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This image comparison demonstrates NuSTAR's improved ability to focus high-energy X-ray light into sharp images. The image on the left, taken by the European Space Agency's INTEGRAL satellite, shows high-energy X-rays from galaxies beyond our own. The light is "unresolved," meaning that individual objects creating the light -- in particular, the active supermassive black holes -- cannot be distinguished.
( Photo / ESA/NASA/JPL-Caltech)