Hey...Where did that come from?

I was google map surfing and came across this odd circle in Quebec that I dont recall.

Here is a close-up. How could I have missed this?

http://en.wikipedia.org/wiki/Manicouagan_Reservoir

http://en.wikipedia.org/wiki/Manicouagan_Reservoir#Manicouagan_impact_crater

http://toolserver.org/~geohack/geohack.php?pagename=Manicouagan_Reservoir&params=51_23_N_68_42_W_type:waterbody_region:CA-QC_scale:1000000

http://www.bing.com/maps/default.aspx?v=2&cp=51.383333~-68.7&style=h&lvl=9&sp=Point.51.383333_-68.7_Manicouagan%20Reservoir___