Scientists have long been puzzled by the “ignorosphere,” a region of air at 37 miles above the Earth’s surface, inaccessible to planes and weather balloons. Now, engineers are developing a lightweight disc-like structure that harnesses sunlight to levitate, thanks to photophoresis – a phenomenon where light-driven motion creates an upward airflow.
Inspired by a 19th-century toy, this solar-powered device uses ceramic aluminum with a chromium base to float on photophoresis. When sunlight strikes the device, heat and pressure differences create an upward airflow, keeping it airborne. This technology has the potential to monitor the mesosphere, collect groundbreaking atmospheric data, and even predict space weather.
The concept is not new – physicist William Crookes invented a radiometer in 1873 that fed off sunlight. However, previous attempts were limited by technology. The new device uses recent advances in nanofabrication, constructing tiny squares with very small holes to amplify the photophoretic force. To their surprise, these thin discs exceeded their weight, causing them to levitate.
To validate the calculations, the team built a low-pressure chamber and simulated atmospheric conditions. The results showed that the devices remained aloft. Rarefied Technologies, led by CEO Ben Schafer, is working towards commercializing this technology. They aim to integrate communications systems into the discs to collect and send back weather data remotely.
This innovative technology could revolutionize mesospheric exploration, enabling swarms or arrays of photophoretic flyers to collect high-resolution atmospheric data on temperature, pressure, chemical composition, and wind dynamics.
Source: https://gizmodo.com/scientists-unveil-wild-new-way-to-explore-the-edge-of-space-2000642161