[Rockhounds] Massive meteor crater discovered beneath Greenland's ice is much older than thought

[Dora Smith]

What was going on in the solar system at that time?

I wonder how this affected recovery from the Chicxulub asteroid and from 
the Deccan traps, if they were even over yet?   The asteroid fell right 
in the middle of the Deccan Traps and changed the nature of that eruption.

One other thing.   The CNN article says the Greenland asteroid was 19 
miles or 31 km wide, and the Chixulub or whatever asteroid was 200 km 
wide.  I thought the Chixulub (I give up) asteroid was 6 miles across?   
Something seems mangled here.  If a hundred mile wide asteroid ever 
smashed into Earth, I suspect it would melt the planet and break off 
another moon.

Yours,

Dora Smith



On 3/9/22 4:21 PM, Kreigh Tomaszewski wrote:
> The age of a 31-kilometer (19-mile) wide meteorite crater discovered under
> a kilometer of Greenland ice had long puzzled scientists.
>
> The Hiawatha crater was exceptionally well preserved despite glacier ice
> being incredibly effective at erosion. Its state fueled talk that the
> meteorite might have hit as recently as 13,000 years ago.
> However, the crater, which is one of the world's largest, has now been
> definitively dated -- and it is much, much older. In fact, it slammed into
> the Earth just a few million years after dinosaurs went extinct, about 58
> million years ago.
>
> "Dating the crater has been a particularly tough nut to crack, so it's very
> satisfying that two laboratories in Denmark and Sweden, using different
> dating methods arrived at the same conclusion. As such, I'm convinced that
> we've determined the crater's actual age, which is much older than many
> people once thought," said Michael Storey, head of geology at the Natural
> History Museum of Denmark, in a news release.
> When the asteroid hit, the Arctic was covered in balmy rainforest with
> temperatures of around 68 degrees Fahrenheit (20 degrees Celsius). Local
> inhabitants would have included crocodiles, turtles and primitive
> hippo-like animals, said Storey, who was an author of a new paper on the
> crater published in the journal Science Advances.
> The Hiawatha impact crater could swallow up Washington DC and is larger
> than about 90% of the roughly 200 previously known impact craters on Earth.
>
> https://www.cnn.com/2022/03/09/world/crater-greenland-age-scn/index.html
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