July 6, 2011
Storm On Saturn Eight Times The Size Of Earth
NASA reported today that scientists analyzing data from its Cassini spacecraft have discovered close-up details of a Saturn storm that is eight times the surface area of Earth.
The Cassini spacecraft located the storm about 35 degrees north latitude on Saturn on December 5, 2010.
Cassini's imaging cameras show the storm wrapping around the entire planet covering about 2 billion square miles.
NASA said the storm is about 500 times larger than the biggest storm previously seen by Cassini during several months from 2009 to 2010.
Scientists studied the sounds of the new storm's lightning strikes and analyzed images taken between December 2010 and February 2011.
Data from Cassini's radio and plasma wave science instrument showed the lightning flash rate as much as 10 times more frequent than during other storms monitored since Cassini's arrival to Saturn in 2004, according to the space agency.
"Cassini shows us that Saturn is bipolar," Andrew Ingersoll, an author of the study and a Cassini imaging team member at the California Institute of Technology in Pasadena, California, said in a statement. "Saturn is not like Earth and Jupiter, where storms are fairly frequent. Weather on Saturn appears to hum along placidly for years and then erupt violently. I'm excited we saw weather so spectacular on our watch."
NASA said the storm generated over 10 lightning flashes per second.
Cassini detected 10 lightning storms on Saturn since the spacecraft entered the planet's orbit and its southern hemisphere was experiencing summer.
"This storm is thrilling because it shows how shifting seasons and solar illumination can dramatically stir up the weather on Saturn," Georg Fischer, the paper's lead author and a radio and plasma wave science team member at the Austrian Academy of Sciences in Graz, said in a statement. "We have been observing storms on Saturn for almost seven years, so tracking a storm so different from the others has put us at the edge of our seats."
NASA said the new details about the storm complement atmospheric disturbances described recently by scientists using Cassini's composite infrared spectrometer and the European Southern Observatory's Very Large Telescope.
The storm is the biggest observed by spacecraft orbiting or flying by Saturn.
Image 1: The huge storm churning through the atmosphere in Saturn's northern hemisphere overtakes itself as it encircles the planet in this true-color view from NASA's Cassini spacecraft. Image credit: NASA/JPL-Caltech/SSI
Image 2: These false-color images from NASA's Cassini spacecraft chronicle a day in the life of a huge storm that developed from a small spot that appeared 12 weeks earlier in Saturn's northern mid-latitudes. Image credit: NASA/JPL-Caltech/SSI
On the Net:
- For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini.
- California Institute of Technology