Latest James Webb instrument has cooled down and is ready for calibration – IT Pro – News

The James Webb Space Telescope’s MIRI instrument has cooled to its operating temperature of below -266 degrees Celsius. MIRI was the last part to cool down, and with that James Webb is all set for calibration.

James Webb had been cooling to absolute zero since its launch on December 25, and the latter instrument recently reached its final temperature. NASA announced the milestone on this week† The space agency says the MIRI instrument reached a temperature of 7 Kelvin, or -267 degrees Celsius, on April 7. With this, James Webb is fully up to temperature and the calibration of MIRI can begin.

To achieve that temperature, an electric cryocooler† Webb’s other three instruments were previously cooled by a sun shield the size of a tennis court, with which they reached a temperature of around -233 degrees Celsius. However, MIRI, or the Mid-Infrared Instrument, needs a temperature of -267 degrees Celsius to detect infrared light.

Infrared radiation is heat radiation. Planets, galaxies and stars all emit infrared light, but so do other warm objects, NASA explains. Cooling the telescope prevents James Webb’s components from emitting infrared that interferes with its operation. MIRI detects infrared light with a longer wavelength than the other three instruments, and must therefore be even colder. That could not be achieved with passive cooling and the aforementioned solar shield. That is why the cryocooler was used, which cools MIRI with helium gas. Tweakers wrote earlier a background story about MIRIA and its active cooling.

Now that the telescope has cooled down, that doesn’t mean Webb can get to work right away. In the near future, team members will first create test images of stars and other known objects, which can be used for calibration and to verify the operation and functionality of MIRI. NASA will conduct these preparations along with the calibration of the other three instruments, so that Webb can hopefully deliver his first images this summer.