NASA engineers at the Goddard Space Flight Center have successfully installed the delicate camera and spectrograph instruments onto the back of the James Webb Space Telescope's (JWST) mirror assembly. The instrumentation was contained within a single unit known as the Integrated Science Instrument Module (ISIM).

The final hexagonal section of the 21.4 ft (6.5 m) primary mirror was slotted into place on Feb 3, 2016, with the telescopic tripod mounted secondary mirror attached one month later.

With the mirrors installed, the next nerve-racking step for the team at Goddard was to attach the cutting edge instrumentation designed to record the light collected by the gold coated mirrors, and turn it into actionable observations.

Four scientific instruments are housed in the ISIM unit – the Near-Infrared Camera, Near-Infrared Spectrograph, the Mid-Infrared Instrument, and the Fine Guidance Sensor/Near Infrared Imager and Slitless Spectrograph. This primary payload will allow the JWST to make detailed observations of the earliest stars and galaxies, discover previously undetectable exoplanets, and carry out a wide variety of other functions.

It took two dozen engineers and some extremely precise crane-work to maneuver the hefty ISIM unit into place at the rear of the mirror assembly. Hardware for ISIM was extremely time consuming and expensive to develop and fabricate, and so a lapse in concentration from any engineer involved in the installation could have been catastrophic for the JWST.

"This is a tremendous accomplishment for our worldwide team," comments JWST Project Scientist and Nobel Laureate John Mather. "There are vital instruments in this package from Europe and Canada as well as the US and we are so proud that everything is working so beautifully, 20 years after we started designing our observatory."

The telescope assembly and scientific instrumentation contained in ISIM will be subjected to a series of acoustic and vibration tests, in an effort to ensure the health of the space telescope after what will undoubtedly be a bumpy ride into orbit.

A video displaying the interior of the ISIM unit can be seen below.

Source: NASA

View gallery - 2 images