14 DAY TRIAL // A tremendous thunderstorm that formed in the atmosphere of the gas giant Saturn is wider than our entire planet, the results of a new study show. The investigation also determined why the storm formed now, when experts were expecting it later on.
Called the Great White Spot, the massive storm has been imaged in exquisite detail in the new research effort. Experts measured it to have a diameter of about 6,200 miles (10,000 kilometers), while its cloud trail extends all the way around the planet.
Powerful storms such as this one have been noticed to occur about once every 30 Earth years or so, with the past 135 years revealing signs of only 5 such events. But the new atmospheric event came about more than a decade ahead of schedule.
The reason for this periodicity is the fact that the northern hemisphere of Saturn is most tilted towards the Sun once every three decades. However, the latest storm started forming in December 2010, when the gas giant's orientation did not meet these criteria.
Researchers behind the new study were led by planetary scientist Georg Fischer, who holds an appointment at the Austrian Academy of Sciences, in Graz. He says that the storm packs as much energy as Earth gets from the Sun during an entire year.
To get a sense of just how much that means, the storm contains 365 times the energy needed to power up the entire world for a year. In order to arrive at these conclusions, the researchers studied the Great White Spot (GWS) using ground-based telescopes.
Additional observations were conducted using the NASA Cassini spacecraft, which has been surveying the gas giant, its rings and its moon since achieving orbital insertion around Saturn on July 1, 2004.
In a new paper accompanying the study, which appears in the July 7 issue of the journal Nature, the research team takes a critical look at some of the explanations for why GWS occur in the first place.
Over the years, many have proposed that the Sun influences the Saturnine atmosphere, providing the energy such a storm needs to function. But clouds patterns present in the GWS prevent sunlight from entering layers of the atmosphere where the storm forms.
“This points to the action of an internal heat source as the power for the winds,” comments Agustin Sánchez-Lavega, a planetary scientist and researcher at the Higher Technical School of Engineering of Bilbao, in Spain.
The Sun could still be playing a role in this, by changing atmospheric patterns in such a way that the heat flows coming from deep within Saturn are changed periodically, Space reports.