I enjoy knowing what the weather is like right now anywhere on Earth. So several times each day, I look over the latest images from GOES-8, a US geostationary weather satellite, to keep an eye on where it’s clear and where it’s cloudy. The photos are updated frequently, and can be clicked on to zoom over a particular location. The other day I explored a vast, cloudless region across central Canada and stumbled upon one of the oldest and largest impact craters on Earth. Called Manicouagon crater, it’s located in eastern Quebec province. This obvious, circular scar is 42 miles in diameter and was created about 205 million years ago when a three-mile diameter asteroid struck our planet. Scientists have found evidence of the impact in heavily shocked rock found at the site.
When the asteroid hit, it not only melted the local rock down to a depth of five miles, but also blasted hunks of earth and asteroid across the globe. The titanic nightmare of it all would have been witnessed by the early dinosaurs before they, well … croaked.
What’s left today is a large, circular lake, presently covered in snow, surrounding a central uplift that was the center of impact. Pay a visit to this curious ring yourself by going to: http://www.ghcc.msfc.nasa.gov/GOES/goeseastconus.html
Courtesy Earth Science Office in Huntsville, Alabama
View of Manicouagan crater taken by
the crew of STS-9 (Space Shuttle). The
wing of the shuttle is at left. /NASA