While telescope alignment continues, Webb's Mid-Infrared Instrument (MIRI) is still in cooldown mode. MIRI, which will be the coldest of Webb's four instruments, is the only instrument that will be actively cooled by a cryogenic refrigerator, or cryocooler. This cryocooler uses helium gas to carry heat from MIRI's optics and detectors out to the warm …
After meeting the major milestone of aligning the telescope to NIRCam, the Webb team is starting to extend the telescope alignment to the guider (the Fine Guidance Sensor, or FGS) and the other three science instruments. This six-week-long process is called multi-instrument multi-field (MIMF) alignment. When a ground-based telescope switches between cameras, sometimes the instrument …
This week the Webb team continued to make progress in aligning the telescope to the NIRCam instrument. Between taking the data to understand the optical components, we continue to check out the science instruments. The NIRSpec instrument includes a microshutter array of a quarter-million miniature movable windows, each 0.1 by 0.2 millimeters in size. The …
This week, the Webb team has been working on the fourth stage of mirror alignment, called Coarse Phasing, which measures and corrects smaller height differences between the mirror segments. In the meantime this past week, Webb's Near-Infrared Spectrograph (NIRSpec) team successfully finished the check-out and initial characterization of three crucial onboard mechanisms. Today, members of …
