All posts tagged: volatile elements

Ancient impact with Theia may have brought water and life to Earth

Ancient impact with Theia may have brought water and life to Earth

Published by Jenni Sidey

Earth’s story may have hardened into place almost as soon as the Solar System began. That is the striking claim in new research tracing when the young planet locked in the chemical makeup that still defines it. According to the analysis, proto-Earth appears to have reached that point no later than about 3 million years after the first solids formed in the Solar System, an eye blink in planetary terms. Yet that early world was probably nothing like the one you know now. It was likely dry, depleted in volatile elements, and missing much of what life would later need. The work points to a two-stage history. First came a fast chemical settling of the material that built Earth’s main body. Much later, a giant impact may have supplied the water and other volatile ingredients that made the planet habitable. The result shifts the timing. It also changes the mood of Earth’s origin story. ε53Cr evolution of CCs and their intersection ages (model ages) with the bulk Solar System. (CREDIT: Science Advances) Instead of a …

Planetary scientists reveal where Earth’s water and building blocks came from

Planetary scientists reveal where Earth’s water and building blocks came from

Published by Jenni Sidey

For years, planetary scientists have argued that some of the material that built Earth must have drifted in from beyond Jupiter, carrying water and other volatile ingredients with it. Estimates often put that outer Solar System share somewhere between 6 percent and 40 percent. A new analysis led by ETH Zurich researchers Paolo Sossi and Dan Bower takes a very different view. After comparing Earth’s isotopic makeup with that of meteorites, Mars and the asteroid Vesta, they argue that Earth formed almost entirely from material already present in the inner Solar System. That does not mean the question is settled. Sossi himself says the debate over Earth’s building blocks is “far from over.” But the new study, published in Nature Astronomy, sharply narrows the room for one popular idea, that large amounts of outer Solar System matter crossed Jupiter’s orbit and became part of the growing Earth. “We were truly astonished to find that the Earth is composed entirely of material from the inner Solar System distinct from any combination of existing meteorites,” Bower said. …