NASA’s Cassini spacecraft has captured an image of interstellar indigestion. The bus-sized satellite, orbiting the ringed planet Saturn, caught the massive gas giant as it “belched” long after scientists had thought the storm had passed.
Information gleaned from Cassini’s composite infrared spectrometer (CIRS) instrument revealed the storm sent temperatures in Saturn’s stratosphere sky-rocketing to approximately 150 degrees Fahrenheit (83 kelvins) above normal.
During this period, scientists at NASA’s Goddard Spaceflight Center noted an increase in the amount of ethylene gas. Scientists do not know where this colorless, odorless gas originated from as it is not typically found on Saturn.
Saturn’s “burp” of energy was detailed in a paper that will be published in the Nov. 20 issue of the Astrophysical Journal.
“This temperature spike is so extreme it’s almost unbelievable, especially in this part of Saturn’s atmosphere, which typically is very stable,” said Brigette Hesman, the study’s lead author and a University of Maryland scientist who works at Goddard. “To get a temperature change of the same scale on Earth, you’d be going from the depths of winter in Fairbanks, Alaska, to the height of summer in the Mojave Desert.”
The storm was detected by Cassini in December of 2010. The storm would eventually cover a region approximately the size of North America. The process, like many within the solar system, is cyclical, occurring once every thirty years or so (thirty years equals about one Saturn year).
The discovery included a number of “firsts.” It was the first Saturnian storm investigated by Cassini as well as the first that was observed at thermal infrared wavelengths. It was the CIRS that collected the infrared data which scientists used to take the planet’s temperature. CIRS also allows the team back on Earth to study phenomena that would otherwise be invisible.
Cassini is showing that there is still a great deal about Saturn that we do not know. When the ethylene spike occurred, it was 100 times greater than what scientists believed was even possible. This observation was confirmed by the McMath-Pierce Solar Telescope located on Kitt Peak in Arizona. The team is still trying to figure out where the ethylene came from but has already ruled out a reservoir deeper in Saturn’s atmosphere.
“We’ve really never been able to see ethylene on Saturn before, so this was a complete surprise,” said Goddard’s Michael Flasar, the CIRS team lead.
The Cassini-Huygens mission was launch in 1997 , with the Huygens lander touching down on Saturn’s hazy moon Titan in 2005. The mission is a cooperative endeavor between NASA’s Jet Propulsion Laboratory, the European Space Agency and the Italian Space Agency.
For more info on this discovery: http://www.esa.int/esaSC/SEMLPIMFL8H_index_0.html
For more info about the Cassini mission: http://www.nasa.gov/cassini