Mars Weather
Written by Fraser Cain
With a planet that has an atmosphere 1% as dense as our own, you'd think that Mars wouldn't have much in the way of weather. But you'd be wrong. In fact, Mars weather is some of the most dramatic in the Solar System.
The typical weather on Mars, is cold and clear. Temperatures in the summer in the southern horizon can rise as high as 20 degrees C in the daytime, and then plunge at night. Dust devils, spun up by the dramatic daily temperature changes cross cross the landscape.
NASA was happy to learn that the winds on Mars can be strong enough to keep the rovers free of dust. Just as they were worried that the Mars Exploration rover's solar panels would be clogged with dust, a brisk Martian wind came through and dusted them off. This has greatly extended the lifespan of the twin rovers, Spirit and Opportunity.
The weather on Mars in the wintertime is really cold, and clear. Temperatures at the poles can reach -140 degrees C in the depths of winter. Carbon dioxide in the atmosphere freezes out around the poles, forming a 1 meter layer of dry ice at the north pole (the colder south pole maintains a permanent 8 meter layer of frozen carbon dioxide).
Clouds are a regular occurrence on Mars, especially around the slopes of Olympus Mons, the largest volcano on Mars (and the whole Solar System).
Perhaps the most dramatic weather system on Mars are its dust storms. These can start out in a small region, but grow over time and merge with other storms until they obscure the entire planet. The Mars Exploration rovers were caught in a recent dust storm, and NASA engineers were worried that the dust would obscure the rovers' solar panels to the point that they wouldn't be able to generate enough electricity to heat their electronics.
Here's an article about how the Opportunity rover suffered through bad weather on Mars. And how ice clouds create shade on Mars.
Want to know the weather on Mars? Here's the daily weather report, and a NASA article about how space weather affects Mars.
Finally, if you'd like to learn more about Mars in general, we have done several podcast episodes about the Red Planet at Astronomy Cast. Episode 52: Mars, and Episode 91: The Search for Water on Mars.
Filed under: Astronomy
