MARCH 2005 ISSUE
Nils Peterson
student column
________________
Meteorites Never Yell 'Fore!'
And Other Tales From Space
Many people think of meteorites as huge rocks that come from the depths of space
to kill dinosaurs, but the reality is much less dramatic. Meteorite falls are
regular occurrences on planet Earth, and although it may not look like it, we
get pelted by them about as much as our pockmarked Moon does.
Of course, many hit oceans or end up slowly weathering away into oblivion, but more and more are being found by people every year. Thirteen meteorites have been found in Alberta, either as spectacular falls or accidental finds. Many more from around the world are in the University of Alberta collection.
APEGGA student member Jessica Norris, a U of A geology student, got to study
the Alberta meteorites under the supervision of Dr. Chris Herd, a meteorite researcher
and the collection's curator. “Even though most of these meteorites fell
decades ago, some have had very little research done on them,” Jessica
says.
Alberta In Their Sights
When it comes to meteorites, Alberta makes an excellent target. When a meteorite
falls it heats up in the atmosphere, glowing as it streaks towards the ground.
Researchers can then find the meteorite by talking to witnesses and using sky cameras, which constantly film the heavens from certain locations across the country. The U of A, in fact, is home to one of those cameras.
That Alberta is relatively flat and open allows for more witnesses — and a better chance of meteorites being caught on film.
 |
Welcome to Bruderheim This meteorite fell near Bruderheim, east of Edmonton, in 1960, Some pieces bounced onto the snow spraying dirt. |
One June morning, the Odyssium in Edmonton received a call from a local golf
course that had found a mysterious rock near one of its greens. Jessica went
with Dr. Herd and the Odyssium's Frank Florian to see it.
“After working
in a lab with no windows, driving around in golf carts was a nice change,” says
Jessica.
Golf courses are actually ideal places for finding meteorites. They are large, mostly treeless and well tended. The Kitchener meteorite was found on an Ontario golf course in 1998 — after narrowly missing a golfer on the sixth hole.
Unfortunately the rock Jessica went to see was just a large piece of coal. How it got onto the golf course is still a mystery.
Meteorite 101
Most of the real Alberta meteorites are chondrites, which are relatively common
as meteorites go, but three are members of the more rare iron group. So far Bruderheim
has been the largest, with over 300 kg of material, but generally meteorites
are quite small.
Meteorites are named after the nearest named place to their fall, so Alberta meteorites include Peace River, Innisfree and Vulcan. There is a meteorite named Edmonton too, which was found in the area where the city centre airport is now. It was discovered in the 1930s by a farmer ploughing his field, and he realized its weight made it a peculiar find. The farmer kept it on his mantel for years until his daughter convinced him to have the university look at it, where it was quickly recognized as a solid iron meteorite.
Several Alberta meteorites have gained scientific and historical notoriety. The Innisfree meteorite was so well documented on film in 1977 that its orbit around the sun before it hit the Earth was accurately calculated. It was only the third meteorite in the world to have its orbit described.
Another notable is Iron Creek, which was found by native peoples centuries ago. Called the Manitou Stone, it was revered for generations, until it was taken in the 1860s by missionaries who saw it as an impediment to their conversion of natives to Christianity. After a long stay at the Royal Ontario Museum it was brought back to Alberta, and now occupies a prominent place in the gallery of aboriginal culture at the Provincial Museum of Alberta, in Edmonton.
Meteorites aren't just valuable because they're rare. The ones formed deep in space tell us about our own planet's origins. Earth formed in much the same way — one lump of rock hitting another in a war of attrition that only the biggest survive.
And by using geochemistry and mineralogy, we can find out when and how our
favourite chunk of rock formed.
Author Credits
BY NILS PETERSON
University of Alberta
Student Contributor
(Geosciences)