University of the Basque Country researchers in Spain say they believe methane storms are common on Saturn's moon Titan.
The detailed exploration of Titan with space missions began a couple of years ago and the presence of bright polar clouds and dry riverbeds has intrigued astronomers since.
Ricardo Hueso and Agustin Sanchez-Lavega from the planetary sciences group at the university's engineering school say they believe the clouds and dry beds are due to giant storms of methane.
Titan is the largest satellite of the planet and the only moon in the system with an atmosphere dense in nitrogen, similar to that of the Earth.
The astronomers posit huge clouds of methane vapor form storms on Titan's surface, with the hydrocarbon compound playing a similar role to that of water on Earth. The scientists calculate such storms, which can reach heights of about 22 miles, produce dense clouds of methane and copious precipitation from the gaseous compound.
The precipitation, the researchers believe, generates accumulations and rivers of liquid methane, producing the canals that have been observed on the moon.
The research appears in the July issue of the journal Nature.
Copyright 2006 by United Press International
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