Ming‐Chang Liu
A5015438916- Astro and Planetary Science
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Geological and Geochemical Analysis
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Ion-surface interactions and analysis
- High-pressure geophysics and materials
- Paleontology and Stratigraphy of Fossils
- Mesoporous Materials and Catalysis
- Geochemistry and Elemental Analysis
- Nuclear Physics and Applications
- Laser-induced spectroscopy and plasma
- Cell Image Analysis Techniques
- Polyoxometalates: Synthesis and Applications
- Diamond and Carbon-based Materials Research
- Advanced Neural Network Applications
- Analytical chemistry methods development
- earthquake and tectonic studies
- Zeolite Catalysis and Synthesis
- Domain Adaptation and Few-Shot Learning
- Digital Imaging for Blood Diseases
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
Planetary Science Institute
2016-2024
University of California, Los Angeles
2009-2024
Lawrence Livermore National Laboratory
2006-2024
National Aeronautics and Space Administration
2024
Osaka Health Science University
2024
Osaka University
2024
Johnson Space Center
2024
Sony Corporation (United States)
2016-2023
Westwood College
2022
NASA Planetary Science
2022
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. preliminary examination these samples shows that the nonvolatile portion is an unequilibrated assortment materials have both presolar solar system origin. contains abundance silicate grains are much larger than predictions interstellar grain models, many high-temperature minerals appear formed in inner regions nebula. Their presence a proves formation included...
Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme anomalies rare, indicating that the is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen neon isotope ratios suggest indigenous organic matter highly volatile materials were successfully collected. Except for single 17 O-enriched circumstellar stardust grain, silicate oxide minerals have consistent with solar system origin. One...
Carbonaceous meteorites are thought to be fragments of C-type (carbonaceous) asteroids. Samples the asteroid (162173) Ryugu were retrieved by Hayabusa2 spacecraft. We measured mineralogy and bulk chemical isotopic compositions samples. The samples mainly composed materials similar those carbonaceous chondrite meteorites, particularly CI (Ivuna-type) group. consist predominantly minerals formed in aqueous fluid on a parent planetesimal. primary altered fluids at temperature 37° ± 10°C, about...
Abstract Volatile and organic-rich C-type asteroids may have been one of the main sources Earth’s water. Our best insight into their chemistry is currently provided by carbonaceous chondritic meteorites, but meteorite record biased: only strongest types survive atmospheric entry are then modified interaction with terrestrial environment. Here we present results a detailed bulk microanalytical study pristine Ryugu particles, brought to Earth Hayabusa2 spacecraft. particles display close...
Little is known about the origin of spectral diversity asteroids and what it says conditions in protoplanetary disk. Here, we show that samples returned from Cb-type asteroid Ryugu have Fe isotopic anomalies indistinguishable Ivuna-type (CI) chondrites, which are distinct all other carbonaceous chondrites. Iron isotopes, therefore, demonstrate CI chondrites formed a reservoir was different source regions asteroids. Growth migration giant planets destabilized nearby planetesimals ejected some...
The extraterrestrial materials returned from asteroid (162173) Ryugu consist predominantly of low-temperature aqueously formed secondary minerals and are chemically mineralogically similar to CI (Ivuna-type) carbonaceous chondrites. Here, we show that high-temperature anhydrous primary in chondrites exhibit a bimodal distribution oxygen isotopic compositions: 16O-rich (associated with refractory inclusions) 16O-poor chondrules). Both the probably inner solar protoplanetary disk were...
Significance The crust or its chemically weathered derivatives likely served as a substrate for the origin of life, which could have occurred by 4.1 Ga. Yet no known bona fide terrestrial rocks from this time remain. Studies thus turned to geochemical signatures within detrital zircons time. While do not directly record low-temperature weathering processes, they inherit isotopic information upon recycling and remelting sediment. We developed method fingerprint identity material involved in...
Convolutional Neural Networks (CNN) have demonstrated its successful applications in computer vision, speech recognition, and natural language processing. For object CNNs might be limited by strict label requirement an implicit assumption that images are supposed to target-object-dominated for optimal solutions. However, the labeling procedure, necessitating laying out locations of target objects, is very tedious, making high-quality large-scale dataset prohibitively expensive. Data...
Abstract The delivery of water to the inner Solar System, including Earth, is still a debated topic. A preferential role for hydrated asteroids in this process supported by isotopic measurements. Carbonaceous chondrite (CC) meteorites represent our main source information about these volatile-rich asteroids. However, destruction weaker materials during atmospheric entry creates bias CC data. return surface from C-type asteroid 162173 Ryugu Hayabusa2 spacecraft provides unique opportunity...
Preliminary analyses of asteroid Ryugu samples show kinship to aqueously altered CI (Ivuna-type) chondrites, suggesting similar origins. We report identification C-rich, particularly primitive clasts in that contain preserved presolar silicate grains and exceptional abundances SiC isotopically anomalous organic matter. The high abundance (104 ppm) indicates the clast escaped extensive alteration. 5 10 times higher (~235 ppm), N-rich matter, organics with N isotopic anomalies (1.2%), C (0.2%)...
Studies of material returned from Cb asteroid Ryugu have revealed considerable mineralogical and chemical heterogeneity, stemming primarily brecciation aqueous alteration. Isotopic anomalies could also been affected by delivery exogenous clasts mobilization soluble elements. Here, we show that isotopic for mildly Cr are highly variable in CI chondrites, whereas those Ti relatively uniform. This variation isotope ratios is most likely due to physicochemical fractionation between 54Cr-rich...
The isotopic compositions of samples returned from Cb-type asteroid Ryugu and Ivuna-type (CI) chondrites are distinct other carbonaceous chondrites, which has led to the suggestion that Ryugu/CI formed in a different region accretion disk, possibly around orbits Uranus Neptune. We show that, like for Fe, CI also have indistinguishable Ni isotope anomalies, differ those chondrites. propose this unique Fe composition reflects efficiencies small FeNi metal grains among chondrite parent bodies....
Abstract We have conducted a NanoSIMS-based search for presolar material in samples recently returned from C-type asteroid Ryugu as part of JAXA's Hayabusa2 mission. report the detection all major grain types with O- and C-anomalous isotopic compositions typically identified carbonaceous chondrite meteorites: 1 silicate, oxide, O-anomalous supernova ambiguous phase, 38 SiC, 16 grains. At least two grains are graphites, whereas several moderate C anomalies probably organics. The silicate was...
Abstract Micrometeorites, a possible major source of Earth’s water, are thought to form from explosive dispersal hydrated chondritic materials during impact events on their parental asteroids. However, this provenance and formation mechanism have yet be directly confirmed using asteroid returned samples. Here, we report evidence mild shock metamorphism in the surface particles Ryugu based electron microscopy. All dominated by phyllosilicates but lack dehydration textures, which indicative...
Abstract The great oxidation event (GOE), ~2.4 billion years ago, caused fundamental changes to the chemistry of Earth's surface environments. However, effect these on biosphere is unknown, due a worldwide lack well‐preserved fossils from this time. Here, we investigate exceptionally preserved, large spherical aggregate (SA) microfossils permineralised in chert c. 2.4 Ga Turee Creek Group Western Australia. Field and petrographic observations, Raman spectroscopic mapping, situ carbon...