Excerpt:
Thin, blade-like walls, some as tall as a 16-story building, dominate a previously undocumented network of intersecting ridges on Mars, found in images from NASA’s Mars Reconnaissance Orbiter. The simplest explanation for these impressive ridges is that lava flowed into pre-existing fractures in the ground and later resisted erosion better than material around them. A new survey of polygon-forming ridges on Mars examines this network in the Medusae Fossae region straddling the planet’s equator and similar-looking networks in other regions of the Red Planet.
“Finding these ridges in the Medusae Fossae region set me on a quest to find all the types of polygonal ridges on Mars,” said Laura Kerber of NASA’s Jet Propulsion Laboratory, Pasadena, California, lead author of the survey report published this month in the journal Icarus.