On June 1st, NIRISS experienced a timeout and was, therefore, not available for science observations. No prime or coordinated parallels were affected by this. Detailed diagnostics show the instrument was healthy and ready to be recovered. Shortly after, on June 3rd, an unrelated combination of factors during the guide star pointing and acquisition resulted in the Fine Guidance Sensor (FGS) set to unavailable. This triggered a pause in JWST science observations. The ensuing analysis demonstrated all checks and software responses were adequate, and we will evaluate whether minor adjustments to the procedure are needed moving forward. The observatory was never at risk. On June 4th, NIRISS and FGS were successfully recovered, and science observations have resumed normally. Skipped visits will generally be rescheduled. Principal Investigators who were impacted should contact their Program Coordinators (PCs) to evaluate the need to request a repeat observation using a Webb Operation Problem Report (WOPR).
June 6, 2023
The NASA James Webb Space Telescope, developed in partnership with ESA and CSA, is operated by AURA’s Space Telescope Science Institute.