Silver And Earth's Volatile Origins
Thursday, May 13, 2010 - 14:11
in Astronomy & Space
By analyzing tiny variations in the isotopic composition of silver in meteorites and Earth rocks, scientists are putting together a timetable of how our planet was assembled 4.5 billion years ago. The new study, published in Science, indicates that water and other key volatiles may have been present in at least some of Earth's original building blocks, rather than acquired later from comets, as some scientists have suggested. Compared to the Solar System as a whole, Earth is depleted in volatile elements, such as hydrogen, carbon, and nitrogen, which likely never condensed on planets formed in the inner, hotter, part of the Solar System. Earth is also depleted in moderately volatile elements, such as silver. read more