The Chelyabinsk asteroid impact is the second largest asteroid airburst in our recorded history. To prepare for a potential threat from asteroid impacts, it is important to understand the nature and formational history of Near-Earth Objects (NEOs) like Chelyabinsk asteroid. In orbital evolution of an asteroid, collision with other asteroids is a key process. Here, we show the existence of a high-pressure mineral jadeite in shock-melt veins of Chelyabinsk meteorite. Based on the mineral assemblage and calculated solidification time of the shock-melt veins, the equilibrium shock pressure and its duration were estimated to be at least 3–12 GPa and longer than 70 ms, respectively. This suggests that an impactor larger than 0.15–0.19 km in diameter collided with the Chelyabinsk parent body at a speed of at least 0.4–1.5 km/s. This impact might have separated the Chelyabinsk asteroid from its parent body and delivered it to the Earth.
High-temperature Raman spectroscopy was applied to study model silicate melts in the M2O-SiO2 system, where M = K, Na, or Li. Structural units of the melts and equilibrium constants of reactions between them are determined. Thermodynamic calculations were conducted for the dependence of the Qn distribution on the composition and temperature, and the results of thermodynamic simulations were demonstrated to be consistent with the experimental results.