Asteroid Dust May Influence Weather

[zavvy]

<b>Asteroid Dust May Influence Weather</b><br /><br />LINK<br /><br />Dust from asteroids entering the atmosphere may influence Earth's weather more than previously believed, researchers have found. <br /><br />In a study to be published this week in the journal Nature, scientists from the Australian Antarctic Division, the University of Western Ontario, the Aerospace Corporation, and Sandia and Los Alamos national laboratories found evidence that dust from an asteroid burning up as it descended through Earth's atmosphere formed a cloud of micron-sized particles significant enough to influence local weather in Antarctica. <br /><br />Micron-sized particles are big enough to reflect sunlight, cause local cooling, and play a major role in cloud formation, the Nature brief observes. Longer research papers being prepared from the same data for other journals are expected to discuss possible negative effects on the planet's ozone layer.<br /><br />"Our observations suggest that [meteors exploding] in Earth's atmosphere could play a more important role in climate than previously recognized," the researchers write.<br /><br />Scientists had formerly paid little attention to asteroid dust, assuming that the burnt matter disintegrated into nanometer-sized particles that did not affect Earth's environment. Some researchers (and science fiction writers) were more interested in the damage that could be caused by the intact portion of a large asteroid striking Earth. <br /><br />But the size of an asteroid entering Earth's atmosphere is significantly reduced by the fireball caused by the friction of its passage. The mass turned to dust may be as much as 90 to 99 percent of the original asteroid. Where does this dust go?<br /><br />The uniquely well-observed descent of a particular asteroid and its resultant dust cloud gave an unexpected answer.<br /><br />On Sept. 3, 2004, the space-based infrared sensors of

 

[rhodan]

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