Exposing Microorganisms in the Stratosphere (E-MIST) is a NASA study to determine if a specific microorganism could survive conditions like those on the planet Mars. The study transported Bacillus pumilus bacteria and their spores by helium-filled balloon to the stratosphere of Earth (~31 km above sea level) and monitored the ability of the microorganisms to survive in extreme Martian-like conditions such as low pressure, dryness, cold, and ionizing radiation.[1]
A test flight of the balloon and gondola was launched from New Mexico on 24 August 2014. A second, longer flight, took place on 10 October 2015.[2]
Khodadad 2017
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