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　　This is Scientific American — 60-Second Science. I'mLee Billings

　　Got a minute?

　　For most people, Jupiter's most recognizable—andmysterious—feature is the Great Red Spot. Forcenturies, astronomers have watched the storm spinacross the giant world's face.

　　But for planetary scientists, Jupiter's most distinctive mystery may be what's called the"energy crisis" of its upper atmosphere: how do temperatures average about as warm asEarth's even though the enormous planet is more than fives times further away from thesun?

　　All the sun's giant planets display this energy crisis, and those in chilly orbits around otherstars probably have it, too. So where does the energy to heat their upper atmospheres comefrom?

　　According to a new study, the energy must originate within the giants, get transportedupward and become amplified by turbulent storms. The finding appears in the journal Nature.

　　This offers a new window into Jupiter's depths, and should allow researchers to betterunderstand gas-giant atmospheres throughout the universe. And it's all connected to theGreat Red Spot.

　　Astronomers have long known that auroral displays can heat Jupiter's poles, where chargedparticles trapped in the planet's intense magnetic field slam into its upper atmosphere. Sometheorists thought this auroral heating could flow toward the equator to warm the planet's mid-latitudes. So, using NASA's Infrared Telescope Facility, astronomers observed Jupiter for ninehours, looking for these flows as thermal fluctuations in the planet's upper atmosphere.

　　But they saw none.

　　Instead, in Jupiter's mid-latitudes they spied a thermal spike 800 kilometers above the GreatRed Spot, where temperatures soared hundreds of degrees higher than the surroundings. Thebest way to explain this spike is from the swirling maelstrom below, where turbulentatmospheric waves must generate heat by crashing together like breakers on a windy beachshore. Though this must be a planet-wide phenomenon, it is most obvious directly overJupiter's largest, most powerful storm.

　　As alien as it seems, scientists have seen the same behavior on much smaller, gentler scaleshere on Earth, when thunderheads rising over mountain ranges create rippling waves that heatthe air above.

　　Thanks for the minute for Scientific American — 60-Second Science Science. I'm Lee Billings.