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7 asteroid impacts on Earth

By: Katherine Butler on Nov. 25, 2012, 12:07 p.m.
Lake Bosumtwi crater

Photo: NASA

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Bosumtwi Crater, Ghana

The Lake Bosumtwi impact crater was formed about 1 million years ago and is a sacred spot to the Ahshanti, who believe the dead come here to bid farewell to the god Twi. Fishing in the lake is allowed, but only from wooden planks and not modern boats, because there's a taboo against touching the water with iron.

Located in a dense rainforest, this African crater has been hard to study, but experts have confirmed that its creation was the result of an impact.

Its rim diameter is about 11 kilometers measured north to south and 10 kilometers east to west, according to the Geological Society of America Bulletin. The largest impact crater on Earth is thought to be the Wilkes Land crater in the Antarctic. However, experts cannot confirm this because the crater is buried under 2 kilometers of ice.

Most impact craters eventually erode away; however, as seen here, the truly magnificent impacts still remain.

There are as many as 140 individual impact craters on Earth. NASA estimates that accounts for about 25 percent of all the craters that exist — but most have yet to be discovered.