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First X-ray View of Martian Soil
This graphic shows results of the first analysis of Martian soil by the Chemistry and Mineralogy (CheMin) experiment on NASA's Curiosity rover. The image reveals the presence of crystalline feldspar, pyroxenes and olivine mixed with some amorphous (non-crystalline) material. The soil sample, taken from a wind-blown deposit within Gale Crater, where the rover landed, is similar to volcanic soils in Hawaii. Curiosity scooped the soil on Oct. 15, 2012, the 69th sol, or Martian day, of operations. It was delivered to CheMin for X-ray diffraction analysis on October 17, 2012, the 71st sol. By directing an X-ray beam at a sample and recording how X-rays are scattered by the sample at an atomic level, the instrument can definitively identify and quantify minerals on Mars for the first time. Each mineral has a unique pattern of rings, or "fingerprint," revealing its presence. The colors in the graphic represent the intensity of the X-rays, with red being the most intense.

This picture shows a lab demonstration of the measurement chamber inside the Tunable Laser Spectrometer, an instrument that is part of the Sample Analysis at Mars investigation on NASA's Curiosity rover.

brain visual working memory circuit holds information in mind about what has just been seen. It represents the memory and distinguishes among objects via unique patterns of brain wave synchronization between neurons in the circuit. For example, two distant hubs in the circuit, one at the front of the brain (right circle) and the other at the rear side (left circle), showed varying amounts of synchrony in their brain waves, depending on what object a monkey was holding in memory. The coherence of synchronous activity between cells in these regions was plotted for different objects the monkey saw over several trials. The large area of red in the lowest graph indicates that the brain waves in the two regions were highly in-sync after seeing a particular object – indicating that they were highly involved in holding in short-term memory information about that object. The modest amount of red for the top graph indicates lesser involvement for another object. By contrast, lack of red in the middle graph shows that the two groups of neurons weren’t much involved in remembering a third object. So the memory of any particular object appears to be represented by its own unique mix of neurons oscillating in-sync.

The first x-ray crystallography view of Martian soil. Obtained by the Chemistry and Mineralogy (CheMin) experiment on NASA's Curiosity rover, these data reveal crystalline feldspar, pyroxenes and olivine mixed with some amorphous (non-crystalline) material. The soil sample is similar to volcanic soils in Hawaii.

AFM micrograph of 2D S-layers assembled on mica shows two different pathways to crystalization, one in which the domans are 2-3 nanometers taller (white circles). Height differences, measured along the dotted black line, were the result of kinetic trapping.

This shows the new all-carbon solar cell consists of a photoactive layer, which absorbs sunlight, sandwiched between two electrodes.

Before (left) and after (right) photos of the study site in Zhangye, China, show the magnitude of the May 2008 dust event.

Georgia Tech Professor Andrei Fedorov demonstrates the electron beam induced deposition (EBID) system used to create graphitic nanojoints to multi-walled carbon nanotubes.

Schematic to show the operation of AFM-IR