Meteorologists have been flying weather balloons since the late 19th century. They provide valuable information about the wind speed and direction, temperature and pressure, at different altitudes. Balloons drift with the wind, so retrieving their payload is challenging and collecting atmospheric samples has been a job for aircraft – until now.
A team from the 56th Japanese Antarctic research expedition led by Shin-Ichiro Higashino has tested a novel approach, combining a balloon with a drone. In a recent experiment, they launched a balloon carrying the Phoenix-S1 drone from the Antarctic ice sheet. The drone, which has a wingspan of 3m and weighs 10kg, hitched a ride all the way up to 75,000 feet, collecting samples and measurements on the way.
At maximum altitude the balloon burst, the usual fate of weather balloons. Controlled flight is impossible at this altitude, so the Phoenix parachuted down to thicker air before shedding the parachute and flying back to its launch point.
The Phoenix was designed by Kyushu University to cope with temperatures as low as -80C during the flight.
The samples of atmospheric aerosols are now undergoing microscopic analysis. Their exact composition will tell researchers more about the global air circulation at different altitudes.
Circulation is complex and affected by the hole in the Antarctic ozone layer, and the new data will help researchers understand the current pattern. Sometimes you do need a weatherman, with a balloon-drone, to know which way the wind blows.
