“One of the James Webb Space Telescope’s four primary scientific instruments, known as NIRISS, has concluded its postlaunch preparations and is now ready for science. NIRISS, which stands for Near-Infrared Imager and Slitless Spectrograph instrument, provides observing modes for slitless spectroscopy, high-contrast interferometric imaging, and imaging, at wavelengths between 0.6 and 5.0 μm over a 2.2′ x 2.2′ FOV. It will be used to investigate the following science objectives: first light detection, exoplanet detection and characterization, and exoplanet transit spectroscopy.
The final NIRISS mode to be checked off before the instrument was certified 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 cosmic source to create three distinctive spectra (rainbows), revealing the hues of more than 2,000 infrared colors 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, momentarily 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.”
PL, rumor on an astronomy blog is that the first mission is targeting Alpha Centauri system for planets.
Proxima Centauri (Alpha Centauri C) has three confirmed planets with one in the in the “Goldie Lucks” (not to hot, not to cold) zone.
Alpha Centauri A and B both have candidates in the same zone.
If we could get atmosphere information on any of those planets or candidates it would be big.
https://en.wikipedia.org/wiki/Alpha_Centauri#Planetary_system
Jose –
Chinese want to find some Goldie Locks planets also. They are claiming they will launch their own space telescope ‘Earth 2.0’ in 2026.