A giant cloud belt in the southern half of Jupiter has apparently disappeared according to new photos of the planet taken by amateur astronomers.
Jupiter's trademark Great Red Spot, a massive storm that could fit two Earths inside, is typically found along the edges of the planet's Southern Equatorial Belt (SEB). When the southern cloud belt fades from view, the Great Red Spot stands out along with Jupiter's Northern Equatorial Belt of clouds in telescope views.
"It was evident to Jupiter watchers late last year that the planet was going into one of these SEB fading cycles, but then it was lost behind the sun for several months and naturally everyone who follows these things was eager to take images as soon as possible after its re-emergence in March," Wesley told SPACE.com in an e-mail.
"As it moves away from the sun (from our point of view) it will be possible to capture even better images and perhaps we will be watching later this year or next year when the SEB revival takes place. The timing of this revival is not known, but historically this is a very dynamic event with planet-wide outbreaks of violent storms around the SEB latitude and eventually clearing away the obscuring clouds to reveal the dark SEB once more," he added.
"Jupiter with only one belt is almost like seeing Saturn when its rings are edge-on and invisible for a time -- it just doesn't look right," wrote skywatcher Bob King of Duluth, Minn., in a May 10 entry of his blog "Astro Bob" while discussing Wesleyan's surprising Jupiter views.
Jupiter is currently shining very bright in the eastern sky before sunrise.
Wesley is a veteran Jupiter watcher and posted the new shots on his website. It was he who first spotted a dark blemish on the planet in July 2009 that pointed to an impact on Jupiter, most likely from a comet. Wesley also spotted a giant blizzard on Saturn that is currently raging.
"Jupiter is a joy to observe and image, its dynamic atmosphere and brightly colored clouds mean that every view is different to the last even from one day to the next, and driven by the internal heat from deep inside the atmosphere you can be sure there is always something violent and interesting going on," Wesley said.
Changes in Jupiter's weather are not uncommon.
Last year, astronomers announced that Jupiter's Great Red Spot – which has raged for at least 300 years – appeared to be shrinking. In 2008, other red spot-like storms (smaller than Great Red) showed changes as well, while activity in the Southern Equatorial Belt also appeared to slow down.
Jupiter is the largest planet in our solar system and no stranger to weird weather.
Earlier this year, astronomers announced that the gas giant likely has helium rain showers from time to time. Jupiter has also tended to grow a variety of new storms, or spots, with some even changing color between white and red during dramatic climate changes on the gas giant.
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