Space.com (September 24, 2010)
"The clouds are clearing on Titan as spring takes hold in its northern hemisphere, signaling a shift in the weather patterns on Saturn's largest moon, a new study finds.
"Titan is poised for a mostly sunny spring, one that will last seven Earth years, researchers have found. Seasons on Titan last so long because it takes the moon and Saturn about 30 years to orbit the sun. [New photo of Titan clouds.]
"Scientists analyzed data from the last six years of observations by NASA's Cassini spacecraft to piece together how Titan's weather cycle works. They found that conditions have changed since August 2009 - when the sun was directly over Titan's equator during its latest equinox..."
As the Lemming has written before, sometimes data shows that the mathematical models scientists developed to account for an earlier set of data don't fit what's really happening. Other times, they do. Either way, something's learned.
In this case, so far, it looks like the models are on the same page as the reality.
"...These findings match predictions by computer models developed by other researchers in the past. Rodriguez and his team combined those models with the actual Titan observations to understand Titan's evolving cloud patterns.
"Different cloud-formation mechanisms are likely at work in the different hemispheres, the researchers said...."
It a way, Titan is more like Earth than is Mars. Both worlds have a relatively thick atmosphere with lots of nitrogen, lakes, rivers, clouds and rain.
There are differences, of course:
"...Titan and its weather have intrigued scientists for decades. Some think Earth resembled Titan before life took hold — only not nearly as cold. Titan's surface averages 290 degrees below zero Fahrenheit (minus 179 degrees Celsius).
"Titan has a thick, nitrogen-rich atmosphere, and its surface features have been carved by the action of liquid hydrocarbons like methane, which is the chief component of natural gas here on Earth. Methane rain drizzles from Titan's clouds, pooling in frigid liquid lakes...."
Which brings up another point: Earth might have been more like Titan, only warmer, before runaway photosynthesis polluted this planet's atmosphere with that dangerously reactive gas, oxygen.
Sure: (Most) animals use oxygen these days - and (most) other organisms can endure it. But we're pretty sure it wasn't always that way. (April 9, 2010)
Change happens. And the Lemming is repeating himself again.
- "Life on Titan! Or, Not"
(June 7, 2010)
- "Animals That Don't Need Oxygen - It Gets Weirder"
(April 9, 2010)
- "Titan, Life Without Water, and 'Messing With Old Definitions' "
(March 24, 2010)