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Courtesy of NASA and the University of Iowa.
Snowballs Entering The Earth's Atmosphere?
News story originally written on June 20, 1997
New evidence has just been found that suggests that there might be such a thing as interplanetary snowballs. And these snowballs are spraying the Earth's atmosphere. NASA's Polar spacecraft is responsible for the findings.
Dr. Louis Frank of the University of Iowa led the team that made the discovery. The research team found that these snowballs could be up to the size of a small house! They are not dangerous to life on Earth, because the snowballs break apart while they are still very far away from the surface of the Earth.
The objects are mostly made up of water. The snowballs may contain organic material, material that supports life. They are thought to be comet-like objects which contain frozen water, and so are termed "dirty snowballs." These snowballs are entering the atmosphere at a rate of 5-30 snowballs per minute, or thousands of snowballs in a given day.
This finding has made the Polar spacecraft's first year in orbit very successful.
Last modified July 18, 2002 by Lisa Gardiner.
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