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Asteroid (596) Scheila was the first object for which the immediate aftermath of an inter-asteroidal collision was observed. In Dec. 2010, the 113 km-sized asteroid was impacted by a smaller asteroid of less than 100 m in diameter. The scale of the impactor was established by observations of fading ejecta plumes. Comparison of the light curves obtained before and after the impact allowed us to assess how much of Scheilas surface was altered. Cratering physics based on the impactor size suggests that the size of the affected area is larger than expected, (effective radii of 3.5 -- 10 km depending on the change in the albedo of the surface). Similar but more localized albedo changes have been observed on Vesta and the Martian moons, but are not understood. Empirical laws describing ejecta blankets however indicate that at distances between 3.5 -- 10 km from the crater, Scheilas surface would be covered by a thin layer 2 mm to 2 cm thick. This dusting, possibly mixed with bright impactor material may be enough to explain to observed brightness increase. Our results show that sub-critical impacts may play a significant role in processing the surfaces of asteroids. The large effect of small impacts on asteroidal light curves complicate shape modeling.
This work focuses on the study of the aqueous alteration process which acted in the main belt and produced hydrated minerals on the altered asteroids. The aqueous alteration is particularly important for unraveling the processes occurring during the
ESA and NASA maintain asteroid hazard lists that contain all known asteroids with a non zero chance of colliding with the Earth in the future. Some software tools exist that are, either, capable of calculating the impact points of those asteroids, or
We describe the first determination of thermal properties and size of the M-type asteroid (16) Psyche from interferometric observations obtained with the Mid-Infrared Interferometric Instrument (MIDI) of the Very Large Telescope Interferometer. We us
Photosynthesis is an ancient metabolic process that began on the early Earth, offering plentiful energy to organisms that utilize it, to the extent that they can achieve global significance. The potential exists for similar processes to operate on ha
Near-Earth asteroid 2014 AA entered the Earths atmosphere on 2014 January 2, only 21 hours after being discovered by the Catalina Sky Survey. In this paper we compute the trajectory of 2014 AA by combining the available optical astrometry, seven grou