Even as the first images captured by Nasa’s space telescope James Webb – the world’s largest and most powerful of its kind – have amazed the world, scientists say the device suffered permanent damage due to a series of asteroid attacks in May.
According to a new published paper, a group of scientists said that after outlining 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.
On May 22, the James Webb Space Telescope’s primary mirror was hit by six micrometeorites. Of these, the sixth strike did considerable damage. Initially it was not considered too big, but now the new paper by scientists suggests it could be more serious than thought.
The impact “exceeded prelaunch expectations of damage for a single micrometeoroid triggering further investigation and modeling,” the report further stated.
Although the damage did not compromise the resolution of the primary mirror of the space telescope, engineers who designed the Webb are of the belief that the mirrors and sunshield will unavoidably slowly degrade from micrometeoroid impacts, the paper stated.
A possible fix could be to minimise time spent looking in the direction of orbital motion that statistically has higher micrometeoroid rates and energies, the paper further stated.
In June, following the asteroid attack, Nasa put out a statement that said the 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 modeled, and beyond what the team could have tested on the ground,” Nasa said.
The James Webb Space Telescope was built by Nasa in collaboration with the European Space Agency (ESA) and the Canadian Space Agency (CSA) at a cost of $10 billion.
Comprising one of the largest mirrors on a space telescope, Webb was launched on December 25, 2021, and since February has been orbiting the L2 point – nearly a million miles, or 1.6 million kilometres, from Earth.
