for National Geographic News
Jupiter's powerful weather jets—the giant planet's equivalent to Earth's jet stream—may be fired up by internal heat rather than radiation from the sun, a new study says.
A team of researchers found that Jupiter's jets seem to reach well beneath the visible cloud layer, which absorbs most of the sun's light. This suggests that the jets are being maintained by heat and winds near the surface of the planet itself.
The observations shed light on a longstanding debate over whether Jupiter's jets form in the "shallow" or "deep" atmosphere.
But the research could also unlock weather secrets on Earth, on other gas giants such as Saturn and Neptune, and even on Jupiter-like extrasolar planets that are being discovered at accelerated rates, the study authors say.
(Related: "First Proof of Wet "Hot Jupiter" Outside Solar System" [July 11, 2007].)
The research, led by Agustín Sánchez-Lavega from the Universidad del País Vasco in Spain, appears in tomorrow's issue of the journal Nature.
Eye on the Storm
Jupiter's jets—which are far more numerous and consistent than Earth's jet streams—dominate the circulation of the thick cloud layer that hides the interior.
What powers the jets and how they form vertical structures in the atmosphere, however, are "major open questions," the study authors note.
Scientists have proposed two basic models for the formation of the jets.
In the shallow scenario, the jets result from thunderstorms and other sun-driven events on the visible surface of the gas giant. In the deep scenario, Jupiter's internal heat drives the jets.
Opportunities to probe the jets are rare.
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