Travel 890 million miles through our solar system and you’ll arrive at Saturn’s moon Titan. You might feel strangely at home. It has large lakes, flowing rivers, and sandy dunes just like Earth. It has an atmosphere, clouds, and it even rains from time to time. Instead of water, the lakes, rivers, and clouds are made from chemicals called hydrocarbons. Even the sand in the dunes are hydrocarbons!
But one major thing has been absent—wind. Scientists have been able to take a close look at Titan since 2004. That’s when NASA’s Cassini spacecraft began orbiting Saturn. In all that time they have never seen even a ripple in any of Titan’s lakes. Scientists don’t know what to make of this. They know that there has to be wind—how could the dunes have gotten there without it?
One possible answer: it just hasn’t been the right season for wind yet. Seasons last for a long time on Titan—it takes seven whole Earth years to change seasons! Scientists think they have been looking at Titan during a quiet period. They think that the changing seasons could bring the wind they have been looking for.
And not just any wind, but maybe even hurricanes! On Earth, summertime heating of the ocean fuels hurricanes. Air and water vapor rising from the Sun-warmed ocean warms the air and causes it to rise. The rising air sucks more warmed air in. This new air swirls in to replace the rising air. The storm picks up speed and a hurricane is born.
On Earth, ocean heating changes with the season. Hurricanes come only during the warm months. Scientists think that the hydrocarbons in Titan’s lakes might do the same thing as the water in the oceans here on Earth. It just needs to be the right season. As the seasons slowly change on Titan, the Sun will begin to heat up the hydrocarbon lakes in its northern hemisphere. With that warmth could come wind and maybe even hurricanes.
Forecasting weather on Earth is hard enough. You can imagine how hard it is to predict weather somewhere else in our solar system! Still, if scientists are right, it could be an exciting summer on Titan.
Read “Planet X-treme Weather” on NASA’s Space Place to learn about the exciting weather elsewhere in our solar system. http://spaceplace.nasa.gov/planet-weather
Learn more about Saturn, it’s moons, and our solar system at http://solarsystem.nasa.gov/saturnkids.
Category: Education Archived