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There is a long-standing debate regarding the origin of the terrestrial planets water as well as the hydrated C-type asteroids. Here we show that the inner Solar Systems water is a simple byproduct of the giant planets formation. Giant planet cores accrete gas slowly until the conditions are met for a rapid phase of runaway growth. As a gas giants mass rapidly increases, the orbits of nearby planetesimals are destabilized and gravitationally scattered in all directions. Under the action of aerodynamic gas drag, a fraction of scattered planetesimals are deposited onto stable orbits interior to Jupiters. This process is effective in populating the outer main belt with C-type asteroids that originated from a broad (5-20 AU-wide) region of the disk. As the disk starts to dissipate, scattered planetesimals reach sufficiently eccentric orbits to cross the terrestrial planet region and deliver water to the growing Earth. This mechanism does not depend strongly on the giant planets orbital migration history and is generic: whenever a giant planet forms it invariably pollutes its inner planetary system with water-rich bodies.
The ungrouped iron meteorite Nedagolla is the first meteorite with bulk Mo, Ru, and Ni isotopic compositions that are intermediate between those of the non-carbonaceous (NC) and carbonaceous (CC) meteorite reservoirs. The Hf-W chronology of Nedagolla
We compare line emission calculated from theoretical disk models with optical to sub-millimeter wavelength observational data of the gas disk surrounding TW Hya and infer the spatial distribution of mass in the gas disk. The model disk that best matc
Over the last eight years, the Visual and Infrared Mapping Spectrometer (VIMS) aboard the Cassini orbiter has returned hyperspectral images in the 0.35-5.1 micron range of the icy satellites and rings of Saturn. These very different objects show sign
Formation and evolution of water in the Solar System and the origin of water on Earth constitute one of the most interesting questions in astronomy. The prevailing hypothesis for the origin of water on Earth is by delivery through water-rich small So
Geochemical and astronomical evidence demonstrate that planet formation occurred in two spatially and temporally separated reservoirs. The origin of this dichotomy is unknown. We use numerical models to investigate how the evolution of the solar prot