Spores Onboard a Stratospheric NASA Balloon and Its Complete Life Cycle.

The aim of this study was to demonstrate for the first time spore viability in the stratosphere through spore germination and its complete life cycle. These protozoan spores were flown by the National Aeronautics and Space Administration (NASA) Columbia Scientific Balloon Facility (CSBF) flight 667NT, launched from its base in Fort Sumner, New Mexico. spores were exposed to stratospheric conditions on board the NASA/CSBF 667 balloon flight for 9 h.