Canada's NIRISS ready to see cosmos in over 2000 infrared colours
Test detector image of the NIRISS instrument operated in its SOSS mode while pointing at a bright star. Each colour seen in the image corresponds to a specific infrared wavelength between 0.6 and 2.8 microns. The black lines seen on the spectra are the telltale signature of hydrogen atoms present in the star. NIRISS is a contribution from the Canadian Space Agency to the Webb project that provides unique observational capabilities that complement its other onboard instruments. (Credit: NASA, CSA, and NIRISS team/Loïc Albert/University of Montreal)
One of the James Webb Space Telescope's four primary scientific instruments known as the Near-Infrared Imager and Slitless Spectrograph (NIRISS), provided by the Canadian Space Agency, has concluded its post-launch preparations and is now ready for science.
The last NIRISS mode to be checked off before the instrument was declared ready to begin scientific operations was the single-object slitless spectroscopy (SOSS) capability. The heart of the SOSS mode is a specialized prism assembly that disperses the light of a star to create three distinctive spectra (rainbows), revealing the hues of more than 2000 infrared colours collected simultaneously in a single observation. This mode will be specifically used to probe the atmospheres of transiting exoplanets, i.e. planets that happen to eclipse their star periodically, dimming the star's brightness for a period of time. By comparing the spectra collected during and before or after a transit event with great precision, one can determine not only whether or not the exoplanet has an atmosphere, but also what atoms and molecules are in it.
With NIRISS post-launch commissioning activities concluded, the Webb team will continue to focus on checking off the five remaining modes on its other instruments. NASA's James Webb Space Telescope, a partnership with the European Space Agency and the Canadian Space Agency, will release its first full-colour images and spectroscopic data on .
Abridged text reprinted courtesy of NASA