When frozen carbon dioxide melted in summer, distinctive marks are revealed on the Martian landscape. These are known as “AraneidoForm field” because they resemble spiders when they are seen from space. Some of these spider reliefs measure more than a kilometer in diameter, and some have hundreds of legs. They are often in swarms. The above image was taken by the Mars recognition orbiter during the visualization of the southern hemisphere in 2009.
The processes that create these Araie formations are not entirely understood, although JPL is working to imitate the temperatures and pressures of March to recreate them.
The arrival of spring on Mars also brings strong winds, and it is believed that the characteristic spiral model of the northern polar cap of March has been created for many years by winds blowing from the center of the ceiling on its periphery. The spiral motif is due to the Coriolis effect, that is to say when the rotation of a planet folds the course of the winds.
The darkest parts of the spiral are actually deep canyons, which have been cut over a long period by spring winds. The Chasma Boreale, visible to the right of the center of the polar cap in the image, is particularly spectacular. It is as long as the Grand Canyon (approximately 450 kilometers) and up to 2 kilometers deep.
Strong spring winds also move sand dunes on the Martian surface, just as winds do in deserts on earth.
The white things you see in the image are the gel surrounding the raised dunes, which remain static while being frozen. When temperatures increase in spring and this ice melts, the dunes start to move due to the action of the wind.
“As we have seen, the beginning of spring on Mars is very active. You could even say “explosive”, says Diniega. “I imagine it would be very noisy, with things that crack and explode.”
This story originally appeared on Japan and has been translated from the Japanese.
