Readers discuss a subglacial cavern, how language shapes the brain and more

Hello darkness, my old friend

A subglacial river has carved out a cavern hundreds of meters beneath the Kamb Ice Stream, a West Antarctic glacier. Inside the dark, water-filled “cathedral,” scientists found signs of life, Douglas Fox reported in “Journey under the ice” (SN: 4/22/23, p. 18).

Reader Bob Masta asked how much sunlight filters down through the ice above the cavern.

“Essentially no light gets through that thickness of ice. These are truly dark environments,” Fox says. “The ice is basically opaque, crammed with bubbles and inclusions. So it scatters light until, after a certain depth, there’s nothing left.”