$10 billion Webb Telescope has been hit by space rocks 14 times, NASA says
When NASA sent the James Webb Space Telescope (JWST) a million miles from Earth last Christmas Day, it did so with one major concern: micrometeoroids.
Predictably, these tiny particles of space dust have already hit all 18 gold and beryllium segments of the $10 billion space telescope, causing irreparable damage not only oncebut 14 times NASA has revealed in a blog.
“We’ve had 14 measurable micrometeoroid hits on our primary mirror, and averaging one to two per month, as expected,” said Mike Menzel, chief webb mission systems engineer at NASA’s Goddard Space Flight Center in Greenbelt. , Maryland. “The resulting optical errors of all but one were well within what we had expected and expected when building the observatory.”
The outlier happened in may, when a micrometeoroid struck one of the gold-beryllium segments that make up JWST’s 6.5-meter main mirror. Classified as an “unavoidable fortuitous event”, it slightly misaligned the telescope. Engineers were able to adjust its 18 mirrors to correct the damaged segment.
Space is a dangerous place to operate, with constant threats including cosmic rays from the Universe as a whole, harsh ultraviolet light and charged particles from the Sun, and micrometeoroids moving at extreme speeds.
However, JWST engineers are already taking evasive action to reduce the risk of the valuable space telescope being further damaged. A work group at NASA concluded that the May 2022 strike was a rare statistical event, but the massive space telescope will therefore be away from what is now known as the “micrometeoroid avoidance zone.” This means minimizing the time it spends looking in the direction of orbital motion, which statistically has more micrometeoroids moving at much higher speeds.
A particularly risky period is a meteor shower, which is caused by particles left behind in the inner solar system by the casing fro. It’s a scenario that could become a real problem, especially in May 2023 and again in May 2024. when Webb crosses Halley’s Comet stream of meteorites.
“Micrometeoroids hitting the mirror head (moving in the direction opposite to the telescope’s motion) have twice the relative velocity and four times the kinetic energy, so avoiding this direction when possible will help prolong exquisite optical performance for decades,” Lee Feinberg said. , responsible for elements of the Webb Optical Telescope at NASA Goddard.
The result is a shake-up of the JWST schedule, with objects observed when it’s safest to do so rather than in order of scientific urgency. An exception to this will be targets in the solar system, which are much more time sensitive.
Webb – a $10 billion space telescope that sees into the infrared part of the spectrum – launched on Christmas Day 2021 and has since February orbited the L2 point about a million miles/1.6 million kilometers away of the earth.
I wish you clear skies and big eyes.