BONBON: balloon-borne experiments, atmospheric compounds measurements, flight of 1 April 2011

BONBON is a cryogenic whole-air-samplers operated by the workgroup of PD Dr. Andreas Engel at the University of Frankfurt. This sampler is brought into the stratosphere with large balloons launched by the French Space Agency CNES (Centre National d’Etudes Spatiales) and reach high altitudes up to 38 km. As airplanes can access only altitudes up to 21 km the balloons present a unique measurement platform for stratospheric measurements. To avoid contaminations from outgassing of the balloon or gondola parts (due to the low pressures and high radiation in the stratosphere) samples are preferentially taken during the slow descent of the balloon if the meteorological conditions permit it. The BONBON cryo-samplers consist of a Dewar which contains 15 stainless steel containers that are electropolished inside to provide a smooth and inert surface. The Dewar is filled with liquid Neon before the balloon flights and cools to about 27 K. This allows sampling of large amounts of air even if at low outside pressures because the containers work as cryopumps (almost all air components are condensed inside). Each container is sealed with a glass cap which can be broken to open it. Moreover the inlets contain a gold pipe which can be cold welded using a pyrotechnical device to seal the containers once a sufficient amount of air has been condensed. These actions are performed via telecommand at those altitudes, where samples shall be collected.
This flight is involved in the ENRICHED campaign.