What's the Latest Development?
A paper recently published in Icarus describes the life and death of a massive thunder-and-lightning storm on Saturn that was recorded by NASA's Cassini probe. First detected in December 2010, the storm appeared at 33 degrees north latitude and began moving west, with a spinning vortex trailing behind it, and eventually stretched around the entire planet until it literally ran into its own tail in June 2011 and began to sputter out. By August 28, after 267 days, the storm was done for good. It was the longest-running and largest storm of its type observed in Saturn's northern hemisphere to date.
What's the Big Idea?
It's the first time a weather phenomenon of this sort -- a storm that rings a planet completely and dies after running into itself -- has been observed anywhere in the solar system. Storms on Earth never get a chance to make it around the planet because of land features, such as mountains, that help break them up. Assuming a similar storm could appear on Earth at the same latitude, it would travel a path marked by Atlanta, Phoenix, Islamabad, and Damascus, among other cities.