Clouds that are probably composed of ice crystals and possibly supercooled water droplets were caught in images by NASA’s Opportunity rover.

NASA/JPL/Texas A&M/Cornell

As Curiosity continues its epic drive to Aeolis Mons — the 3.5 mile-high mountain in the center of Gale Crater dubbed “Mount Sharp” — it has taken some time to turn its cameras skyward. In a recent series of images sent back from the Red Planet, the six-wheeled rover tracked a formation of clouds drift overhead, blown by high altitude winds.

So far, the rover has been focusing most of its attention downwards, drilling into rock and sampling dust in its on-board chemistry laboratory. The key aim of the car-sized robot is to gain an understanding of ’ past and present habitable potential. 
Basically it wants to help us answer the question: Could Mars have ever supported microbial life?

From the evidence pieced together after two years of roving inside Gale Crater, the answer is a resounding “yes.” Curiosity has discovered proof that large bodies of water used to persist on the Red Planet’s surface and it has chemically deciphered samples to find minerals that could only have been formed in the presence of liquid water. Tests of Martian regolith have also revealed that the planet has substantial quantities of water near the surface.

The presence of water is exciting, but evidence of ancient pooling liquid water on Mars is very exciting. Liquid water supports the evolution of life as we know it, might Mars have also supported life? Although Curiosity isn’t designed to look for direct evidence of life, it is providing a detailed picture of Mars’ life-giving potential.

Now, by looking at the skies, Curiosity has identified clouds that are most likely formed through the accumulation of water ice crystals or supercooled water droplets. This adds another dimension to our understanding of Mars’ current climate and its ancient .

“Clouds are part of the planet’s climate system,” Robert M. Haberle, Planetary Scientist at NASA Ames and a team member for the Rover Environmental Monitoring Station (REMS), told Astrobiology Magazine. “Their behavior tells us about winds and temperatures.”

“Some studies suggest that clouds in the past may have significantly warmed the planet through a greenhouse effect. A warmer environment is more conducive to life,” he said.

Mars is abundant in aeolian formations, features that have been shaped by Mars’ winds — such as dunefields. Through observations of drifting clouds, scientists can better understand weather patterns and global climate dynamics. These studies, in turn, complement Curiosity’s geology work where it continues to piece together Mars’ climatic history from clues locked in Mars rock.