These incredible images from our Mars Express probe shows the dried-up remains of what was once the largest lake on the Red Planet – dwarfing anything we have on Earth!
Nicknamed “Lake Eridania,” this vast body of water stretched for over a million square kilometers. While the water’s gone now, Mars Express is helping scientists piece together the Martian climate and search for signs of past life.
Alongside water, there are clear signs of volcanism at play in and around the area.
Two long cracks run vertically down through the image, cross-cutting both the aforementioned lakebed and the smoother ground to the left. These are known as the Sirenum Fossae faults, and formed as Mars’s Tharsis region – home to the largest volcanoes in the Solar System – rose up and put immense stress on Mars’s crust.
Volcanic stress is also to blame for the many wrinkle ridges found here. These appear as wriggly lines weaving across the frame horizontally. Wrinkle ridges are common on volcanic plains, forming as new lava sheets are compressed while still soft and elastic, causing them to buckle and deform.
The impact craters here, created as space rocks collided with Mars, are also fascinating. The large central crater shows signs of flowing material and carved-out valleys on its southern (left) rim, indicating that water may have existed here even after Lake Eridania disappeared.
The smaller crater to its south (left) has been eaten away by small gullies on its northern (right) flank, while the rightmost part of the image displays a number of ancient craters that are barely recognisable as craters, having been heavily broken down and eroded away over time.
