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I AM on the lookout for clouds this month. I won’t be searching here on Earth, though – that would be too easy. Instead, I am helping researchers spot clouds in the skies above our neighbouring planet Mars. You can join in this effort too, from anywhere in the world, by participating in the project.

This initiative is calling for volunteers to find clouds high up in the Martian atmosphere by searching through years of data from NASA’s Mars Reconnaissance Orbiter. This spacecraft observes the Martian horizon with an instrument called the Mars Climate Sounder, which detects infrared light emitted from the planet’s surface. Clouds in the upper atmosphere reflect some of this light, creating arched peaks in graphs of the data (pictured).

at NASA’s Jet Propulsion Laboratory in California and his colleagues want to use this information to create a map of the clouds on Mars, including records of how they move and change over time, so that they can learn more about the Red Planet’s climate. But the spacecraft has already gathered eight Martian years’ – 16 Earth years’ – worth of data, which is more than the researchers can analyse on their own.

As a volunteer, you will flick through graphs of the data online and mark any arch-shaped peaks, which indicate clouds. There is a tutorial available on the project’s web page to get you started.

Volunteers have inspected hundreds of thousands of graphs since the project launched in June, finding an average of three clouds in each one. As well as helping researchers like Slipski develop a clearer picture of climate patterns across Mars, their work is also being used to train an algorithm that will automatically recognise and label clouds in future data from the NASA mission.

Mars is much colder than Earth, and so are its clouds, which are made of both water ice and carbon dioxide ice – also called dry ice. Slipski and his colleagues hope that the data from Cloudspotting on Mars will let them investigate why the planet’s atmosphere gets cold enough for carbon dioxide to freeze, and that it will inform them about how clouds on Mars change between day and night, as well as across seasons and years.

“Ultimately, we want to know what processes are involved in forming these clouds,” says Slipski. “When do clouds form? And where do they form?”

Clouds are a huge source of uncertainty in climate models on Earth, let alone on Mars, says Slipski. Mapping cloud patterns could help modellers to improve predictions about how the climate on Mars is likely to change in the future, and about what it might have been like in the distant past.

Layal Liverpool is a science journalist based in Berlin. She believes everyone can be a scientist, including you.@layallivs

Visit and search for “Cloudspotting on Mars” to contribute to this other-worldly research.