One More Earth Circle

May 02, 2008

This one is one of my favorites Earth circles. I've even spotted it out the window of aircraft. Can you guess what & where it is? (The answer will appear soon in Comments section).
By the way, there is a reason I've been obsessing lately about circular features on Earth. I was recently discussing them with a researcher Jay Melosh of the University of Arizona. He mentioned that he gets a lot of crazy emails from folks who search satellite imagery now available online. They are looking for circles to call their own. Craters, mostly, to explain this, that or the other pet theory or to name after themselves or their beloved departed parakeet.

Most, like the Richat Structure shown in a posting last week, are not necessarily craters at all. It turns out, instead, that  Earth has a variety of ways of drawing circles on herself. Some ways are mundane, like erosion. Others are more violent, like caldera eruptions. All of them seem to tickle the fancy of geometrically inclined brains like those of humans.

Comments

[Random Comment Generator]

This looks very Amazon-esque to me. Does the winner of the guessing contest get a free trip there???

[Larry O'Hanlon]

Yes! But you lose and I can't afford for anyone to win, so I'll reveal the answer. This circle is in Canada. It's one of the most prominent impact craters in the world: The Manicouagan Impact Structure in Quebec. Often it's seen white with ice and snow. More very impressive images of this feature from space can be found at http://www.unb.ca/passc/ImpactDatabase/images/manicouagan.htm

[Anne]

After reading somewhere that Earth is protected from meteors by her atmosphere, I got a map of the world, laid tracing paper over it and started tracing circles - it wound up looking like the moon!