The Missing-Mantle Mystery - Earth's "Hidden Flux" Of Material Identified
Wednesday, July 17, 2013 - 11:20
in Astronomy & Space
The Earth has a violent history: About 4.5 billion years ago, a maelstrom of gas and dust circled in a massive disc around the sun, gathering in rocky clumps to form asteroids. These asteroids, gaining momentum, whirled around a fledgling solar system, repeatedly smashing into each other to create larger bodies of rubble — the largest of which eventually cooled to form the planets. Countless hypotheses, simulations and geologic observations support such a scenario, but there remains one lingering mystery: If the Earth arose from the collision of asteroids, its composition should resemble that of meteoroids, the small particles that break off from asteroids. read more