NASA’s new SuperSpace Telescope suffered more damage than originally thought when it was hit by a space rock in May, a new report has revealed.
The observatory’s $10bn (£7.4bn) main mirror was permanently altered when it was hit by the single micrometeorite, NASA has revealed, although this will not affect Webb’s ability to take mesmerizing images as the first official published last week.
Analysis of the telescope during its commissioning phase revealed that five of the six micrometeor impacts on its large mirror between January and June caused minor damage.
However, a hit to a mirror segment designated C3 in mid-May left the telescope with more damage that can be fully repaired.
NASA’s new SuperSpace Telescope suffered more damage than first thought when it was hit by a space rock in May, a new report reveals
The observatory’s $10 billion ($7.4 billion) main mirror (pictured) was permanently altered when it was hit by the single micrometeorite, NASA has revealed, although this will not affect Webb’s ability to take mesmerizing images like the first official ones released last week
JAMES WEBB TELESCOPE INSTRUMENTS
NIRCam (Near Infrared Camera) infrared camera from the edge of the visible through the near infrared
NIRSpec (Near InfraRed Spectrograph) will also perform spectroscopy in the same wavelength range.
MIRI (Mid Infrared Instrument) will measure the mid to long infrared wavelength range from 5 to 27 micrometers.
The FGS/NIRISS (Fine-Targeting Sensor and Near-Infrared Imager and Slitless Spectrograph) is used to stabilize the observatory’s line-of-sight during science observations.
“The single micrometeorite impact that occurred between May 22 and 24, 2022 UT exceeded pre-launch damage expectations for a single micrometeorite, prompting further investigation and modeling by the JWST project,” the report said.
The commissioning period was a difficult process that began shortly after Webb reached space and continued until just a few weeks ago, when ground controllers successfully completed calibration, alignment and testing of the telescope’s mirrors and instruments.
During that time, five micrometeorite impacts caused little damage, amounting to less than 1 nanometer root mean square (RMS) wavefront error, which is a technical way of describing how much Webb’s mirror distorts the starlight that collects the mirror.
Most of the distortions added by these effects can be corrected by the mirror, as the 18 hexagonal segments that make it up can be individually and finely adjusted.
However, the sixth increased the segment wavefront error from 56 nanometers to 178 nanometers after correction by segment correction.
However, this damage to the C3 segment can still be compensated for and does not compromise the resolution of the Webb primary mirror as a whole.
The report adds: “The micrometeoroid that struck segment C3 in the period 22-24 May 2022 UT caused a significant uncorrectable change in the total number of this segment.
“However, the effect was small at the entire telescope level because only a small part of the telescope area was affected.”
Micrometeorite impacts are a problem for Webb because its 21-foot-diameter (6.5 m) mirror is exposed to space, unlike its predecessor, Hubble.
But because of its orbit 1 million miles (1.5 million kilometers) from Earth, at a point called the second Lagrange point, or L2, experts expected Webb to encounter potentially dangerous micrometeorites only about once a month.
Webb’s primary mirror consists of 18 hexagonal segments of gold-plated beryllium metal and is 21 feet 4 inches (6.5 meters) in diameter. It is supported by three shallow carbon fiber tubes or struts that extend from the main mirror
Webb’s infrared capabilities allow it to “see back in time” to the Big Bang, which occurred 13.8 billion years ago. Light waves travel extremely fast, about 186,000 miles (300,000 km) per second, every second. The further away an object is, the further back in time we are looking. This is due to the time it takes light to travel from the object to us
Spectacular: Pictured is the first image from the James Webb Space Telescope showing SMACS 0723, a galaxy cluster billions of light-years from Earth
“It is still unclear whether the May 2022 C3 segment impact was a rare event (ie, an unfortunate early impact by a high kinetic energy micrometeoroid that statistically can only happen once every few years),” it said. says in the report, “or whether the telescope might be more susceptible to damage by micrometeoroids than the pre-launch model predicted.
Webb’s team is now looking at what can be done to mitigate future micrometeorite impacts, including potentially limiting how long the telescope is pointed in directions known to expose the mirror to a greater likelihood of these impacts.
Last week, Webb’s dazzling, unprecedented images of a ‘stellar nursery’, a dying star covered in dust and a ‘cosmic dance’ between a cluster of galaxies were revealed to the world for the first time.
It ended months of waiting and frantic anticipation as people around the world were treated to the first batch of a treasure trove of images that would culminate in the earliest glimpse of the dawn of the universe.
Webb’s infrared capabilities mean it can “see back in time” to within just 100-200 million years of the Big Bang, allowing it to take pictures of the first stars that shone in the universe more than 13.5 billion years ago .
His first images of nebulae, an exoplanet and galactic clusters caused huge celebration in the scientific world on a day hailed as “a great day for mankind”.
Researchers will soon begin to learn more about the masses, ages, histories and compositions of galaxies as Webb seeks to explore the earliest galaxies in the universe.
The paper is published on the academic preprint server arxiv.org.
JAMES WEBB’S TELESCOPE
The James Webb Telescope has been described as a “time machine” that could help unlock the secrets of our universe.
The telescope will be used to look back to the first galaxies born in the early universe more than 13.5 billion years ago and observe the sources of stars, exoplanets and even the moons and planets of our solar system.
The huge telescope, already worth more than $7 billion (£5 billion), is seen as the successor to the orbiting Hubble Space Telescope
The James Webb Telescope and most of its instruments have an operating temperature of approximately 40 Kelvin—about minus 387 Fahrenheit (minus 233 Celsius).
It is the largest and most powerful orbiting space telescope in the world, capable of peering back 100-200 million years after the Big Bang.
The orbiting infrared observatory is designed to be about 100 times more powerful than its predecessor, the Hubble Space Telescope.
NASA likes to think of James Webb as Hubble’s successor rather than a replacement, as the two will work in tandem for some time.
The Hubble Space Telescope was launched on April 24, 1990 by the space shuttle Discovery from the Kennedy Space Center in Florida.
It orbits the Earth at about 17,000 miles per hour (27,300 kilometers per hour) in a low-Earth orbit about 340 miles above sea level.
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