NIRISS, one of NASA's James Webb Space Telescope's four primary scientific instruments, recently completed its postlaunch preparations and became ready for science.

A second of Webb's four main scientific instruments, the Mid-Infrared Instrument (MIRI), has completed its postlaunch preparations and is now ready to be used for science.

In order to make observations of the star's orbiting planets, MIRI's coronagraphic imaging capability, which uses two types of masks to deliberately block starlight from hitting its sensors, was the last MIRI mode to be selected.

Scientists are now able to directly detect exoplanets and study dust disks around their host stars in a way that has never been done before.

The MIRI instrument, along with Webb's three other instruments, initially cooled to about 90 kelvins (minus 298 degrees Fahrenheit, or minus 183 degrees Celsius) in the shade of Webb's tennis court-size sun shield.

Using an electrically powered cryocooler, the team dropped to less than 7 kelvins, just a few degrees above the lowest temperature matter could reach. As a result of these extreme operating temperatures, MIRI is able to deliver mid-infrared images and spectra with an unprecedented combination of sharpness and sensitivity.

We are thrilled that MIRI now operates as a state-of-the-art instrument with better-than-expected performance across all its capabilities. The MIRI commissioning team has done an amazing job in a short period of time. 

Scientists, engineers, managers, national agencies, and NASA have all contributed to making this instrument a reality today as MIRI begins to explore the infrared universe in ways and to depths never achieved before,' said Gillian Wright, MIRI European principal investigator at the UK Astronomy Technology Center, and George Rieke, MIRI science lead at the University of Arizona.

The MIRI project was developed as a partnership between NASA (Jet Propulsion Laboratory) and ESA (European Space Agency), with a consortium of European astronomical institutes participating for ESA.

After completing the postlaunch commissioning activities for NIRISS and MIRI, the Webb team will focus on completing the remaining two modes for its other instruments.

NASA's James Webb Space Telescope, a partnership with ESA and the Canadian Space Agency, will release its first color images and spectroscopic data on July 12, 2022.