Since its launch, the James Webb Space Telescope (JWST) has been struck by at least 19 small space rocks. But one small rock in particular, a larger-than-expected micrometeorite, had a major impact on NASA’s newly commissioned Deep Space Telescope.
Now the space agency has published images of the mirrors of its telescope in addition to the first results of its analysis. Earlier in June, NASA revealed the impact of the micrometeorite.
Fortunately, although the size of the space particle was larger than the team had predicted, the damage was limited to just one of the observatory’s 18 mirrors – Mirror C3 – as seen in images included in a comprehensive new status report that is in the prepress database has been published arXiv.org.
Great performance from the James Webb Telescope
The impact, caused by a micrometeorite that struck the James Webb Space Telescope likely between May 22 and 24, left “unrecoverable” damage to a small portion of this mirror, according to the report. However, as reported live sciencee, this small dent does not appear to have affected the performance of the telescope at all. In fact, the James Webb’s performance “almost completely exceeds” expectations, the researchers said.
(The damage can be seen in the lower right corner of the image.)
Yet NASA scientists are still trying to estimate the true impact that impacts from micrometeorites like this one could have on the operations of the observatory, which, based on fuel consumption, should last 20 years in space.
Collisions “in line with expectations”
Similarly, the researchers said micrometeorite impacts were expected long before the telescope was launched.
“Every spacecraft will inevitably encounter micrometeorites,” the report states. “During the launch, wavefront sensors recorded six localized surface deformations in the primary mirror that are attributed to micrometeorite impacts.”
These biases occurred at a “rate of approximately one per month,” according to the report, which is “consistent with pre-launch expectations.”
During construction of the JWST, engineers reportedly intentionally hit mirror samples with micrometeorite-sized objects to see how those impacts would affect the telescope’s performance.
Previous models wrong?
Now scientists are trying to get ahead of the problem by examining whether the C3 collision was a “rare event” that only happens “once in several years” or whether pre-launch models were wrong about the frequency regarding such events.
Still, pending further analysis and despite the unexpected impact on mirror C3, the researchers found that after six months of operation, the telescope is running smoothly and has a bright future of discovery ahead of it.
The JWST was designed “to enable fundamental advances in our understanding of the formation and evolution of galaxies, stars and planetary systems,” says the report. “Now we know for sure that it will be.”
Edited by Felipe Espinosa Wang.