* Astronomy

Canada military probes mysterious Arctic pinging noise

The sound, sometimes also described as a "hum" or a "beep", has been heard throughout the summer in Fury and Hecla Strait, legislative assembly member Paul Quassa told CBC, about 120km north-west of the hamlet of Igloolik.
The area is a narrow channel of water in Nunavut, which is the newest, largest and least populous territory of Canada, located next to Greenland.
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