NASA’s powerful new space observatory, the James Webb Space Telescope, was pelted by a larger-than-expected microscopic meteor at the end of May, causing some detectable damage to one of the spacecraft’s 18 primary mirror segments. The effect means the mission team will have to correct the distortion from the hit, but NASA says the telescope “continues to operate at a level that exceeds all mission requirements.”
NASA’s James Webb Space Telescope, or JWST, is the agency’s powerful next-generation space telescope, designed to look into the farthest regions of the universe and see the stars and galaxies that formed after the Big Bang in time. It cost NASA nearly $10 billion to build and over two decades to complete. But on Christmas Day 2021, the telescope was finally launched into space, where it was a very complicated process before it reached its final destination about a million miles from Earth.
Since its launch, JWST has already been hit by at least four different micrometeorites, according to the NASA blog, but all were small and about the size of what NASA expected the observatory would encounter. A micrometeorite is usually a small part of an asteroid, usually smaller than a grain of sand. However, the plane that struck JWST in May was larger than the agency had prepared, although the agency did not specify its exact size. NASA acknowledges that the strike, which occurred between May 23 and May 25, caused a “marginally detectable impact on the data” and that engineers continue to analyze the impacts of the collision.
NASA predicted that the James Webb space planet would collide with small space particles during its lifetime; Fast-moving space rock patches are just an inevitable feature of the deep space environment. In fact, NASA designed the telescope’s gold-plated mirrors to withstand the blows of tiny space debris over time. The space agency also combined simulations and Earth testing with mirror samples to determine the best way to strengthen the mirrors to withstand the impacts of micrometeorites. However, NASA says that the models they used for these simulations did not have a meteorite this small, and it was “beyond what the team could have tested on Earth.”
However, this does not come as a complete surprise. “We’ve always known that Webb must contend with the space environment, which includes harsh ultraviolet light and charged particles from the sun, cosmic rays from alien sources in the galaxy, and accidental strikes by micrometeorites within our solar system,” Paul Geithner, technical and deputy project director, said. at NASA’s Goddard Space Flight Center in a statement.
Engineers also have the ability to maneuver JWST’s mirror and instruments away from showers of space debris, if NASA can see them coming. However, the problem was that this exact meteor was not part of the shower, so NASA deemed it an “inevitable coincidence event.” However, the agency is putting together an engineering team to come up with potential ways to avoid or reduce the effects of micrometeorite strikes of this size. And because JWST is so sensitive, the telescope will also help NASA get a better understanding of how many micrometeorites there are in the deep space environment.
Despite the blow, NASA remains optimistic in its post about the future of JWST. According to the blog, “Webb’s early life performance still far exceeded expectations, and the observatory is fully capable of performing the science it was designed to achieve.” Engineers can also adjust the affected mirror to help de-distort the data. The mission team has already done this and will continue to tinker with the mirror over time to get the best results. It is a process that will continue throughout the JWST’s planned life of five to 10 years as new observations are made and events unfold. At the same time, NASA warns that engineers will not be able to completely cancel out the impact of the strike.
NASA engineers had to build the JWST to be incredibly powerful because the telescope is self-contained in space. Unlike its predecessor, the Hubble Space Telescope, which is currently in Earth orbit, the JWST was not designed to be serviceable. This means that if something big happens to the spacecraft, engineers will have to explore a way to fix it from Earth. There is no possibility at present to send humans or robotic spacecraft to modify the JWST. This means that JWST will have to live with its lightly damaged mirror until the end of its mission, and NASA expects the spacecraft to be exposed to more debris over time.
In the meantime, the strike does not appear to affect the JWST schedule. In fact, news of this microscopic meteor comes only a month before a major mission accomplishment. After spending the past few months precisely calibrating the JWST instruments and precisely aligning the spacecraft’s mirrors, the mission team is preparing to unveil the first full-color images from JWST on July 12. NASA won’t say what the images will be, but they should be amazing.