At first listen, Earth’s stratosphere seems calm and quiet. But when researchers launched solar-powered balloons up 70,000 feet, they detected a hidden acoustic world — including mysterious noises without a known origin. The noises are “infrasound,” inaudible to the human ear — just as light in the infrared spectrum is invisible to the human eye. When recorded with…
This story from washingtonpost.com was posted on 2023-05-12 by @alpinec.