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DISCOVERMAGAZINE.COM
FAR, FAR AWAY
THE CRUX
HIGH CLOUDS ON JUPITER
Looking a bit like earthly thunderheads, a white band of high-altitude clouds emerges above the colorful, swirling patterns of Jupiter in a photo
taken last summer by NASA’s Juno spacecraft. Jupiter, the solar system’s largest planet, has no Earth-like surface. Instead of an outer crust, the gas
giant consists mainly of hydrogen and helium that condenses into liquid the deeper you go, all wrapped in an atmosphere of clouds made up of
ammonia ice, ammonium hydrosulfide crystals and ice water vapor. Measurements taken by Juno suggest the atmosphere extends nearly 2,000 miles
below the gaseous surface. The solar-powered spacecraft eased into a 53-day orbit around Jupiter in 2016 for a mission expected to last into 2021.
— ERNIE MASTROIANNI; PHOTO BY NASA/JPL-CALTECH/SWRI/MSSS/KEVIN GILL