Researchers developed a device that uses florescence from oil (left) to detect its presence and identify the type of oil. The small and simple device incorporates inexpensive electronic components (right). Credit: Oscar Sampedro, Universidade de Vigo.

Jun Wang (sitting), Christopher Eng (standing), Jiajun Wang (left, laptop screen), and Liguang Wang of Brookhaven National Laboratory used transmission x-ray microscopy combined with spectroscopy to produce the colored maps shown on the large screen. These maps reveal the structural expansion (and the resulting cracks/fractures) and chemical composition changes that occur as sodium ions (Fe, green) are added to and removed from iron sulfide (FeS, red) during the battery’s first discharge/charge cycle. The pristine iron sulfide (box in upper left) does not return to its original state after this cycle, as some sodium ions remain trapped in the core (box in lower right). As a result, there is an initial loss in battery capacity. Credit: Brookhaven National Laboratory

1. The dark, narrow, 100-meter-long streaks flowing downhill within the Hale Crater on Mars in this rendering are inferred to have been formed by flowing water in this false-color image that was draped on a digital terrain model. Credit: NASA JPL, University of Arizona
2. An impact crater on Mars, named Melas Dorsa, and its surroundings show a rich geologic history. The image was created by the European Space Agency’s Mars Express. Studies of the transformation of a synthetic version of a mineral known as whitlockite suggest that Mars had a more water-rich past than previously thought. Credit: G. Neukum/ESA,DLR, FU Berlin
3. Naturally formed crystals of the mineral whitlockite, which is rare on Earth, are visible in this sample on display at Canada’s Royal Ontario Museum...

This artist’s concept shows what each of the TRAPPIST-1 planets may look like, based on available data about their sizes, masses and orbital distances. Credit: NASA/JPL-Caltech