Category Archives: Jovian Planets

Saturn’s bulging core implies moons younger than thought

Saturn’s moon Dione, foreground, appears darker than the moon Tethys because it has a lower surface albedo, as shown in a photograph taken from the Cassini spacecraft on March 23, 2010. At the time, Cassini was about 746,000 miles from Dione and about 1.1 million miles from Tethys. Credit: NASA/Jet Propulsion Lab   Freshly harvested data from NASA’s Cassini mission reveals that Saturn’s bulging core and twisting gravitational forces offer clues to the ages of the planet’s moons. Astronomers now believe that the ringed planet’s moons are younger than previously thought. “All of these Cassini mission measurements are changing our view of the Saturnian system, as it turns our old theories upside down. It takes one good spacecraft to tell us how wrong we were in the past,” said Radwan Tajeddine, Cornell research associate in astronomy and a member of the European-based Encelade (pronounced en-CELL-ad) scientific team that pored over.
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Why Jupiter’s Red Spot Won’t Die

Jupiter’s signature Great Red Spot is sort of the Doctor Who of storms: It just won’t die — even when it has been proven that it must die.  And now, for the first time, some fluid dynamicists have finally hit on some of the secrets to the giant storm’s longevity. “It’s the largest, most enduring storm in the solar system,” said Philip Marcus of University of California, Berkeley, in a presentation at the meeting of the American Physical Society’s fluid dynamics division in Pittsburgh on Monday. The Red Spot is about 24,000 km across, east to west, 12,000 km from north to south, and a mere 40 km deep. Its wind are roaring around at about 225 miles per hour and this incredible monster has been observed from Earth almost continuously for at least 150 years, he said. But based on all the modeling that’s been done to try and.
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Observations of an extreme-weather planet raise questions about hot Jupiters’ origins

HD 80606 b (rendered here) stands out amid the hundreds of exoplanets discovered recently because of its highly eccentric orbit. Researchers have studied how the planet’s temperature changes as it approaches, sweeps by, and moves away from its star. Credit: Courtesy of the researchers and JPL For centuries, the solar system was viewed as a standard blueprint for planetary systems in the universe, with a star (our sun) at the center of a circular track, and a planet orbiting within each lane. Smaller, rockier planets fill the interior lanes, and larger gas giants orbit further out. But over the last 20 years, more powerful telescopes have revealed, far from our solar system, a host of exotic systems with completely unexpected configurations. “Hot Jupiters,” for example, are massive “roaster” planets that circle scorchingly close to their stars. Scientists have puzzled over how these gas giants, which supposedly form far from their.
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Giant methane storms on Uranus

Uranus as seen by NASA’s Voyager 2 Credit: NASA/JPL-Caltech   Most of the times we have looked at Uranus, it has seemed to be a relatively calm place. Well, yes its atmosphere is the coldest place in the solar system. But, when we picture the seventh planet in our solar system invariably the image of a calming blue hazy disc that the spacecraft Voyager 2 took in 1986 comes to mind. However, all we have previously known about the atmosphere of Uranus has been ‘thrown to the wind’ with observations made last year. In August 2014 a group led by Imke de Pater pointed the Keck telescope at Uranus and were a little bit surprised to see storms raging. It wasn’t as though clouds haven’t been seen before, but the clouds they spotted last year were very much brighter than any seen before. The fact that the storms are bright.
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ALMA reveals planetary construction sites

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs. Credit: ALMA (ESO/NAOJ/NRAO)/M. Kornmesser   Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found the clearest indications yet that planets with masses several times that of Jupiter have recently formed in the discs of gas and dust around four young stars. Measurements of the gas around the stars also provide additional clues about the properties of those planets. Planets are found around nearly every star, but astronomers still do not fully understand how—and under what conditions—they form. To answer such questions, they study the rotating discs of gas and dust present around young stars from which planets are built..
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