Daniel Bowman from Sandia National Laboratories has developed low-cost solar-powered hot air balloons that detect unique sounds in the stratosphere, including enigmatic infrasound signals. Presented at the 184th Meeting of the Acoustical Society of America, this innovative approach allows researchers to capture low-frequency sounds from a relatively calm layer of Earth’s atmosphere, which is seldom disturbed by aircraft or turbulence. The balloons, constructed from painter’s plastic, shipping tape, and charcoal dust for thermal absorption, can rise over 70,000 feet using passive solar power. Each balloon, approximately 6 to 7 meters in diameter, costs around $50 to make and can be assembled in common spaces like basketball courts. Equipped with microbarometers originally designed for volcanic monitoring, these balloons track various natural and human-made sounds, such as ocean waves and wind turbine noise, while also detecting mysterious infrasound signals with unknown origins. The technology offers a cost-effective way to gather extensive data and could potentially be adapted for exploring other planets, including assessing seismic and volcanic activity on Venus through its dense atmosphere. This research opens new avenues in atmospheric science and planetary exploration.
