Radiosonde (image) University of Hawaii ‑ SOEST Caption This image shows a weather balloon on its voyage to the upper atmosphere. Launched once or twice a day from stations throughout the world, balloons are used to measure wind speed and direction up to 19 miles high. Credit Cliff Lawson, Radiosonde Museum. Usage Restrictions According to the policies of the Radiosonde Museum. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.