A SPACEX DELIVERY CAPSULE MAY BE CONTAMINATING THE ISS
IN FEBRUARY 2017, a SpaceX Falcon 9 rocket lifted through low clouds, pushing a Dragon capsule toward orbit. Among the spare parts and food, an important piece of scientific cargo, called SAGE III, rumbled upward. Once installed on the International Space Station, SAGE would peer back and measure ozone molecules and aerosols in Earth’s atmosphere. Its older siblings (SAGEs I and II) had revealed both the growth of the gaping ozone hole and, after humans decided to stop spraying Freon everywhere, its subsequent recovery.
This third kid, then, had a lot to live up to. Like its environmentally conscious predecessors, SAGE III is super sensitive. Because it needs unpolluted conditions to operate optimally, it includes contamination sensors that keep an eye on whether and how its environment might be messing up its measurements. Those sensors soon came in handy: When the next three Dragons docked at the Space Station, over the following months, SAGE experienced unexplained spikes in contamination. Something on these Dragons was outgassing—releasing molecules beyond the expected, and perhaps the acceptable, levels. And those molecules were sticking to SAGE.
Outgassing, in earthly terms, is what makes a new car smell like a new car. “There are volatile chemicals in those new materials that migrate through the material to the surface," says Alan Tribble, author of Fundamentals of Contamination Control. You’re smelling escaped seat ingredients, in other words. Source
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