MINNEAPOLIS - Minnesota is hardly immune to meteorite strikes like the one that impacted in Russia on Friday. However, experts say such disasters are very rare.
"Our best estimates are that something on the order of a dozen fist-sized chunks of meteorite hit Minnesota each year," said Calvin Alexander, Ph.D., University of Minnesota Professor of Earth Science. "There is no doubt that the area that is now the State of Minnesota has been hit by meteors big enough to form craters many times in its history. It is just we have not found any."
Alexander said the glacial cover of Minnesota that occurred 10,000 years ago is probably why no craters have been identified. Although there are no defined craters in the state, there have been meteorites found.
One such piece of celestial debris fell in Fisher, Minnesota, Polk County, in 1894. Alexander showed Kare11's Allen Costantini the display case in Pillsbury Hall at the University where the Fisher meteorite is on public view, along with a number of other space rocks. The Fisher meteorite is a "chondrite" meteorite which contains no iron, but has a black crust from its fiery passage through earth's atmosphere. The interior resembles low grade concrete.
A larger, heavier specimen in the case is a slice of meteorite found in 1961 in Champlin. It is a section of a bowling ball sized meteorite found by a man who kept it on his front porch for 26 years. Alexander said the man's wife tired of the object leaving rust stains on the porch and told him to find out what it was. He took it to the University of Minnesota where it was determined to be a meteorite, composed of iron and nickel.
A consortium of Universities contributed to a purchase price for the rock. Each of those entities was given a piece of the original meteorite. Meteorites are highly prized by collectors, researchers and museums.
Wisconsin has had its share of meteor strikes including one at Nugget Lake that kicked small amounts of gold and diamonds from the earth's interior. It is believed that is the source of the lake's name.
A more recent and personal encounter with a space visitor happened in 1996 in western Wisconsin. A man parked his car in his driveway one snowy October night.
"And he walked out the next morning and it looked like somebody had just hit the windshield with a baseball bat," explained Alexander. "There was this fractured area right near the top of the windshield."
The man found two small black-crusted rock pieces in the well of the windshield wipers. A check confirmed they were fragments of a meteorite that had fallen sometime during the night.
Alexander insisted that "the big ones are very rare. The small ones come in all the time." He added a caveat. "The big ones are incredibly damaging events, but they only come in every 50 million years or so. The last one happened 65 million years ago...so, we are kind of overdue, but these are random events," said Alexander.