Nasa has spotted a mysterious methane cloud high in the atmosphere of Saturn's moon Titan. They say the phenomenon is similar to exotic clouds found far above Earth's poles. This lofty cloud, imaged by Nasa's Cassini spacecraft, was part of the winter cap of condensation over Titan's north pole. This cloud in the stratosphere over Titan's north pole  contains methane ice, which was not previously thought to form in that part of the atmosphere. Cassini first spotted the cloud in 2006. The newly identified cloud instead developed in the stratosphere, the layer above the troposphere. Earth has its own polar stratospheric clouds, which typically form above the North Pole and South Pole between 49,000 and 82,000 feet (15 to 25 kilometers) - well above cruising altitude for airplanes.
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Similar to exotic clouds found far above Earth's poles
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Was part of the winter cap of condensation over Titan's north pole
Like rain and snow clouds on @placeholder, those clouds form through a cycle of evaporation and condensation, with vapor rising from the surface, encountering cooler and cooler temperatures and falling back down as precipitation.
Other stratospheric clouds had been identified on @placeholder already, including a very thin, diffuse cloud of ethane, a chemical formed after methane breaks down.