#1821]
Radioisotope-based in-situ sterilization is a novel mission element that can cost-effectively address planetary protection. This presentation overviews maturation efforts under a NASA Phase I SBIR and solicits feedback from the science community.

Presolar Materials from Meteorites and Missions

Liu N. et al.  New NanoSIMS Multielement Isotope Data Reveal CO Novae as Key Sources of 13C-Rich Presolar SiC Grains [#1016]
Our new NanoSIMS multielement isotope data, together with new CO and ONe nova models, indicate that 13C-rich presolar SiC grains lacking neutron-capture isotopic signatures most likely originated in CO novae of low- to intermediate-mass.
Nguyen A. N. et al.  An Unusual Large Supernova Graphite with Abundant 18O-Rich Subgrains from an Asteroid Ryugu Sample [#1319]
We report the isotopic and mineralogical characterization of a large presolar graphite grain found in an asteroid Ryugu sample.

Space Weathering on Asteroids and the Moon

Kurosawa K. et al.  A Formation Mechanism of Sub-Micron Craters on a Ryugu Particle [#1399]
The origin of sub-micron craters found on a Ryugu particles is discussed. We investigated the size effects on the thermodynamics of hypervelocity impacts. “An expanding spray of melt droplets” may be launched from a micro meter-sized parent crater.
Hiroi T. et al.  Comparison of 2.7-Micron Absorption Bands of Asteroid Ryugu and Bennu Samples, Asteroids Polana and Pallas, and Fresh CI1 Chondrite Oued Chebeika 002 [#1076]
The 2.7-um hydroxy absorption band characteristics indicate that asteroids Bennu and Polana are space-weathered CI1-chondrite parent bodies while the JWST spectrum of asteroid Pallas may not be interpreted in the same way due to its size and albedo.
David G. et al.  Mid-Infrared Spectral Signatures of Laser-Irradiated Phyllosilicates and Basalt: Implications for Space Weathering on Airless Bodies [#1484]
This study explores how micrometeorite impacts alter the mid-infrared spectral properties of airless body surfaces, using laser experiments on phyllosilicates and basalt to better interpret remote sensing data and understand surface evolution.

Impacts: The Final Frontier — From Planet Formation to Surface Modification

Kikuchi S. et al.  Particle Dynamics at Ryugu Driven by the Hayabusa2 Impactor and Thruster Plumes [#1393]
Hayabusa2 operations at Ryugu caused major particle ejections during the SCI impact and touchdown thruster firings. We reconstruct their 3D trajectories from in-situ images to constrain surface mechanical properties and resurfacing processes.
Cashion M. D. et al.
Development of the IVANS Model for Chondrule Formation: Modeling Vaporization of Ice-Rock Mixtures [#1277]
We use iSALE-2D to compare methods of treating rock-ice mixtures with experimental data. Allowing the two materials to evolve according to their respective EOS best replicates partial vaporization of water ice during planetesimal collisions.

In-Person Poster Session 2: Impacts: The Final Frontier — From Planet Formation to Surface Modification

Solana P. et al.
Hydrocode Simulations of the Lockne Crater Using Rubble-Pile Asteroids with Variable Internal Structure [#1654]
This study uses hydrocode simulations with the iSALE-2D shock physics code to investigate how rubble-pile asteroid internal structure and aspect ratio control shock propagation, excavation dynamics, and crater morphology at the Lockne marine impact.
Nishio T. et al.
Influence of Target’s Gravity on Ejecta Dynamics and Change in Asteroid Velocity [#1382]
The target’s gravity can affect momentum transfer efficiency at impact, but its influence remains unclear. We use impact simulations to analyze the velocity distribution of the ejecta and investigate the influence of the target’s gravity.
Bruski S. M. et al.
Constraining Martian Atmospheric Effects on Binary Asteroid Systems Using Doublet Crater Morphologies [#1951]
Doublet Crater research has been linked to binary asteroids for many years; this study will estimate the effects of atmospheric interactions on binary asteroid systems just before impact on the planet Mars.

In-Person Poster Session 2: Space Weathering on Asteroids and the Moon