NASA says a small space rock influenced the James Webb Space Telescope

In a new home far from Earth, the James Webb Space Telescope may not be as alone as it looks.

The pockets of the space occupied by the telescope are not a perfect vacuum. And now unavoidable things have happened, with small rock fragments, micrometeorites colliding with one of Webb’s mirror segments.

But don’t panic. The engineers who made the telescopes are very aware of the rigors of the universe, and Webb is carefully designed to withstand them.

“Webb has always known that it needs to survive the space environment, including the harsh UV rays and charged particles from the Sun, cosmic rays from exotic light sources in the galaxy, and occasional attacks by micrometeoroids in the solar system. “Engineers and engineers say. Paul Geithner, Deputy Project Manager, Goddard Space Flight Center, NASA

“We designed and built a Webb with optical, thermal, electrical, and mechanical performance margins to ensure that we could carry out many years of ambitious scientific missions in outer space.”

webb l2The location of Webb in L2. (NASA)

Webb occupies an area called L2, which is 1.5 million kilometers (a little less than 1 million miles) from the earth.

This is known as the Lagrange point or Lagrange point, where the gravitational interaction between two orbiting objects (in this case the Earth and the Sun) balances the centripetal force of the orbit, allowing low-mass objects to exist. Create a stable pocket. “Parking” to reduce fuel consumption.

This is very useful for science, but these areas can also collect others.

For example, Jupiter has a group of asteroids that share an orbit at two Lagrange points that share the Sun. Other planets also have asteroids at the Lagrange point, though less than Jupiter.

I don’t know exactly how much dust the L2 collected, but it’s foolish to expect that the area didn’t collect it at all.

That’s why Webb was specially designed to withstand the impact of dust-sized particles that move at very high speeds. Not only did Webb’s design include simulations, engineers sought to influence the test on the mirror samples to understand and mitigate the effects of the space environment.

Impacts can move the mirror segment, but the telescope has a sensor that measures the position of the mirror and the ability to adjust the position of the mirror to help correct any possible distortions. ..

Here on Earth, Mission Control can also send adjustments to the Webb to return the mirror to where it should be. Its optics can even be kept away from previously known meteor showers.

Also, because Webb is built with significant margins of error, the expected physical degradation over time does not result in premature termination of the mission.

The influence of HubbleSpace debris affects damage to the Hubble Panels returned to Earth after a service mission. (NASA)

It could be in a better position than Hubble, which has been exposed to the constant bombing of space debris, as well as the impact of micrometeorites in low earth orbit.

However, unlike Hubble, the distance to the Webb means that the technician cannot physically visit and repair. (Hubble hasn’t been put in place recently. Such a last mission was in 2009 and you won’t receive another mission.)

The micrometeorites that hit the telescope between May 23 and 25 were random events. However, the impact was greater than expected, giving us an opportunity to better understand the L2 environment and seek strategies to protect our telescopes in the future.

“Because Webb’s mirrors are exposed in space, it was expected that micrometeoroid collisions would gracefully degrade the telescope’s performance over time,” said Lee Feinberg, NASA Goddard’s Webb Optical Telescope Element Manager. I am saying.

“Since the launch, we have experienced four small measurable micrometeorite strikes that are in line with expectations, which are larger than our expected degradation predictions these days.

“We use this flight data to update our performance analysis over time and develop operational approaches to ensure that Webb’s imaging performance is maximized as much as possible over the years to come. “

The first full-color and spectroscopic images from Webb will arrive on time on July 12, 2022. We can never wait.


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