seifertite tagged posts

A model of the crystal structure of cristobalite X-I, which had never before been discovered in other materials. This high-pressure phase of cristobalite is made up of two layers (green and blue), each composed of Si?O. Credit: Leonid Dubrovinsky

A research group at the University of Bayreuth has found a long-sought explanation for the apparent contradictions implicit in the composition of lunar and Martian meteorites. In cooperation with the German Electron Synchrotron (DESY) in Hamburg, the European Synchrotron Radiation Facility (ESRF) in Grenoble and research partners in Lyon and Vienna, the Bayreuth scientists led by Prof. Dubrovinsky were able to demonstrate how meteorites could contain within narrow spaces minerals whose formation conditions are quite different.

When asteroids or co...

1. Cristobalite crystals from Harvard Mineralogical Museum, found at Ellora caves in India. Credit: RRUFF Project / University of Arizona
2. A fresh impact crater on Mars, as imaged by the HiRISE camera on board NASA’s Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona

X-ray analysis reveals unexpected behaviour of silica minerals. With high-pressure experiments at DESY’s X-ray light source PETRA III and other facilities, a research team around Leonid Dubrovinsky from the University of Bayreuth has solved a long standing riddle in the analysis of meteorites from Moon and Mars. The study, published in the journal Nature Communications, can explain why different versions of silica can coexist in meteorites, although they normally require vastly different conditions to form...