James Webb Space Telescope hit by larger than expected micrometeoroid

quote:

---

NASA’s new powerful space observatory, the James Webb Space Telescope, got pelted by a larger than expected micrometeoroid at the end of May, causing some detectable damage to one of the spacecraft’s 18 primary mirror segments.

The impact means that the mission team will have to correct for the distortion created by the strike, but NASA says that the telescope is “still performing at a level that exceeds all mission requirements.”

Since its launch, JWST has already been hit by at least four different micrometeoroids, according to a NASA blog post, but all of those were small and about the size of what NASA expected the observatory to encounter.

A micrometeoroid is typically a small fragment of an asteroid, usually smaller than a grain of sand. The one that hit JWST in May, however, was larger than what the agency had prepared for, “likely less than .1 millimeter,” a NASA spokesperson told The Verge in an email. NASA admits that the strike, which occurred between May 23rd and May 25th, caused a dimple in the mirror and a “marginally detectable effect in the data,” which engineers are continuing to analyze.

Engineers do have the capability to also maneuver JWST’s mirror and instruments away from showers of space debris, if NASA can see them coming. The problem, though, was that this micrometeoroid was not part of a shower, so NASA considers it an “unavoidable chance event.” Still, the agency is forming an engineering team to come up with ways to potentially avoid or lessen the effects of micrometeoroid strikes of this size.

---