* Astronomy

Lessons being learned from massive impact craters on Earth and beyond could help settle the question of whether such a crater exists in the eastern Hudson Bay.
Any map of Hudson Bay shows a suspicious, semi-circular coastline in northwestern Quebec. The Belcher Islands, just to the west of that curved coast, might be the remnants of a central peak — a common feature of impact craters on the moon and elsewhere.
What's more, past work has suggested that when recent rifting of the land near the crater site is accounted for, even more of the circle — about two-thirds — would be visible.



But while the idea of a 450-km diameter Hudson Bay crater has been around for 40 years, there has been no conclusive evidence of its existence.
If such a crater exists, it would be the largest known on Earth. The current record-holder is the 112-mile-wide Chicxulub Crater on Mexico's Yucatan Peninsula.

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