New Scientist - August 12, 2009
A pulse in the atmosphere of Saturn's moon Titan can spawn methane clouds across the moon, new observations suggest. Although the cause of such atmospheric events is still unknown, it could explain some puzzling features seen by the only probe ever to land on Titan's surface.
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Now Brown and colleagues have found a possible explanation. The team spotted a vast cloud below Titan's equator that triggered cloud formation in regions across the southern hemisphere. Such events might be a way to deliver methane rain to arid regions like the Huygens landing site, which sits some 10° south of the equator. "We think that this is an important part of the story," Brown says.
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The team found that Titan appeared brighter on 13 April 2008, and on the following night, Mauna Kea's 8-metre Gemini North telescope revealed a large cloud centred some 30° south of Titan's equator.
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