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The ISIM houses the four main instruments that will detect light from distant stars and galaxies, and planets orbiting other stars.



Instruments & The ISIM



 isim location on webb


 isim location on webb

Webb's instruments are contained within the Integrated Science Instrument Module (ISIM) which is one of three major elements that comprise the James Webb Space Telescope Observatory flight system. The others are the Optical Telescope Element (OTE) and the Spacecraft Element (Spacecraft Bus and Sunshield).

The ISIM is the heart of the James Webb Space Telescope, what engineers call the main payload. It houses the four main instruments that will detect light from distant stars and galaxies, and planets orbiting other stars.

The ISIM includes the following instruments:

ISIM Installation

 isim being installed on webb

A rare view of the instruments being lowered into the Webb telescope at NASA/Goddard.

The James Webb Space Telescope's science instruments were installed in a surgically precise operation. Read more about the ISIM installation on Credit: NASA/Chris Gunn

Video: Instrument Locations

IN DEPTH: Technical Details about the ISIM

 ISIM Components within the Observatory
ISIM's three regions.

Integrating four major instruments and numerous subsystems into one payload, the ISIM, is a daunting endeavor. To simplify integration, engineers have divided the ISIM into three regions.

The "region 1" component is the cryogenic instrument module. This chills the detectors down to 39 K, a necessary first-stage cooling effort so that the spacecraft's own heat doesn't interfere with the infrared light (a form of heat) detected from distant cosmic sources. The ISIM/OTE Thermal Management Subsystem provides passive cooling. Other devices will get the detectors even colder.

The "region 2" component is the ISIM Electronics Compartment, which provides the mounting surfaces and ambient thermally controlled environment for the instrument control electronics.

The "region 3" component, located within the Spacecraft Bus, is the ISIM Command and Data Handling subsystem, with integral ISIM flight Software, and the MIRI cryocooler compressor and control electronics.

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