NASA engineer Acey Herrera recently checked out copper test wires inside the thermal shield of the Mid-Infrared Instrument, known as MIRI, that will fly aboard NASA’s James Webb Space Telescope. The shield is designed to protect the vital MIRI instrument from excess heat. At the time of the photo, the thermal shield was about to go through rigorous environmental testing to ensure it can perform properly in the extreme cold temperatures that it will encounter in space.

Herrera is working in a thermal vacuum chamber at NASA’s Goddard Space Flight Center in Greenbelt, Md. As the MIRI shield lead, Herrera along with a thermal engineer and cryo-engineer verify that the shield is ready for testing.

On the Webb telescope, the pioneering camera and spectrometer that comprise the MIRI instrument sit inside the Integrated Science Instrument Module flight structure, that holds Webb’s four instruments and their electronic systems during launch and operations.

Webb is designed to obtain images and spectra in infrared light that is invisible to the human eye. As a consequence, the Webb telescope and ISIM must be cooled to a very low temperature (-383 F or -230 C) in order to avoid being blinded by their own infrared emission. The MIRI operates over longer infrared wavelengths than the other Webb instruments and, as a result, must be made approximately 35 degrees colder than the rest of the ISIM. The MIRI’s thermal shield is critical to achieving this lower temperature for the MIRI.

Herrera said the copper wires he’s looking at are located inside the silver box, are important for regulating the temperature of a mock-up of the MIRI instrument enclosed by the shield.

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