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Oil spill in oceans is identified as a key environmental issue resulting in water contamination and major harm to marine life. These spills in ice-infested waters can be even more catastrophic as the process of ice melting is non-trivial and adds an additional complexity in determining the extent of the oil spread from the initial spill zone. The prediction of the impact and extent of the spill assists in employing the required clean-up countermeasures. A validated numerical model that simulates the oil spread is reported in this study, where the spread of an oil layer in ice is analyzed. Experiments in literature have shown that for solar radiation flux higher than 0.5 kW/m2, the oil temperatures can be around 5 - 6 ºC even if the ambient is at sub-zero temperature. This surface heating is simulated in the numerical model to study the effect of in-depth heating of oil on the ice melting to further analyze the spreading of oil in the melt zone. 

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed seventeen Ryugu samples measuring 1-8 mm. CO 2 -bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu’s parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and Ca, Al-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed by aqueous alteration reactions at low temperature, high pH, and water/rock ratios < 1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate Ryugu’s parent body formed ~ 2 million years after the beginning of Solar System formation.