Article I: Large Asteroid Crater found in my home town

It is always interesting when something happens in a place you were born, lived a significant portion of your life or have some sort of connection.  Essentially tests are being run to see if this could be the 184th confirmed time a solid rock impacted the earth and made some big hole in the ground in a story originally from the Washington Post. The crater is approximately 3.5 miles wide and dates back to approximately 470-490 million years ago.  And it shows there was something in Decorah before some one put up a web cam on some bald eagles.  

This is a wonderful opportunity to teach children about several things.   I learned things just by reading the article.  There was believed to be a large collision in the asteroid belt between Mars and Jupiter in which several of the other 183 craters came from.

We can learn about geology and the various rock layers and formations.  I know from growing up there Decorah is primarily a limestone bed that was formed by a prehistoric sea (as is most of Iowa).  The ocean/sea would've been receding, gone or vaporized by the time of this collision.  So there is the opportunity to learn about plate tectonics  geologic time scale, and changes over time both globally and locally.

Furthering geology and even chemistry, this alleged crater was discovered by identifying quartz that formed due to impact.  By learning what chemicals are in rocks we can learn ways to identify things and how to design tests to use gross estimates on how to determine if rock is say limestone versus marble or volcanic or some other sedimentary process.

The biggest stretch is that because of the prehistoric ocean, we can learn about evolution in biology.  How certain forms that emerged from the precambrian and this time reappear through out all of life today.  How great periods of time gradual changes add up.  How extinction and respeciation or new speciation occur.  

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