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Core formation is the main differentiation event in the history of a planet. However, the chemical composition of planetary cores and the physicochemical conditions prevailing during core formation remain poorly understood. The asteroid 4-Vesta is the smal ...
Insoluble organic matter (IOM) in primitive carbonaceous meteorites has preserved its chemical composition and isotopic heterogeneity since the solar system formed similar to 4.567 billion years ago. We have identified the carrier moieties of isotopically ...
Based on early solar system abundances of short-lived radionuclides (SRs), such as Al-26 (T-1/2 = 0.74 Myr) and Fe-60 (T-1/2 1.5 Myr), it is often asserted that the Sun was born in a large stellar cluster, where a massive star contaminated the protoplaneta ...
Chondrules, which are the major constituent of chondritic meteorites, are believed to have formed during brief, localized, repetitive melting of dust ( probably caused by shock waves(1,2)) in the protoplanetary disk around the early Sun. The ages of primit ...
The Almahata Sitta MS-170 ureilite (a piece of a breccia originating from the asteroid, 2008 TC3) consists mainly of olivine, with many diamond and graphite grains existing between the olivine grains. The occurrences of the diamonds are unique; i.e., (i) s ...
Inner solar system bodies, including the Earth, Moon, and asteroids, are depleted in volatile elements relative to chondrites. Hypotheses for this volatile element depletion include condensation from the solar nebula and volatile loss during energetic impa ...
Energetic ions are found to be transported strongly from the core of MAST hybrid-like plasmas during long-lived mode (LLM)
magnetohydrodynamic activity. The resulting impact on the neutral beam ion deposition and concurrent current drive is
modelled usin ...
Asteroid 4 Vesta seems to be a major intact protoplanet, with a surface composition similar to that of the HED (howardite-eucrite-diogenite) meteorites(1-4). The southern hemisphere is dominated by a giant impact scar(5), but previous impact models(6-8) ha ...
Short-lived radionuclides were present in the solar protoplanetary disk in abundances much higher than in the ambient interstellar medium and require a last minute origin. Al-26 (T-1/2 = 0.73 Myr) and Ca-41 (T-1/2 = 0.1 Myr) abundances in the protoplanetar ...
The bulk of the comet 81P/Wild 2 ( hereafter Wild 2) samples returned to Earth by the Stardust spacecraft appear to be weakly constructed mixtures of nanometer-scale grains, with occasional much larger ( over 1 micrometer) ferromagnesian silicates, Fe-Ni s ...
