Development of the highest altitude balloon Original Research Article

Development of a balloon flying at higher altitude is one of the most attractive trials for balloon technology. We, the balloon group at the Institute of Space and Astronautical Science (ISAS), have been engaged in the development of a light balloon to go to higher altitudes since 1991. We have developed light equipment for house keeping modules and an ultra-thin film with a thickness of only 3.4 μm. Using the equipment and film, we have made and launched some balloons from 1000 m3 in volume. We gradually enlarged the balloon volume, and on May 23, 2002, we launched a 60,000 m3 balloon. The balloon reached the altitude of 53.0 km, which is the highest altitude ever reached by a balloon. This event opened a new era for scientific observations at high altitude.