The high-resolution stereo camera (HRSC) on ESA’s Mars Express orbiter imagined a fascinating landscape near the major Valles Marineris canyon system on the red planet.
Valles Marineris is a vast canyon system that runs along the Martian equator just east of the Tharsis region.
It is 4,000 km (2,500 miles) long and reaches depths of up to 7 km (4 miles) – about 10 times longer and 5 times deeper than Arizona’s Grand Canyon.
It includes countless rifts, channels, streams, fractures and signs of flowing material (such as water, ice, lava or debris).
Valles Marineris is an unmissable scar on the face of Mars and is believed to have formed as the planet’s crust was stretched by nearby volcanic activity, causing it to break and open before collapsing into the deep gutters. which we see today.
These gutters have been further shaped and eroded by water flows, landslides and other erosive processes, with spacecraft including Mars Express spying signs that water has existed in parts of Valles Marineris in the relatively recent past.
The new image of the Mars Express HRSC instrument shows “chaotic terrain” in the Pyrrhae Regio – a region south of Eos Chasma, an eastern branch of the Valles Marineris system.
To the left of the frame can be seen a scattering of impact craters, formed as the bodies received from space collided with the surface of Mars.
The floor of the largest and highest basin stretches for about 40 km and contains several fractures and markings that formed immediately after the crater itself.
It is believed that the hot, molten rock was thrown during the crater-forming collision, after which it cooled and settled to form the scar-like features visible here.
Towards the middle of the frame, the surface is relatively smooth and without features – however, two wide channels have made their way through the landscape and can be seen as meandering indentations, branched into the surrounding terrain.
The valleys are attached to the right end of the real star of the image: a patch of sunken, uneven, scarred ground, known as chaotic terrain.
Chaotic terrain, as the name suggests, looks uneven and mixed and is thought to form as ice and surface sediments begin to melt and change.
This layer of change causes the surface above to collapse – a collapse that can happen quickly and catastrophically as the water drains rapidly through the Martian rule.
Ice can be triggered by melting by events such as volcanic lava flows, surface magmatism, the impact of large meteorites or climate change.
In the chaotic terrain seen here, the ice melted, the resulting water leaked, and a series of disparate broken blocks were left standing in the now empty cavities.
Remarkably, the floors of these cavities are about 4 km (2.5 miles) below the flatter ground, near the craters on the left.