Night LabyrinthBright material litters the floor of a trough in Noctis Labyrinthus, a maze-like region of deep valleys near one of Mars's volcanic plains.The recently released image was snapped by NASA's Mars Reconnaissance Orbiter. Other data from the spacecraft suggest that the material is hydrated—that is, it contains water in its atomic structure.Scientists think the hydrated material could have formed long ago, either from subsurface water upwelling in the trough or from surface ice melting from the heat of nearby volcanic activity.
Image courtesy U. Arizona/NASA

Space Pictures This Week: Monkey Head, Cloud Hole, More

A simian nebula, a galactic illusion, and a hole in the sky feature among our editors' picks for this week's best space pictures.

June 17, 2012

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