Three of the four instruments on NASA’s Webb telescope ready for science

Three of NASA’s James Webb Space Telescope’s four science instruments have completed commissioning and are ready for science.

Each of Webb’s instruments has several modes of operation that must be tested, calibrated, and finally verified before they can be used for science. The Near-Infrared Spectrograph, or NIRSpec, is the most recent instrument to complete this process, and it has four key modes that the team has officially confirmed are ready to go.

“NIRSpec is now ready for scientific use! This is an incredible moment, the result of more than two decades of hard work by many JWST and NIRSpec people and teams. I’m so proud of everyone “said Pierre Ferruit, ESA (European Space Agency) Webb project scientist and NIRSpec principal investigator. “It is now time for science, and I am looking forward to seeing the first scientific results from NIRSpec observations. I’m confident they’ll be fantastic. Thank you to everyone who has helped make this possible over the years—excellent work!”

The multi-object spectroscopy mode was the final mode validated for NIRSpec, a critical capability that allows Webb to capture spectra, or rainbows of infrared light, from hundreds of different cosmic targets at once. In multi-object spectroscopy mode, NIRSpec can open and close approximately 250,000 small shutters, each about the width of a human hair, to view some parts of the sky while blocking others. Webb can observe multiple specific targets while reducing interference from others by controlling this “micro shutter array.”

This is the first time NIRSpec’s multi-object spectroscopy mode has been validated for use from space. It will enable NIRSpec to characterise everything from the universe’s faintest objects to the formation of galaxies and star clusters.

NIRSpec was built for ESA by a consortium of European companies led by Airbus Defense and Space, with the detector and microshutter subsystems provided by NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Only one of Webb’s four instruments’ 17 total instrument modes, the Near-Infrared Camera, has yet to be verified (NIRCam). The months-long process of preparing Webb for science will be formally completed when the team confirms this remaining mode.

Webb’s commissioning process will conclude on July 12 with the release of the telescope’s first full-color images and spectroscopic data, marking the start of the telescope’s science mission.