Researchers have detected mysterious noises in Earth’s stratosphere that cannot be explained. Some of the sounds picked up by solar-powered balloons have clear sources, such as a low murmur resembling the distant sound of ocean waves. But other intermittent crackles have proved inexplicable. Known as “infrasound”, the noises are inaudible to the human ear. Scientists hope that by studying such recordings from Earth they may be able to understand other planets, including Venus, which Russian scientists studied in the 1980s.
Daniel Bowman, a principal scientist at the Sandia National Laboratories who creates and launches solar-powered balloons said: “I’ve been doing it for about 10 years now, and, you know, the fact that there’s mysterious sounds that I don’t understand is troubling, but it’s not like a revelation… And no, we don’t know what it is.” The balloons float into Earth’s stratosphere using materials found at ordinary hard ware stores and moving where the wind takes them.
