NASA astronaut Jessica Meir works on the Major Constituent Analyzer

iss062e103552 (March 20, 2020) --- NASA astronaut and Expedition 62 Flight Engineer Jessica Meir works on the Major Constituent Analyzer, a device that measures the orbiting lab’s atmosphere. The life support gear monitors a variety of major constituents, such as nitrogen, carbon dioxide and water vapor to ensure a safe breathing environment for the crew.