A winter mystery

last updated 8 January 2015

Brainerd, Minn.

The “black hole” of North Long Lake is back. A patch of the frigid Minnesota lake has failed to freeze over for the second year running, and no one knows why. Readers of the local newspaper, The Brainerd Dispatch, suggested the 2,000-by-400-foot hole was caused by volcanic activity, space junk, or a spaceship. “A meteor ain’t that far-fetched,” another man said. Scientists said warm runoff from heavy recent rains could be seeping up from an aquifer below the lake. Last winter, a dozen snowmobilers sped into the gap, so this year officials sent divers to investigate. Diver Todd Mathies said he was stumped, although he ruled out one theory: “There were no spaceships down there.”