At first, figuring out how pebble-sized rocks organize themselves in evenly-spaced patterns in sand seemed simple and even intuitive. But once Andrew Leier, an assistant geoscience professor at the U of C, started observing, he discovered that the most commonly held notions did not apply.

High-resolution images of Martian volcanoes have revealed areas that show signs of recent lava flow.

A plateau on Mars known as Home Plate shows evidence of long-past explosive volcanic activity, say scientists on NASA's Mars Exploration Rover mission. And data collected during the rover Spirit's initial pass across the 90-meter (295 feet) wide plateau also supports earlier findings indicating that water once existed at or beneath the planet's surface.