Cloudspotting on Mars
Do you want to help scientists look for clouds on Mars? Here’s your opportunity! Last week (June 28, 2022), NASA announced a new project called Cloudspotting on Mars. The agency is studying Mars’ wispy clouds to try to find out why the planet lost most of its once-thick atmosphere. Scientists want your help looking through images from the Mars Orbiter spacecraft to identify clouds in the Martian sky.
Although not as widespread as earthly clouds, clouds in Mars’ thin atmosphere are fairly common. Mars clouds tend to be wispy, like cirrus clouds on Earth. Mars orbiters, rovers and landers have all observed clouds in the Mars’ atmosphere (and produced some stunning photos.)
The Cloudspotting on Mars project is based on data obtained by NASA’s Mars Reconnaissance Orbiter (MRO). The spacecraft has been orbiting Mars since 2006, studying both the surface and atmosphere. Unlike our human eyes, which see in visible light, MRO’s Mars Climate Sounder instrument observes the atmosphere in infrared light.
How to cloudspot on Mars
Here’s where you come in: When clouds are present in the Martian atmosphere, they appear as narrow “arches” in the data. There’s 16 years of data so far to go through. And that’s a lot for a small team of scientists. NASA is asking for your help to search through that data and mark where the arches are found.
Your participation will help scientists map out where the clouds occur in Mars’ atmosphere. More info, plus a tutotial, here.
As Armin Kleinboehl, Mars Climate Sounder’s deputy principal investigator at JPL, said:
We now have over 16 years of data for us to search through, which is very valuable; it lets us see how temperatures and clouds change over different seasons and from year to year. But it’s a lot of data for a small team to look through.
Researcher Marek Slipski at JPL added:
We want to learn what triggers the formation of clouds – especially water ice clouds, which could teach us how high water vapor gets in the atmosphere – and during which seasons.
Cloudspotting on Mars … for science
Cloudspotting on Mars uses the citizen science platform Zooniverse. Scientists want to study clouds so they can better understand Mars’ atmosphere. There are still mysteries to solve. For example, why is Mars’ atmosphere only 1% as dense as Earth’s, when it used to be much thicker?
That is, in fact, one of the most important questions that is still not fully answered. How did Mars lose so much of its atmosphere?
And where did all the water go?
Scientists have posited various explanations. One theory suggests water molecules were lofted high into the atmosphere. If they rose high enough, then solar radiation might have broken the water molecules down into their separate constituents of hydrogen and oxygen. Hydrogen is a very light molecule, and could then simply drift out into space, escaping Mars altogether.
Abundant evidence shows that Mars once had lakes, rivers and maybe even an ocean. But when the atmosphere disappeared, for the most part, so did the liquid water. (Some of that water may also still be in Mars’ crust). There was no longer enough pressure or heat to sustain water on the planet’s surface. The fact that this water once existed, however, shows that the atmosphere must have been much thicker billions of years ago.
Different kinds of clouds
Many of the clouds on Mars are water ice clouds, just like on Earth. But Mars also has another type of cloud that our planet does not: carbon dioxide clouds. These clouds are able to form when the Martian atmosphere gets cold enough, which our atmosphere doesn’t. By studying these clouds as well, scientists can learn more about the middle atmosphere layer on Mars. This region extends from about 30 to 50 miles (50 to 80 km) in altitude.
Bottom line: Cloudspotting on Mars: Here’s how you can help NASA identify Mars’ wispy clouds, in order to try to find out why the planet lost most of its once-thick atmosphere. Cloudspotting on Mars is a Zooniverse citizen science project.