James Webb damaged in micrometeoroid impact, image quality remains high
The James Webb Space Telescope (JWST) has suffered a new setback, sustaining a micrometeoroid impact to one of its mirror segments. While larger than the impacts anticipated during ground testing, the science team says that the telescope should still be able to perform the tasks it was designed for.
Although space seems mostly empty, dust and debris are known to be floating around out there. Even tiny particles can damage spacecraft if they’re traveling at high speeds, and James Webb’s tennis-court-sized primary mirror makes for quite a large target. As such, extensive modeling and testing of impacts was conducted during design and construction of the telescope, to ensure that it could withstand the expected bombardment of micrometeoroids over its lifetime.
Between May 23 and 25, the JWST sustained an impact to one of its mirror segments, C3, which was larger than had been accounted for. Analysis and measurements are ongoing to assess the damage and how it may affect the science mission.
“With Webb’s mirrors exposed to space, we expected that occasional micrometeoroid impacts would gracefully degrade telescope performance over time,” said Lee Feinberg, optical telescope element manager of the JWST. “Since launch, we have had four smaller measurable micrometeoroid strikes that were consistent with expectations and this one more recently that is larger than our degradation predictions assumed.”
While the effect on the data will be detectable, it should be relatively minor, the science team says. The position of the affected mirror has been adjusted to cancel out some of the distortion, with more fine-tuning planned to see if it can be improved further.
The even better news is that on the whole, the JWST will still perform at a level that exceeds its original expectations, even with the damage. Most importantly, the team says that the impact will not change the schedule for the release of the first full-color images and spectroscopic data, which is still set for July 12.