Parts of Canada are quietly short on gravity. The standard story blames an ice sheet that pressed the crust down and vanished thousands of years ago, but satellites suggest that explains less than half of it. The rest comes from something churning far dee

Parts of Canada are quietly short on gravity. The standard story blames an ice sheet that pressed the crust down and vanished thousands of years ago, but satellites suggest that explains less than half of it. The rest comes from something churning far dee

Parts of Canada are quietly short on gravity. The familiar explanation blames an ice sheet that pressed the crust down and then melted away thousands of years ago. That story is partly true, but satellite measurements suggest it explains less than half of the Hudson Bay gravity low, with much of the rest likely tied to deeper mantle structure and slow motion inside the solid Earth. The region in question sits around Hudson Bay, a broad area wher…