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Our Glaciers: Then and Now activity kit helps you see the changes taking place in glaciers around the world. See all our activity kits and classroom activities.
This image shows a Small Comet streak (in yellow box). This image was captured by the IRO on January 20, 1999. The longer black streaks are star trails.
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Courtesy of Dr. Louis A. Frank, The University of Iowa and NASA

Small Comets Bring Water to Earth
News story originally written on March 1, 2001

There are small snow comets that crash into the Earth's atmosphere. About 20 snow comets weighing 20 to 40 tons each crash into the Earth's atmosphere every minute!

Scientists have seen these small comets in spacecraft images. They have also seen the comets using the Iowa Robotic Observatory (IRO) in Arizona.

The comets are no danger to life on Earth because they fall apart in the atmosphere. In fact, some scientists think that the water in the Earth's oceans might have arrived by way of these small snow comets. And that would have been helpful to life on Earth!


Last modified February 28, 2001 by Jennifer Bergman.

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