An icy mystery deep in Arctic Canada BBC - Travel April 4, 2022 https://www.bbc.com/travel/article/20220403-an-icy-mystery-deep-in-arctic-canada Pingualuit Crater https://craterexplorer.ca/pingualuit-impact-crater/ Pingualuit Crater, Canada https://earthobservatory.nasa.gov/images/8472/pingualuit-crater-canada Yours, Paul H.