Credit: NASA’s Goddard Space Flight Center
Following Webb’s arrival at its orbital destination around Lagrange Point 2 (L2) on January 24, the mission operations team began working its way through a critical series of steps: powering on all the science instruments, turning off heaters to begin a long cooldown process, and ultimately capturing the first photons on Webb’s primary camera to enable a months-long alignment of the telescope.
While the MIRI instrument and some instrument components were powered on in the weeks after Webb’s December 25 launch, the team didn’t finish turning on the remaining three instruments – NIRCam, NIRSpec, and FGS/NIRISS – until the past few days.
The mission operations team’s next major step is to turn off instrument heaters. The heaters were necessary to keep critical optics warm to prevent the risk of water and ice condensation. As the instruments meet pre-defined criteria for overall temperatures, the team is shutting off these heaters to allow the instruments to restart the months-long process of cooling to final temperatures.
When NIRCam reaches 120 kelvins (approximately -244 degrees (function(d, s, id){
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