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James Webb is currently undergoing a cryogenci vacuum test in a very large chamber

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called Chamber A at NASA Johnson Space Center

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and the purpose of this test to make sure that all the components of the telescope

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are going to function in the cold vacuum environment of space

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Title: Nithin Abraham, NASA Coatings engineer. Abraham: I'm a coatings engineer and I'm working very closely

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with the James WEbb Contamination Control team. Before we start the 

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cryogenic test, the contamination control team works to clean the inside of the chamber so

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Webb can stay as contamination free as possible. It's not possible

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for anyone to access the chamber during the test so, we have to

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do all our contamination mitigation before the test starts. 

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and my job specifically involves the development and testing of

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a new NASA coatings technology that can help mitigate 

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molecular contamination concerns. So, the plenum is an area at the 

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bottom of Chamber A, its the space directly below where Webb sits

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ready for testing. To get tot he plenum, we have to carefully walk

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in the space between the helium shroud, which is surrounding Webb, 

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and the outer wall of Chamber A. There's no lights so we have to

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wear headlamps. The plenum is considered a confined space becuase

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there's only one way in, and only one way out. We have to wear oxygen

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sensors to make sure that it's safe to be down there. We have to

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take a ladder down to the plenum, that's the lowest level at the bottom of the chamber.

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And the floor, is actually the curved bottom of Chamber A.

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So there are molecular contaminants that exist in the plenum

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for example you have your hydrocarbons and your silcones and 

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these are sometimes very difficult to remove almost completely,

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and the contamination team has done an amazing job of reducing the 

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existing levels down to a very minimal amount and it's

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this residual contaminants that can essentially out-gas during 

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vacuum testing, spread throughout the chamber, and perhaps even deposit on a

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very cold. sensitive surface such as James Webb. Graphic: Molecular Adsorber Coating is a highly pourous material that can be sprayed onto surfaces

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to passively capture molecular contaminants. Abraham: to tackle the problem at the source and 

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that's why we placed the MAC samples in the plenum area.

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We do a thorough analysis on the types of contaminants that

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were collected and how much, the data is very useful and shows that 

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we are protecting James Webb from molecular contamination

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I've devoted a lot of my early career developing and testing

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this coating, and I'm really happy to see it being used on a lot of flight projects.

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beep beep  beep beep

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