NASA Earth Observation: Manicouagan Impact Crater, Canada

Manicouagan Crater is one of the world’s largest and oldest known impact craters and perhaps the one most readily apparent to astronauts in orbit.

The age of the impact is estimated at 214 million years before present.

Since then erosion has removed about one kilometer (0.6 miles) of rock from the region and has created a topographic pattern that follows the structural pattern of the crater.

A ring depression (prominently seen as green) encloses a central peak.

The ring depression now hosts the Manicouagan Reservoir and so appears as a distinct ring lake to astronauts and as a smooth and flat feature in this topographic visualization.

A fine pattern of topographic striations trending south-southeast, most prominent within the crater itself, indicates the flow direction of glaciers that covered this area during the last ice age.

Read the full article here at NASA Earth Observation also available is a stereo and anaglyph version of this image.