The Mid-Infrared Instrument (MIRI) on the James Webb Space Telescope (JWST) has four observing modes, one of which is medium-resolution spectroscopy (MRS). This part of the instrument has a rotating diffraction grating wheel which allows each part of the spectrum to be observed in short, medium, and long wavelength bands. On 2022-08-24, during configuration for an observation, the instrument reported increased friction when an attempt was made to rotate it to select the desired band. On 2022-09-06 and anomaly review board was convened to investigate the problem and recommend how to proceed. It has not yet reported on its findings, and MIRI observations in MRS mode remain suspended.
Other Webb instruments and the remaining three MIRI modes remain operating normally.
Updates on the status of Webb’s instruments are posted on NASA’s Webb blog.