Baby Spider: Growth of a Martian Trough Network

This image from NASA Mars Reconnaissance Orbiter shows the growth of a branching network of troughs carved by thawing carbon dioxide over the span of three Martian years. This process is believed to also form larger radially patterned channel features known as Martian "spiders."

The image is one of three taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter and included in a report on the first detection of such troughs persisting and growing, from one Mars year to the next.

An animation is available at http://photojournal.jpl.nasa.gov/catalog/PIA21257