In accordance with a newly published paper, a group of scientists said that after mentioning the performance of the James Webb during its commissioning phase, the telescope reported problems that “cannot be corrected”. They added that the telescope also suffered a “small effect throughout, which is not yet measurable”.
“At present, the largest source of uncertainty is long-term effects of micrometeoroid impacts that slowly degrade the primary mirror,” the scientists said in the report.
The impact “exceeded prelaunch expectations of damage for a single micrometeoroid triggering further investigation and modelling,” the report further stated.
In June, following the asteroid attack, Nasa put out a statement that said Webb's mirror was “engineered to withstand bombardment from the micrometeoroid environment at its orbit around Sun-Earth L2 of dust-sized particles flying at extreme velocities”.
“While the telescope was being built, engineers used a mixture of simulations and actual test impacts on mirror samples to get a clearer idea of how to fortify the observatory for operation in orbit. This most recent impact was larger than was modelled, and beyond what the team could have tested on the ground,” Nasa said.