Noble gas study of HEDs Meteorites
The Talk focuses on noble gas components in Howardites, Eucrites, and Diogenites (HED) meteorites, which originate from the asteroid Vesta. Noble gases serve as tracers for atmospheric contamination and differentiation, providing insights into the planetary histories of Vesta and other celestial bodies. The investigation covers trapped neon, which reveals the absence of solar wind components, and Argon, Krypton, and Xenon. These gases are analyzed using elemental ratios to distinguish between crustal and mantle components of Vesta. The research also indicates cosmic ray exposure ages, suggesting significant ejection events occurred around 22 million years ago. Comparisons with Earth and chondrites highlight diverse degassing histories among differentiated objects. The study's primary objectives are to understand the trapped components and cosmic ray exposure ages in parent bodies and to shape our understanding of volatile evolution in Vesta. Differentiated celestial bodies like Mercury, Venus, Earth, Mars, and Vesta have metallic cores and silicate shells, with chondrites representing their building blocks. HED meteorites provide valuable insights due to their known parent body, Vesta. The study aims to comprehend the isotopic systematics of noble gases in Vesta, Earth, and Mars through differentiated mantle-derived materials. Elemental ratios in noble gases help differentiate components in Eucrites and Diogenites, offering insights into Vesta's crust and mantle. Eucrites represent crustal components, while Diogenites reflect interior components. The study gains insights into Vesta's ejection history through cosmic ray exposure ages, particularly highlighting a major event around 22 million years ago. Comparative analysis of noble gases in Eucrites, Diogenites, MORB (Mid-Ocean Ridge Basalts), OIB (Ocean Island Basalts), and Martian samples reveals distinct degassing histories among Vesta, Mars, and Earth. The research provides a comprehensive understanding of noble gas isotopic compositions in these celestial bodies.