A large unexpected meteoroid struck the James Webb Space Telescope at the end of May, leaving a dent on its gold-coated mirror.
The James Webb Space Telescope, launched by NASA on December 25, 2021, has now collided with at least 19 small meteoroids, including one sizable enough to cause noticeable damage to one of its 18 gold-coated mirror segments, according to a report on the arXiv.org database on July 12.
A large meteoroid struck mirror C3 of the James Webb Space Telescope, causing permanent damage (bright white spot on the lower right corner of the mirror segment). (Image: NASA/CSA/ESA)
In the report, NASA experts shared the first images showing the extent of the damage. On mirror segment C3 in the lower right corner, the impact site appears as a bright white dent prominently displayed against the gold-coated mirror surface.
The collision likely occurred between May 23 and May 25, leaving “irreparable” damage to a small portion of the mirror, the team of experts stated. However, this small dent does not seem to hinder the operation of the James Webb. In fact, the telescope’s performance is exceeding expectations.
These micrometeoroids pose a familiar threat to spacecraft in low Earth orbit. The U.S. Space Surveillance Network tracks over 23,000 objects in orbit larger than a softball, but there are millions of smaller objects that are nearly impossible to track.
As a result, NASA and other space agencies prepare in advance to deal with inevitable collisions. “Any spacecraft will face micrometeoroids,” the expert team stated on arXiv.org.
So far, six micrometeoroids have left noticeable deformation marks on the James Webb mirrors, equivalent to one significant impact per month since its launch. This number remains within expected parameters. During the development of James Webb, engineers proactively used objects the size of micrometeoroids to strike mirror prototypes to test how such impacts would affect the telescope’s functioning.
However, the surprising aspect is the size of the meteoroid that dented mirror C3. This meteoroid appears to be larger than experts had anticipated. Currently, they are working to assess the potential impact that similar collisions may have on the James Webb in the future.
Despite the unexpected collision with mirror C3, researchers have found that the James Webb is still operating well after six months of testing and has a promising future. “James Webb was developed to provide breakthroughs in our understanding of the formation and evolution of galaxies, stars, and planetary systems. Now we are confident it will achieve that,” they concluded.
