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  NASA James Webb Space Telescope (JWST) (Page 2)

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Author Topic:   NASA James Webb Space Telescope (JWST)
Robert Pearlman
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NASA release
First Look: NASA's James Webb Space Telescope Fully Stowed

NASA's James Webb Space Telescope has been successfully folded and stowed into the same configuration it will have when loaded onto an Ariane 5 rocket for launch next year.

Above: A first look at NASA's James Webb Space Telescope fully stowed into the same configuration it will have when loaded into an Ariane V rocket for launch. The image was taken from a webcam in the clean room at Northrop Grumman, in Redondo Beach, California. With staffing restrictions in place due to COVID-19, only essential staff are allowed in the clean room. (Northrop Grumman)

Webb is NASA's largest and most complex space science telescope ever built. Too big for any rocket available in its fully expanded form, the entire observatory was designed to fold in on itself to achieve a much smaller configuration. Once in space, the observatory will unfold and stretch itself out in a carefully practiced series of steps before beginning to make groundbreaking observations of the cosmos.

"The James Webb Space Telescope achieved another significant milestone with the entire observatory in its launch configuration for the first time, in preparation for environmental testing," said Bill Ochs, Webb project manager for NASA Goddard Space Flight Center in Greenbelt, Maryland. "I am very proud of the entire Northrop Grumman and NASA integration and test team. This accomplishment demonstrates the outstanding dedication and diligence of the team in such trying times due to COVID-19."

The testing team's charter is to make sure every piece of hardware and every piece of software that comprise Webb will work not only individually, but as a full observatory. Now that Webb is completely assembled, technicians and engineers have seized the unique opportunity to command the entire spacecraft and carry out the various stages of movement and deployment it will perform when in space. By folding and stowing the spacecraft into the same configuration when it launches from French Guiana, the engineering team can confidently move forward with final environmental testing (acoustics and vibration). After completing the series of tests, Webb will be deployed one last time on Earth for testing prior to preparing for launch.

"While operating under augmented personal safety measures because of the novel coronavirus (COVID-19), the project continues to make good progress and achieve significant milestones in preparation for upcoming environmental testing," said Gregory L. Robinson, the Webb program director at NASA Headquarters in Washington, D.C. "Team member safety continues to be our highest priority as the project takes precautions to protect Webb's hardware and continue with integration and testing. NASA will continually assess the project's schedule and adjust decisions as the situation evolves."

Robert Pearlman
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NASA release
Tower Extension Test a Success for NASA's James Webb Space Telescope

To test the James Webb Space Telescope's readiness for its journey in space, technicians successfully commanded it to deploy and extend a critical part of the observatory known as the Deployable Tower Assembly.

Above: Technicians inspect a critical part of the James Webb Space Telescope known as the Deployable Tower Assembly after fully extending it in the same maneuver it will perform in once in space. (Northrop Grumman)

The primary purpose of the deployable tower is to create a large gap between the upper part of the observatory that houses its iconic gold mirrors and scientific instruments, and the lower section known as the spacecraft bus which holds its comparatively warm electronics and propulsion systems. By creating a space between the two, it allows for Webb's active and passive cooling systems to bring its mirrors and sensors down to staggeringly cold temperatures required to perform optimal science.

Webb was designed to look for faint traces of infrared light, which is essentially heat energy. To detect the extremely faint heat signals of astronomical objects that are incredibly far away, the telescope itself has to be very cold and stable.

During the test, the tower was slowly extended 48 inches (1.2 meters) upward over the course of several hours, in the same maneuver it will perform once in space. Simulating the zero-gravity environment Webb will operate in, engineers employed an innovative series of pulleys, counterbalances and a special crane called a gravity-negation system that perfectly offloaded all of the effects of Earth's gravity on the observatory. Now that Webb is fully assembled, the difficulty of testing and properly simulating a zero-gravity environment has increased significantly.

"The Deployable Tower Assembly worked beautifully during the test," said Alphonso Stewart the Webb deployment systems lead for NASA's Goddard Space Flight Center in Greenbelt, Maryland. "It performed exactly as predicted, and from our expectations from previous tests before the full observatory was assembled. This was the first time that this part of Webb was tested in its flight-like configuration to the highest level of fidelity we possibly could. This test provides the opportunity to assess all interfaces and interactions between the instrument and bus sections of the observatory."

Above: Shown fully stowed, the James Webb Space Telescope's Deployable Tower Assembly that connects the upper and lower sections of the spacecraft will extend 48 inches (1.2 meters) after launch. (Northrop Grumman)

In addition to helping the observatory cool down, the Deployable Tower Assembly is also a big part of how Webb is able to pack into a much smaller size to fit inside an Ariane 5 rocket for launch. Webb is the largest space science observatory ever built, but to fit a telescope that big into a rocket, engineers had to design it to fold down into a much smaller configuration. Webb's Deployable Tower Assembly helps Webb to just barely fit inside a 17.8-foot (5.4-meter) payload fairing. Once in space, the tower will extend to give the rest of Webb's deployable parts, such as the sunshield and mirrors, the necessary amount of room needed to unpack and unfold into a fully functional infrared space observatory.

"We need to know that Webb will work the way we expect it to before we send it to space," said Stewart. "This is why we test, and when we do, we test as flight-like as possible. The way we send the commands to the spacecraft, the sequence, the individual sitting at the console, the communication that we use. We replicate all of these things to see if we are missing something, to see if there is something that needs to be changed, and to make sure that all of our planning to date has been correct."

Following augmented personal safety procedures due to COVID-19, the James Webb Space Telescope's Northrop Grumman team in California continued integration and testing work with significantly reduced on-site personnel and shifts. The NASA/Northrop Grumman team recently resumed near-full operations. NASA is evaluating potential impacts on the March 2021 launch date, and will continually assess the schedule and adjust decisions as the situation unfolds.

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NASA release
NASA Announces New James Webb Space Telescope Target Launch Date

NASA now is targeting Oct. 31, 2021, for the launch of the agency's James Webb Space Telescope from French Guiana, due to impacts from the ongoing coronavirus (COVID-19) pandemic, as well as technical challenges.

This decision is based on a recently completed schedule risk assessment of the remaining integration and test activities prior to launch. Previously, Webb was targeted to launch in March 2021.

"The perseverance and innovation of the entire Webb Telescope team has enabled us to work through challenging situations we could not have foreseen on our path to launch this unprecedented mission," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate at the agency's headquarters in Washington. "Webb is the world's most complex space observatory, and our top science priority, and we've worked hard to keep progress moving during the pandemic. The team continues to be focused on reaching milestones and arriving at the technical solutions that will see us through to this new launch date next year."

Testing of the observatory continues to go well at Northrop Grumman, the mission's main industry partner, in Redondo Beach, California, despite the challenges of the coronavirus pandemic. Prior to the pandemic's associated delays, the team made significant progress in achieving important milestones to prepare for launch in 2021.

As schedule margins grew tighter last fall, the agency planned to assess the progress of the project in April. This assessment was postponed due to the pandemic and was completed this week. The factors contributing to the decision to move the launch date include the impacts of augmented safety precautions, reduced on-site personnel, disruption to shift work, and other technical challenges. Webb will use existing program funding to stay within its $8.8 billion development cost cap.

"Based on current projections, the program expects to complete the remaining work within the new schedule without requiring additional funds," said Gregory Robinson, NASA Webb program director at the agency's headquarters. "Although efficiency has been affected and there are challenges ahead, we have retired significant risk through the achievements and good schedule performance over the past year. After resuming full operations to prepare for upcoming final observatory system-level environmental testing this summer, major progress continues towards preparing this highly complex observatory for launch."

The project team will continue to complete a final set of extremely difficult environmental tests of the full observatory before it will be shipped to the launch site in Kourou, French Guiana, situated on the northeastern coast of South America.

This week, the project successfully completed electrical testing of the observatory. The test highlighted a major milestone in preparation for the upcoming acoustics and vibration environmental tests of the full observatory that are scheduled to start in August. In addition to ongoing deployments, ground system testing of the fully integrated observatory has followed immediately afterwards. Ensuring that every element of Webb functions properly before it gets to space is critical to its success.

The design of a very large space telescope and highly sophisticated instruments was required to enable Webb to answer fundamental questions about our cosmic origins outlined in the National Academy of Sciences 2000 Decadal Survey.

"Webb is designed to build upon the incredible legacies of the Hubble and Spitzer space telescopes, by observing the infrared universe and exploring every phase of cosmic history," said Eric Smith, NASA Webb's program scientist at the agency's headquarters. "The observatory will detect light from the first generation of galaxies that formed in the early universe after the big bang and study the atmospheres of nearby exoplanets for possible signs of habitability."

Early next year, Webb will be will folded "origami-style" for shipment to the launch site and fitted compactly inside Arianespace's Ariane 5 launch vehicle fairing, which is about 16 feet (5 meters) wide. On its journey to space, Webb will be the first mission to complete an intricate and technically challenging series of deployments – a critical part of Webb's journey to its orbit about one million miles from Earth. Once in orbit, Webb will unfold its delicate five-layered sunshield until it reaches the size of a tennis court. Webb will then deploy its iconic 6.5-meter primary mirror that will detect the faint light of far-away stars and galaxies.

Webb is NASA's next great space science observatory, which will help in solving the mysteries of our solar system, looking beyond to distant worlds around other stars, and probing the mystifying structures and origins of our universe. Webb is an international program led by NASA, along with its partners ESA (European Space Agency) and the Canadian Space Agency.

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Northrop Grumman release
Northrop Grumman and NASA Complete Environmental Testing on the James Webb Space Telescope

Northrop Grumman Corporation and NASA have completed environmental testing on the James Webb Space Telescope.

Above: For the first time ever, testing teams at Northrop Grumman in Redondo Beach, California carefully lifted the fully assembled James Webb Space Telescope in order to prepare it for transport to nearby acoustic and sine-vibration testing facilities. (NASA/Chris Gunn)

The environmental testing demonstrated Webb's ability to withstand harsh environmental characteristics during its upcoming rocket launch and journey to reach its orbit at the second Sun-Earth Lagrange point (L2), approximately one million miles away from Earth.

"The completion of environmental testing is a major step forward in our preparations for Webb's historic launch and a testament to the remarkable dedication of the team," said Scott Willoughby, vice president and program manager, James Webb Space Telescope, Northrop Grumman.

Webb's environmental testing consisted of a series of rigorous acoustic and sine-vibration tests spanning several weeks. Webb was first placed in Northrop Grumman's acoustic testing chamber where it underwent high frequency oscillating sound pressure levels above 140 decibels to simulate the effects of being launched on a rocket. The completion of the acoustic tests and analysis validated that Webb's hardware, science instruments, structure and electronics can successfully survive the planned rocket launch in a simulated environment.

Following the completion of acoustic testing, Webb transitioned to a separate chamber where it underwent a series of sine-vibration tests on a shaker table to simulate vertical and horizontal accelerations in lower frequencies. The observatory was rigorously exposed to vibration levels on the shaker that are well above the flight environment, exciting its resonances to demonstrate its capability to withstand the flight environment with significant margins.

The next series of major milestones for Webb will require NASA and Northrop Grumman engineers and technicians to deploy the observatory's five-layered sunshield followed by wing deployments of its primary mirror in order to fully verify Webb's flight worthiness. Lastly, Webb will undergo a full systems evaluation before it begins preparations for its historic journey to Kourou, French Guiana for its October 2021 launch.

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NASA release
NASA's Webb Sunshield Successfully Unfolds and Tensions in Final Tests

Lengthened to the size of a tennis court, the five-layer sunshield of NASA's fully assembled James Webb Space Telescope successfully completed a final series of large-scale deployment and tensioning tests. This milestone puts the observatory one step closer to its launch in 2021.

Above: The James Webb Space Telescope's final tests are underway with the successful completion of its last sunshield deployment test, which occurred at Northrop Grumman in Redondo Beach, California. (NASA/Chris Gunn)

"This is one of Webb's biggest accomplishments in 2020," said Alphonso Stewart, Webb deployment systems lead for NASA's Goddard Space Flight Center in Greenbelt, Maryland. "We were able to precisely synchronize the unfolding motion in a very slow and controlled fashion and maintain its critical kite-like shape, signifying it is ready to perform these actions in space."

The sunshield protects the telescope and reflects light and background heat from the Sun, Earth and Moon into space. The observatory must be kept cold to accomplish groundbreaking science in infrared light, which is invisible to human eyes and felt as heat.

In the sunshield's shadow, Webb's innovative technologies and sensitive infrared sensors will allow scientists to observe distant galaxies and study many other intriguing objects in the universe.

Maintaining the sunshield's shape involves a delicate, complicated process.

Above: To help ensure success, technicians carefully inspect the James Webb Space Telescope's sunshield before deployment testing begins, while it is occurring, and perform a full post-test analysis to ensure the observatory is operating as planned. (NASA/Chris Gunn)

"Congratulations to the entire team. Due to Webb's large size and stringent performance requirements, the deployments are incredibly complex. In addition to the required technical expertise, this set of tests required detailed planning, determination, patience and open communication. The team proved that it has all these attributes. It's amazing to think that next time Webb's sunshield is deployed it will be many thousands of miles away, hurtling through space," said James Cooper, Webb's sunshield manager at Goddard.

The Kapton® polymer-coated membranes of Webb's sunshield were fully deployed and tensioned in December at Northrop Grumman in Redondo Beach, California. Northrop Grumman designed the observatory's sunshield for NASA.

During testing, engineers sent a series of commands to spacecraft hardware that activated 139 actuators, eight motors, and thousands of other components to unfold and stretch the five membranes of the sunshield into its final taut shape. A challenging part of the test is to unfold the sunshield in Earth's gravity environment, which causes friction, unlike unfolding material in space without the effects of gravity.

For launch the sunshield will be folded up around two sides of the observatory and placed in an Ariane 5 launch vehicle, which is provided by the European Space Agency.

Above: Shown fully deployed with all five of its layers tensioned, this is the last time the James Webb Space Telescope's sunshield will be completely unfurled on Earth. (NASA/Chris Gunn)

In this test, two pallet structures that hold the sunshield upright folded down, then two huge "arms" (known as the Mid-Boom Assembly) of the sunshield slowly telescoped outward, pulling the folded membranes along with them to resemble the synchronized movements of a very slowly choreographed dance. Once the arms locked in their horizontal position, the membranes of the sunshield were successfully tensioned individually starting with the bottom layer, separating each into their fully deployed shape.

The large sunshield divides the observatory into a warm, Sun-facing side (about 185 degrees Fahrenheit) and a cold-space-facing side (minus 388 degrees Fahrenheit) comprised of the optics and scientific instruments. The sunshield will protect the observatory's optics and sensors, so they remain at extremely cold temperatures to conduct science.

"This milestone signals that Webb is well on its way to being ready for launch. Our engineers and technicians achieved incredible testing progress this month, reducing significant risk to the project by completing these milestones for launch next year," said Bill Ochs, project manager for Webb at Goddard. "The team is now preparing for final post-environmental deployment testing on the observatory these next couple of months prior to shipping to the launch site next summer."

Webb has passed other rigorous deployment tests during its development, which successfully uncovered and resolved technical issues with the spacecraft. These tests validate that once in orbit, the observatory and its many redundant systems will function flawlessly.

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NASA release
NASA's James Webb Space Telescope Completes Final Functional Tests to Prepare for Launch

February marked significant progress for NASA's James Webb Space Telescope, which completed its final functional performance tests at Northrop Grumman in Redondo Beach, California. Testing teams successfully completed two important milestones that confirmed the observatory's internal electronics are all functioning as intended, and that the spacecraft and its four scientific instruments can send and receive data properly through the same network they will use in space. These milestones move Webb closer to being ready to launch in October.

Above: Following the conclusion of the James Webb Space Telescope's recent milestone tests, engineering teams have confirmed that the observatory will both mechanically, and electronically survive the rigors anticipated during launch. (NASA/Chris Gunn)

These tests are known as the comprehensive systems test, which took place at Northrop Grumman, and the ground segment test, which took place in collaboration with the Space Telescope Science Institute in Baltimore.

Before the launch environment test, technicians ran a full scan known as a comprehensive systems test. This assessment established a baseline of electrical functional performance for the entire observatory, and all of the many components that work together to comprise the world's premiere space science telescope. Once environmental testing concluded, technicians and engineers moved forward to run another comprehensive systems test and compared the data between the two. After thoroughly examining the data, the team confirmed that the observatory will both mechanically and electronically survive the rigors of launch.

Above: During its final full systems test, technicians powered on all of the James Webb Space Telescope's various electrical components installed on the observatory, and cycled through their planned operations to ensure each was functioning, and communicating with each other. (NASA/Chris Gunn)

Through the course of 17 consecutive days of systems testing, technicians powered on all of Webb's various electrical components and cycled through their planned operations to ensure each was functioning and communicating with each other. All electrical boxes inside the telescope have an "A" and "B" side, which allows redundancy in flight and added flexibility. During the test all commands were input correctly, all telemetry received was correct and all electrical boxes, and each backup side functioned as designed.

"It's been amazing to witness the level of expertise, commitment and collaboration across the team during this important milestone," said Jennifer Love-Pruitt, Northrop Grumman's electrical vehicle engineering lead on the Webb observatory. "It's definitely a proud moment because we demonstrated Webb's electrical readiness. The successful completion of this test also means we are ready to move forward toward launch and on-orbit operations."

Webb's recent systems scan confirms the observatory will withstand the launch environment.

Following the completion of Webb's final comprehensive systems evaluation, technicians immediately began preparations for its next big milestone, known as a ground segment test. This test was designed to simulate the complete process from planning science observations to posting the scientific data to the community archive.

Webb's final ground segment test began by first creating a simulated plan that each of its scientific instruments would follow. Commands to sequentially turn on, move, and operate each of four scientific instruments were then relayed from Webb's Mission Operations Center (MOC) at the Space Telescope Science Institute (STScI) in Baltimore. During the test, the observatory is treated as if it were a million miles away in orbit. To do this, the Flight Operations Team connected the spacecraft to the Deep Space Network, an international array of giant radio antennas that NASA uses to communicate with many spacecraft. However, since Webb isn't in space yet, special equipment was used to emulate the real radio link that will exist between Webb and the Deep Space Network when Webb is in orbit. Commands were then relayed through the Deep Space Network emulator to the observatory at Northrop Grumman.

One of the unique aspects of Webb's final ground segment test occurred during a simulated flight environment when the team successfully practiced seamlessly switching over control from its primary MOC at STScI in Baltimore to the backup MOC at NASA's Goddard Space Flight Center in Greenbelt, Maryland. This demonstrated a backup plan that isn't anticipated to be needed but is necessary to practice and perfect prior to launch. Additionally, team members successfully sent multiple software patches to the observatory while it was performing its commanded operations.

"Working in a pandemic environment, of course, is a challenge, and our team has been doing an excellent job working through its nuances. That's a real positive to highlight, and it's not just for this test but all of the tests we've safely completed leading up to this one," said Bonnie Seaton, deputy ground segment & operations manager at Goddard. "This recent success is attributable to many months of preparation, the maturity of our systems, procedures, and products and the proficiency of our team."

When Webb is in space, commands will flow from STScI to one of the three Deep Space Network locations: Goldstone, California; Madrid, Spain; or Canberra, Australia. Signals will then be sent to the orbiting observatory nearly one million miles away. Additionally, NASA's Tracking and Data Relay Satellite network – the Space Network in New Mexico, the European Space Agency's Malindi station in Kenya, and European Space Operations Centre in Germany – will help keep a constant line of communication open with Webb.

Engineers and technicians continue to follow personal safety procedures in accordance with current CDC and Occupational Safety and Health Administration guidance related to COVID-19, including mask wearing and social distancing. The team is now preparing for the next series of technical milestones, which will include the final folding of the sunshield and deployment of the mirror, prior to shipment to the launch site.

The next series of milestones for Webb include a final sunshield fold and a final mirror deployment.

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NASA release
Webb's Golden Mirror Wings Open One Last Time on Earth

For the last time while it is on Earth, the world's largest and most powerful space science telescope opened its iconic primary mirror. This event marked a key milestone in preparing the observatory for launch later this year.

Above: The conclusion of this test represents the team's final in a long series of checkpoints designed to ensure Webb's 18 hexagonal mirrors are prepared for a long life of profound discovery. (NASA/Chris Gunn)

As part of the NASA's James Webb Space Telescope's final tests, the 6.5 meter (21 feet 4 inch) mirror was commanded to fully expand and lock itself into place, just like it would in space. The conclusion of this test represents the team's final checkpoint in a long series of tests designed to ensure Webb's 18 hexagonal mirrors are prepared for a long journey in space, and a life of profound discovery. After this, all of Webb's many movable parts will have confirmed in testing that they can perform their intended operations after being exposed to the expected launch environment.

"The primary mirror is a technological marvel. The lightweight mirrors, coatings, actuators and mechanisms, electronics and thermal blankets when fully deployed form a single precise mirror that is truly remarkable," said Lee Feinberg, optical telescope element manager for Webb at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "This is not just the final deployment test sequence that the team has pulled off to prepare Webb for a life in space, but it means when we finish, that the primary mirror will be locked in place for launch. It's humbling to think about the hundreds of dedicated people across the entire country who worked so hard to design and build the primary mirror, and now to know launch is so close."

Making the testing conditions close to what Webb will experience in space helps to ensure the observatory is fully prepared for its science mission one million miles away from Earth.

Commands to unlatch and deploy the side panels of the mirror were relayed from Webb's testing control room at Northrop Grumman, in Redondo Beach, California. The software instructions sent, and the mechanisms that operated are the same as those used in space. Special gravity offsetting equipment was attached to Webb to simulate the zero-gravity environment in which its complex mechanisms will operate. All of the final thermal blanketing and innovative shielding designed to protect its mirrors and instruments from interference were in place during testing.

To observe objects in the distant cosmos, and to do science that's never been done before, Webb's mirror needs to be so large that it cannot fit inside any rocket available in its fully extended form. Like a piece of origami artwork, Webb contains many movable parts that have been specifically designed to fold themselves to a compact formation that is considerably smaller than when the observatory is fully deployed. This allows it to just barely fit inside a 16-foot (5-meter) rocket fairing, with little room to spare.

To deploy, operate and bring its golden mirrors into focus requires 132 individual actuators and motors in addition to complex backend software to support it. A proper deployment in space is critically important to the process of fine-tuning Webb's individual mirrors into one functional and massive reflector. Once the wings are fully extended and in place, extremely precise actuators on the backside of the mirrors position and bend or flex each mirror into a specific prescription. Testing of each actuator and their expected movements was completed in a final functional test earlier this year.

"Pioneering space observatories like Webb only come to fruition when dedicated individuals work together to surmount the challenge of building something that has never been done before. I am especially proud of our teams that built Webb's mirrors, and the complex back-end electronics and software that will empower it to see deep into space with extreme precision. It has been very interesting, and extremely rewarding to see it all come together. The completion of this last test on its mirrors is especially exciting because of how close we are to launch later this year," said Ritva Keski-Kuha, deputy optical telescope element manager for Webb at Goddard.

Following this test engineers will immediately move on to tackle Webb's final few tests, which include extending and then restowing two radiator assemblies that help the observatory cool down, and one full extension and restowing of its deployable tower.

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NASA release
NASA's James Webb Space Telescope Has Completed Testing

After successful completion of its final tests, NASA's James Webb Space Telescope is being prepped for shipment to its launch site.

Above: Fully assembled and fully tested, NASA's James Webb Space Telescope has completed its primary testing regimen and will soon begin shipment preparations. (NASA/Chris Gunn)

Engineering teams have completed Webb's long-spanning comprehensive testing regimen at Northrop Grumman's facilities. Webb's many tests and checkpoints were designed to ensure that the world's most complex space science observatory will operate as designed once in space.

Fully assembled and fully tested, NASA's James Webb Space Telescope has completed its primary testing regimen and will soon begin shipment preparations.

Now that observatory testing has concluded, shipment operations have begun. This includes all the necessary steps to prepare Webb for a safe journey through the Panama Canal to its launch location in Kourou, French Guiana, on the northeastern coast of South America. Since no more large-scale testing is required, Webb's clean room technicians have shifted their focus from demonstrating it can survive the harsh conditions of launch and work in orbit, to making sure it will safely arrive at the launch pad. Webb's contamination control technicians, transport engineers, and logistics task forces are all expertly prepared to handle the unique task of getting Webb to the launch site. Shipping preparations will be completed in September.

Webb Will Soon Be on its Way

"NASA's James Webb Space Telescope has reached a major turning point on its path toward launch with the completion of final observatory integration and testing," said Gregory L. Robinson, Webb's program director at NASA Headquarters in Washington. "We have a tremendously dedicated workforce who brought us to the finish line, and we are very excited to see that Webb is ready for launch and will soon be on that science journey."

Above: With integration and testing formally concluded for the James Webb Space Telescope, NASA's next giant leap into the cosmic unknown will soon be underway. (NASA/Chris Gunn)

While shipment operations are underway, teams located in Webb's Mission Operations Center (MOC) at the Space Telescope Science Institute (STScI) in Baltimore will continue to check and recheck the complex communications network it will use in space. Recently this network fully demonstrated that it is capable of seamlessly sending commands to the spacecraft. Live launch rehearsals are underway within the MOC with the explicit purpose of preparing for launch day and beyond. There is much to be done before launch, but with integration and testing formally concluded, NASA's next giant leap into the cosmic unknown will soon be underway.

Once Webb arrives in French Guiana, launch processing teams will configure the observatory for flight. This involves post-shipment checkouts to ensure the observatory hasn't been damaged during transport, carefully loading the spacecraft's propellant tanks with hydrazine fuel and nitrogen tetroxide oxidizer it will need to power its rocket thrusters to maintain its orbit, and detaching 'remove before flight' red-tag items like protective covers that keep important components safe during assembly, testing, and transport. Then engineering teams will mate the observatory to its launch vehicle, an Ariane 5 rocket provided by ESA (European Space Agency), before it rolls out to the launch pad. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

The James Webb Space Telescope is an amazing feat of human ingenuity, made more impressive by the obstacles Webb personnel overcame to deliver this amazing space science observatory. Earthquakes, a devastating hurricane, snowstorms, blizzards, wildfires, and a global pandemic are only some of what the people behind Webb endured to ensure success. Webb's story is one of perseverance – a mission with contributions from thousands of scientists, engineers, and other professionals from more than 14 countries and 29 states, in nine different time zones.

"To me, launching Webb will be a significant life event – I'll be elated of course when this is successful, but it will also be a time of deep personal introspection. Twenty years of my life will all come down to that moment," said Mark Voyton, Webb observatory integration and test manager at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "We've come a long way and worked through so much together to prepare our observatory for flight. The telescope's journey is only just beginning, but for those of us on the ground who built it, our time will soon come to an end, and we will have our opportunity to rest, knowing we put everything on the line to make sure our observatory works. The bonds we formed with each other along the way will last far into the future."

Opening NASA's New Eye on the Cosmos

After launch, Webb will undergo an action-packed six-month commissioning period. Moments after completing a 26-minute ride aboard the Ariane 5 launch vehicle, the spacecraft will separate from the rocket and its solar array will deploy automatically. After that, all subsequent deployments over the next few weeks will be initiated from ground control located at STScI.

Webb will take one month to fly to its intended orbital location in space nearly one million miles away from Earth, slowly unfolding as it goes. Sunshield deployments will begin a few days after launch, and each step can be controlled expertly from the ground, giving Webb's launch full control to circumnavigate any unforeseen issues with deployment.

Once the sunshield starts to deploy, the telescope and instruments will enter shade and start to cool over time. Over the ensuing weeks, the mission team will closely monitor the observatory's cooldown, managing it with heaters to control stresses on instruments and structures. In the meantime, the secondary mirror tripod will unfold, the primary mirror will unfold, Webb's instruments will slowly power up, and thruster firings will insert the observatory into a prescribed orbit.

Once the observatory has cooled down and stabilized at its frigid operating temperature, several months of alignments to its optics and calibrations of its scientific instruments will occur. Scientific operations are expected to commence approximately six months after launch.

'Flagship' missions like Webb are generational projects. Webb was built on both the legacy and the lessons of missions before it, such as the Hubble and Spitzer space telescopes, and it will in turn provide the foundation upon which future large astronomical space observatories may one day be developed.

"After completing the final steps of the James Webb Space Telescope's testing regimen, I can't help but see the reflections of the thousands of individuals who have dedicated so much of their lives to Webb, every time I look at that beautiful gold mirror," said Bill Ochs, Webb project manager for NASA Goddard.

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NASA release
NASA Readies James Webb Space Telescope for December Launch

NASA plans to launch the James Webb Space Telescope into orbit Dec. 18, 2021, to serve as the premier deep space observatory for the next decade.

The agency set the new target launch date in coordination with Arianespace after Webb recently and successfully completed its rigorous testing regimen – a major turning point for the mission. The new date also follows Arianespace successfully launching an Ariane 5 rocket in late July and scheduling a launch that will precede Webb. The July launch was the first for an Ariane 5 since August 2020.

Webb, an international program led by NASA with its partners ESA (European Space Agency) and the Canadian Space Agency, will launch on an Ariane 5 from Europe's Spaceport in French Guiana on the northeastern coast of South America. ESA is providing the Ariane 5.

The highly complex space telescope is currently resting in its final stow configuration at Northrop Grumman's facilities in Redondo Beach, California.

"Webb is an exemplary mission that signifies the epitome of perseverance," said Gregory L. Robinson, Webb's program director at NASA Headquarters in Washington. "I am inspired by our dedicated team and our global partnerships that have made this incredible endeavor possible. Together, we've overcome technical obstacles along the way as well as challenges during the coronavirus pandemic. I also am grateful for the steadfast support of Congress. Now that we have an observatory and a rocket ready for launch, I am looking forward to the big day and the amazing science to come."

The Webb team is preparing for shipment operations, during which the observatory will undergo final closeout procedures and packing for its journey to the launch site. The major elements of the Ariane 5 rocket that will carry Webb into space have safely arrived in Kourou, French Guiana, from Europe.

The Webb telescope's revolutionary technology will explore every phase of cosmic history – from within our solar system to the most distant observable galaxies in the early universe, and everything in between. Webb will reveal new and unexpected discoveries, and help humankind understand the origins of the universe and our place in it.

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NASA release
NASA's Webb Space Telescope Arrives in French Guiana After Sea Voyage

NASA's James Webb Space Telescope successfully arrived in French Guiana Tuesday, after a 16-day journey at sea. The 1,500-mile voyage took Webb from California through the Panama Canal to Port de Pariacabo on the Kourou River in French Guiana, on the northeastern coast of South America.

Above: After the custom-built shipping container carrying Webb is unloaded from the MN Colibri, Webb will be transported to its launch site, Europe's Spaceport in Kourou, French Guiana. (NASA/Chris Gunn)

The world's largest and most complex space science observatory will now be driven to its launch site, Europe's Spaceport in Kourou, where it will begin two months of operational preparations before its launch on an Ariane 5 rocket, scheduled for Dec. 18.

Once operational, Webb will reveal insights about all phases of cosmic history – back to just after the big bang – and will help search for signs of potential habitability among the thousands of exoplanets scientists have discovered in recent years. The mission is an international collaboration led by NASA, in partnership with the European and Canadian space agencies.

"The James Webb Space Telescope is a colossal achievement, built to transform our view of the universe and deliver amazing science," said NASA Administrator Bill Nelson. "Webb will look back over 13 billion years to the light created just after the big bang, with the power to show humanity the farthest reaches of space that we have ever seen. We are now very close to unlocking mysteries of the cosmos, thanks to the skills and expertise of our phenomenal team."

After completing testing in August at Northrop Grumman's Space Park in Redondo Beach, California, the Webb team spent nearly a month folding, stowing, and preparing the massive observatory for shipment to South America. Webb was shipped in a custom-built, environmentally controlled container.

Late in the evening of Friday, Sept. 24, Webb traveled with a police escort 26 miles through the streets of Los Angeles, from Northrop Grumman's facility in Redondo Beach to Naval Weapons Station Seal Beach. There, it was loaded onto the MN Colibri, a French-flagged cargo ship that has previously transported satellites and spaceflight hardware to Kourou. The MN Colibri departed Seal Beach Sunday, Sept. 26 and entered the Panama Canal Tuesday, Oct. 5 on its way to Kourou.

Above: The MN Colibri arrived Oct. 12 at Port de Pariacabo on the Kourou River in French Guiana, carrying NASA's James Webb Space Telescope as cargo. (NASA/Chris Gunn)

The ocean journey represented the final leg of Webb's long, earthbound travels over the years. The telescope was assembled at NASA's Goddard Space Flight Center in Greenbelt, Maryland, starting in 2013. In 2017, it was shipped to NASA's Johnson Space Center in Houston for cryogenic testing at the historic "Chamber A" test facility, famous for its use during the Apollo missions. In 2018, Webb shipped to Space Park in California, where for three years it underwent rigorous testing to ensure its readiness for operations in the environment of space.

"A talented team across America, Canada, and Europe worked together to build this highly complex observatory. It's an incredible challenge – and very much worthwhile. We are going to see things in the universe beyond what we can even imagine today," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate in Washington. "Now that Webb has arrived in Kourou, we're getting it ready for launch in December – and then we will watch in suspense over the next few weeks and months as we launch and ready the largest space telescope ever built."

After Webb is removed from its shipping container, engineers will run final checks on the observatory's condition. Webb will then be configured for flight, which includes loading the spacecraft with propellants, before Webb is mounted on top of the rocket and enclosed in the fairing for launch.

"Webb's arrival at the launch site is a momentous occasion," said Gregory Robinson, Webb's program director at NASA Headquarters. "We are very excited to finally send the world's next great observatory into deep space. Webb has crossed the country and traveled by sea. Now it will take its ultimate journey by rocket one million miles from Earth, to capture stunning images of the first galaxies in the early universe that are certain to transform our understanding of our place in the cosmos."

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NASA release
NASA Provides Update on Webb Telescope Launch

The launch readiness date for the James Webb Space Telescope is moving to no earlier than Dec. 22 to allow for additional testing of the observatory, following a recent incident that occurred during Webb's launch preparations.

The incident occurred during operations at the satellite preparation facility in Kourou, French Guiana, performed under Arianespace overall responsibility. Technicians were preparing to attach Webb to the launch vehicle adapter, which is used to integrate the observatory with the upper stage of the Ariane 5 rocket. A sudden, unplanned release of a clamp band – which secures Webb to the launch vehicle adapter – caused a vibration throughout the observatory.

A NASA-led anomaly review board was immediately convened to investigate and instituted additional testing to determine with certainty the incident did not damage any components. NASA and its mission partners will provide an update when the testing is completed at the end of this week.

Webb was previously scheduled to launch Dec. 18 on an Arianespace Ariane 5 rocket from Kourou.

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NASA update
Testing Confirms Webb Telescope on Track for Targeted Launch

Engineering teams have completed additional testing confirming NASA's James Webb Space Telescope is ready for flight, and launch preparations are resuming toward Webb's target launch date of Wednesday, Dec. 22, at 7:20 a.m. EST.

Additional testing was conducted this week to ensure the observatory's health following an incident that occurred when the release of a clamp band caused a vibration throughout the observatory.

On Wednesday, Nov. 24, engineering teams completed these tests, and a NASA-led anomaly review board concluded no observatory components were damaged in the incident. A "consent to fuel" review was held, and NASA gave approval to begin fueling the observatory. Fueling operations will begin Thursday, Nov. 25, and will take about 10 days.

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NASA release (photos credit: ESA/M. Pedoussaut)
Webb Placed on Top of Ariane 5

On Saturday, Dec. 11, NASA's James Webb Space Telescope was secured on top of the Ariane 5 rocket that will launch it to space from Europe's Spaceport in French Guiana.

After its arrival in the final assembly building, Webb was slowly hoisted nearly 130 feet and then perfectly aligned on top of the Ariane 5, after which technicians bolted Webb's launch vehicle adapter down to the rocket.

This whole process was performed under strict safety and cleanliness policies, as it was one of the most delicate operations during the entire launch campaign for Webb. A custom 'shower curtain,' already installed between the two platforms where technicians worked to connect Webb to its launch vehicle, served as the walls of a clean room to keep the observatory dirt-free.

The next step ahead is to encapsulate Webb inside the Ariane 5's specially adapted fairing.

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NASA update
Webb Space Telescope launch delayed

The James Webb Space Telescope team is working a communication issue between the observatory and the launch vehicle system. This will delay the launch date to no earlier than Friday, Dec. 24.

We will provide more information about the new launch date no later than Friday, Dec. 17.

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NASA release (photo credit: ESA/Manuel Pedoussaut)
NASA’s Webb Space Telescope Launch Confirmed for Dec. 24

The James Webb Space Telescope is confirmed for the target launch date of Dec. 24, 2021, at 7:20 a.m. EST (1220 GMT).

Late yesterday (Dec. 17), teams at the launch site successfully completed encapsulation of the observatory inside the Ariane 5 rocket that will launch it to space. Webb’s final launch readiness review will be held on Tuesday Dec. 21 and, if successful, roll-out is planned for Wednesday, Dec. 22.

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European Space Agency (ESA) release
Webb: new target launch date

Today, 21 December 2021, the Launch Readiness Review for flight VA256 to launch the James Webb Space Telescope has been successfully completed and concluded with the authorisation to perform the launch vehicle rollout and the start of the launch chronology.

However, due to adverse weather conditions at Europe’s Spaceport in French Guiana, flight VA256 – initially scheduled for 24 December – is being postponed.

The new targeted launch date is 25 December, as early as possible within the launch window 12:20–12:52 GMT / 13:20–13:52 CET [7:20-7:52 a.m. EST].

Tomorrow evening, local time in Kourou, another weather forecast will be issued in order to confirm the date of 25 December. The Ariane 5 launch vehicle and Webb are in stable and safe conditions in the final assembly building.

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Photos credit: NASA/Bill Ingalls
Ariane rocket with Webb Telescope rolled out to launch pad

The James Webb Space Telescope, mounted atop the Ariane 5 rocket it will ride into space, has arrived at its final location on Earth: the Arianespace ELA-3 launch complex at Europe’s Spaceport located near Kourou, French Guiana.

Webb is scheduled for liftoff at 7:20 a.m. EST on Saturday (Dec. 25).

With Webb and its rocket securely on the pad, the team will run electrical diagnostics to ensure all are configured for the launch. Teams will power on the observatory while at the launch pad to run one final aliveness test to ensure all systems are working before liftoff.

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collectSPACE
James Webb Space Telescope lifts off to reveal early galaxies, exoplanets

The world's largest and most powerful space telescope has made it safely off the planet, but it still has a complex deployment and a million-mile journey before it can start revealing the universe like never before.

The James Webb Space Telescope (JWST), named after the Apollo-era NASA administrator who championed space science, is an infrared observatory that will be used to image the earliest galaxies and to discern the atmospheric properties of exoplanets. It is intended as the scientific successor for the Hubble and Spitzer space telescopes, which remain in operation.

On Saturday (Dec. 25), an Ariane 5 rocket carrying the intricately-folded Webb lifted off from Arianespace's ELA-3 launch complex at Europe's Spaceport located near Kourou, French Guiana. The 7:20 a.m. EST (1220 GMT or 9:20 a.m. local time) launch began a 27-minute powered climb into space that culminated in the telescope separating from its rocket's upper stage and automatically deploying its solar array within a half hour of leaving Earth.

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NASA update
First mid-course correction burn complete

On Sunday (Dec. 25) at 7:50 p.m. EST (0050 GMT Dec. 26), the James Webb Space Telescope's first mid-course correction burn began. It lasted 65 minutes and is now complete. This burn is one of two milestones that are time critical — the first was the solar array deployment, which happened shortly after launch.

This burn adjusts Webb's trajectory toward the second Lagrange point, commonly known as L2. After launch, Webb needs to make its own mid-course thrust correction maneuvers to get to its orbit. This is by design: Webb received an intentional slight under-burn from the Ariane 5 that launched it into space, because it's not possible to correct for overthrust. If Webb gets too much thrust, it can't turn around to move back toward Earth because that would directly expose its telescope optics and structure to the Sun, overheating them and aborting the science mission before it can even begin.

Therefore, we ease up to the correct velocity in three stages, being careful never to deliver too much thrust — there will be three mid-course correction maneuvers in total.

After this burn, no key milestones are time critical, so the order, location, timing, and duration of deployments may change.

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NASA update
High-gain antenna released and tested

Shortly after 10 a.m. EST on Sunday (Dec. 26), the Webb team began the process of releasing the gimbaled antenna assembly, or GAA, which includes Webb's high-data-rate dish antenna. This antenna will be used to send at least 28.6 gigabytes of science data down from the observatory, twice a day.

The team has now released and tested the motion of the antenna assembly. The entire process took about one hour.

Separately, overnight, the temperature sensors and strain gauges on the telescope were activated for the first time. Temperature and strain data are now available to engineers monitoring Webb's thermal and structural systems.

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NASA update
Second course correction burn completed

On Monday (Dec. 27) at 7:20 p.m. EST – 60 hours after liftoff — Webb’s second mid-course correction burn began. It lasted 9 minutes and 27 seconds and is now complete.

This burn is the second of three planned course corrections to put the telescope precisely in orbit around the second Lagrange point, commonly known as L2.

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NASA update
Forward pallet structure lowered, beginning multiple-day sunshield deployment

Early this afternoon (Dec. 28) the Webb mission operations team concluded the deployment of the first of two structures that hold within them Webb's most unpredictable and in many ways complicated component: the sunshield.

The structures – called the Forward and Aft Unitized Pallet Structures – contain the five carefully folded sunshield membranes, plus the cables, pulleys, and release mechanisms that make up Webb's sunshield. The team completed the deployment of the forward pallet at approximately 1:21 p.m. EST, after beginning the entire process about four hours earlier. The team will now move on to the aft pallet deployment.

The deployment of the forward pallet required several hours of the mission operations team carefully walking through dozens of steps – only one of which was the actual motor-driven deployment to move the pallet from its stowed position to its deployed state. The lowering of the forward pallet also marks the first time that structure has conducted that movement since it underwent its final unfolding and deployment test at Northrop Grumman Space Park in Redondo Beach, California.

The deployment of the pallet structures begins what will be at least five more days of necessary steps to deploy the sunshield – a process that will ultimately determine the mission's ability to succeed. If the sunshield isn't in place to keep Webb's telescope and instruments extremely cold, Webb would be unable to observe the universe in the way it was designed.

The steps involved – outlined here – will continue after today with the extension of the Deployable Tower Assembly, followed by the release of the sunshield covers, the extension of the mid-booms, and finally the tensioning of the five Kapton layers of the sunshield itself.

As the deployment of the sunshield will be one of the most challenging spacecraft deployments NASA has ever attempted, the mission operations team built flexibility into the planned timeline, so that the schedule and even sequence of the next steps could change in the coming days.

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NASA update
Aft sunshield ballet deployed

Webb is beginning to resemble the form it will take when it is fully deployed – now that the mission operations team has successfully deployed and latched into place the observatory's forward and aft Unitized Pallet Structures.

The team began working through the deployment of the forward pallet this morning (Dec. 28), concluding at approximately 1:21 p.m. EST. The team then moved on to the aft pallet deployment, completing the process at approximately 7:27 p.m. EST.

While the actual motion to lower the forward pallet from its stowed to its deployed position took only 20 minutes, and the lowering of the aft pallet took only 18 minutes, the overall process took several hours for each because of the dozens of additional steps required. These include closely monitoring structural temperatures, maneuvering the observatory with respect to the sun to provide optimal temperatures, turning on heaters to warm key components, activating release mechanisms, configuring electronics and software, and ultimately latching the pallets into place.

The unfolding of the pallets marks the beginning of Webb's major structural deployments and also the beginning of the sunshield deployment phase – which will continue through at least this Sunday, Jan. 2.

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NASA update
Deployable tower assembly extended

This afternoon (Dec. 29), the Webb team successfully extended the observatory’s Deployable Tower Assembly (DTA), creating critical distance between the two halves of the spacecraft.

The DTA extended about 48 inches (1.22 meters), putting room between the upper section of the observatory, which houses the mirrors and scientific instruments, and the spacecraft bus, which holds the electronics and propulsion systems. This creates enough distance to allow the sensitive mirrors and instruments to cool down to the necessary temperatures to detect infrared light. This gap will also provide room for the sunshield membranes to fully unfold.

The deployment took more than six and a half hours, as engineers activated release devices and configured heaters, software, and electronics, before commanding the DTA itself to extend. The movement of the DTA, which looks like a large, black pipe, is driven by a motor. The team began the deployment at approximately 9:45 a.m. EST and completed it at approximately 4:24 p.m. EST.

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NASA update
Aft momentum flap deployed, sunshield covers released

Shortly after 9 a.m. EST today (Dec. 30), the Webb team completed deployment of the observatory's aft momentum flap. In a process that took about eight minutes, engineers released the flap's hold-down devices, and a spring brought the flap into its final position.

The aft momentum flap helps minimize the fuel engineers will need to use throughout Webb's lifetime, by helping to maintain the observatory's orientation in orbit. As photons of sunlight hit the large sunshield surface, they will exert pressure on the sunshield, and if not properly balanced, this solar pressure would cause rotations of the observatory that must be accommodated by its reaction wheels. The aft momentum flap will sail on the pressure of these photons, balancing the sunshield and keeping the observatory steady.

Just as a ship's mast must be set in position and the rigging established before the ship unfurls its sails, Webb's pallet structures, momentum flap, and mid-booms will soon all be in place for Webb's silver sunshield to unfold.

Webb's engineers then released and rolled up the sunshield covers that protected the thin layers of Webb's sunshield during launch. After the team electrically activated release devices to release the covers, they executed commands to roll the covers up into a holding position, exposing Webb's sunshield membranes to space for the first time.

The deployment, which took about an hour, concluded at approximately 12:27 p.m. EST.

In their next stages of planned activities, engineers will deploy the sunshield mid-booms, before proceeding with sunshield tensioning. The steps in this process, controlled by humans at Webb's Mission Operations Center, may change.

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NASA update
First of two sunshield mid-booms deploys

The Webb mission operations team has extended the first of the sunshield's two "arms" – the port (left side) mid-boom.

The critical step of the port mid-boom deployment was scheduled to begin earlier in the day (Dec. 31). However, the team paused work to confirm that the sunshield cover had fully rolled up as the final preparatory step before the mid-boom deployment.

Switches that should have indicated that the cover rolled up did not trigger when they were supposed to. However, secondary and tertiary sources offered confirmation that it had. Temperature data seemed to show that the sunshield cover unrolled to block sunlight from a sensor, and gyroscope sensors indicated motion consistent with the sunshield cover release devices being activated.

After analysis, mission management decided to move forward with the regularly planned deployment sequence. The deployment of the five telescoping segments of the motor-driven mid-boom began around 1:30 p.m. EST, and the arm extended smoothly until it reached full deployment at 4:49 p.m.

As Webb's deployment steps are all human-controlled, the schedule for deployments could continue to change – as today's activities showed. Shortly before 6:30 p.m., the team decided to proceed with deploying the starboard mid-boom tonight, and the initial steps of that deployment began just after 7 p.m.

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NASA update
Mid-booms extended, sunshield takes shape

With the successful extension of Webb's second sunshield mid-boom, the observatory has passed another critical deployment milestone. Webb's sunshield now resembles its full, kite-shaped form in space.

Engineers began to deploy the second (starboard) mid-boom on Friday (Dec. 31) at 6:31 p.m. EST and completed the process at about 10:13 p.m. EST.

The completion of the sunshield cover and mid-boom deployments over the past two days marks a critical milestone for Webb: all 107 membrane release devices associated with the sunshield deployment — every single one of which had to work in order for the sunshield to deploy — have now successfully released. Webb has 178 of these 'non-explosive actuators' in all; 107 were used to keep the sunshield safe and folded prior to deployment.

As the mid-booms slowly pushed out horizontally from the spacecraft, each driven by a motor, they pulled the folded membranes of the sunshield with them. This extended the sunshield to its full 47-foot width all the way across the observatory.

"The mid-booms are the sunshield's workhorse and do the heavy lifting to unfold and pull the membranes into that now-iconic shape," said Keith Parrish, Webb observatory manager at NASA's Goddard Space Flight Center.

While the deployments took longer than expected today, that was due to the operations team moving forward with caution and according to the protocols they laid out for dealing with unpredictable situations.

"Today is an example of why we continue to say that we don't think our deployment schedule might change, but that we expect it to change," Parrish said. "The team did what we had rehearsed for this kind of situation – stop, assess, and move forward methodically with a plan. We still have a long way to go with this whole deployment process."

The two mid-boom arms are now locked in their final position. They will hold the sunshield membranes in their proper place, as the team turns to the final stage in the sunshield's deployment: tensioning.

In the coming days, the team will separate and then individually tension each of the five sunshield layers, stretching them into their final, taut shape. This will create space between the membranes to allow heat to radiate out, making each successive layer of the sunshield cooler than the one below.

Webb's engineers will begin with the bottom layer – the largest and flattest layer, which is closest to the Sun and will reach the highest temperatures. They will proceed sequentially to the fifth and smallest layer, closest to the primary mirror. Tensioning the layers involves sending commands to activate several motors to reel in a total of 90 cables through numerous pulleys and cable management devices. Sunshield tensioning will take at least two days but may take longer, due to the complexity of the process and the flexibility built into the timeline.

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NASA update
Optimizing Webb's power systems

Taking advantage of its flexible commissioning schedule, the Webb team has decided to focus today on optimizing Webb's power systems while learning more about how the observatory behaves in space. As a result, the Webb mission operations team has moved the beginning of sunshield tensioning activities to no earlier than tomorrow, Monday, Jan. 3. This will ensure Webb is in prime condition to begin the next major deployment step in its unfolding process.

Specifically, the team is analyzing how the power subsystem is operating now that several of the major deployments have been completed. Simultaneously, the deployments team is working to make sure motors that are key to the tensioning process are at the optimal temperatures prior to beginning that operation.

Using an approach to keep mission operations focused on as few activities as necessary at a time, mission managers have chosen to wait to resume sunshield deployment steps after better understanding the details of how Webb is functioning in its new environment.

"Nothing we can learn from simulations on the ground is as good as analyzing the observatory when it's up and running," said Bill Ochs, Webb project manager, based at NASA's Goddard Space Flight Center. "Now is the time to take the opportunity to learn everything we can about its baseline operations. Then we will take the next steps."

Webb's deployment was designed so that the team could pause deployments if necessary. In this case, Ochs said, they are relying on that flexibility in order to properly address how the massive and complex observatory is responding to the environment of space.

"We've spent 20 years on the ground with Webb, designing, developing, and testing," said Mike Menzel, of NASA's Goddard Space Flight Center, Webb's lead systems engineer. "We've had a week to see how the observatory actually behaves in space. It's not uncommon to learn certain characteristics of your spacecraft once you're in flight. That's what we're doing right now. So far, the major deployments we've executed have gone about as smoothly as we could have hoped for. But we want to take our time and understand everything we can about the observatory before moving forward."

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NASA update
First layer of sunshield tightened

Today (Jan. 3), at 3:48 p.m. EST, the Webb team finished tensioning the first layer of the observatory’s sunshield — that is, tightening it into its final, completely taut position. This is the first of five layers that will each be tightened in turn over the next two to three days, until the observatory’s sunshield is fully deployed. The process began around 10 a.m. EST.

This layer is the largest of the five, and the one that will experience the brunt of the heat from the Sun. The tennis-court-sized sunshield helps keep the telescope cold enough to detect the infrared light it was built to observe.

The team has now begun tensioning the second layer.

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NASA update
Second and third layers of sunshield fully tightened

The Webb team has completed tensioning for the first three layers of the observatory's kite-shaped sunshield, 47 feet across and 70 feet long.

The first layer – pulled fully taut into its final configuration – was completed mid-afternoon.

The team began the second layer at 4:09 p.m. EST today (Jan. 3), and the process took 74 minutes. The third layer began at 5:48 p.m. EST, and the process took 71 minutes. In all, the tensioning process from the first steps this morning until the third layer achieved tension took just over five and a half hours.

These three layers are the ones closest to the Sun. Tensioning of the final two layers is planned for tomorrow.

"The membrane tensioning phase of sunshield deployment is especially challenging because there are complex interactions between the structures, the tensioning mechanisms, the cables and the membranes," said James Cooper, NASA's Webb sunshield manager, based at Goddard Space Flight Center. "This was the hardest part to test on the ground, so it feels awesome to have everything go so well today. The Northrop and NASA team is doing great work, and we look forward to tensioning the remaining layers."

Once fully deployed, the sunshield will protect the telescope from the Sun's radiation. It will reach a maximum of approximately 383K, approximately 230 degrees F, while keeping the instruments cold at a minimum of approximately 36K or around -394 degrees F.

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NASA release
Sunshield successfully deployed

The James Webb Space Telescope team has fully deployed the spacecraft's 70-foot sunshield, a key milestone in preparing it for science operations.

The sunshield – about the size of a tennis court at full size – was folded to fit inside the payload area of an Arianespace Ariane 5 rocket's nose cone prior to launch. The Webb team began remotely deploying the sunshield Dec. 28, 2021, three days after launch.

"This is the first time anyone has ever attempted to put a telescope this large into space," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate at the agency's headquarters in Washington. "Webb required not only careful assembly but also careful deployments. The success of its most challenging deployment – the sunshield – is an incredible testament to the human ingenuity and engineering skill that will enable Webb to accomplish its science goals."

The five-layered sunshield will protect the telescope from the light and heat of the Sun, Earth, and Moon. Each plastic sheet is about as thin as a human hair and coated with reflective metal, providing protection on the order of more than SPF 1 million. Together, the five layers reduce exposure from the Sun from over 200 kilowatts of solar energy to a fraction of a watt.

This protection is crucial to keep Webb's scientific instruments at temperatures of 40 kelvins, or under minus 380 degrees Fahrenheit – cold enough to see the faint infrared light that Webb seeks to observe.

"Unfolding Webb's sunshield in space is an incredible milestone, crucial to the success of the mission," said Gregory L. Robinson, Webb's program director at NASA Headquarters. "Thousands of parts had to work with precision for this marvel of engineering to fully unfurl. The team has accomplished an audacious feat with the complexity of this deployment – one of the boldest undertakings yet for Webb."

The unfolding occurred in the following order, over the course of eight days:

  • Two pallet structures – forward and aft – unfolded to bring the observatory to its full 70-foot length

  • The Deployable Tower Assembly deployed to separate the telescope and instruments from the sunshield and the main body of the spacecraft, allowing room for the sunshield to fully deploy

  • The aft momentum flap and membrane covers were released and deployed

  • The mid-booms deployed, expanding perpendicular to the pallet structures and allowing the sunshield to extend to its full width of 47 feet

  • Finally, at approximately 11:59 a.m. EST Tuesday, the sunshield was fully tensioned and secured into position, marking the completion of the sunshield deployment

  • The unfolding and tensioning of the sunshield involved 139 of Webb's 178 release mechanisms, 70 hinge assemblies, eight deployment motors, roughly 400 pulleys, and 90 individual cables totaling roughly one quarter of a mile in length. The team also paused deployment operations for a day to work on optimizing Webb's power systems and tensioning motors, to ensure Webb was in prime condition before beginning the major work of sunshield tensioning.
"The sunshield is remarkable as it will protect the telescope on this historic mission," said Jim Flynn, sunshield manager at Northrop Grumman, NASA's primary contractor for Webb. "This milestone represents the pioneering spirit of thousands of engineers, scientists, and technicians who spent significant portions of their careers developing, designing, manufacturing, and testing this first-of-its kind space technology."

The world's largest and most complex space science observatory has another 5 1/2 months of setup still to come, including deployment of the secondary mirror and primary mirror wings, alignment of the telescope optics, and calibration of the science instruments. After that, Webb will deliver its first images.

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NASA update
Secondary mirror deployment confirmed

Today (Jan. 5), Webb teams successfully deployed the observatory's secondary mirror support structure. When light from the distant universe hits Webb's iconic 18 gold primary mirrors, it will reflect off and hit the smaller, 2.4-foot (.74-meter) secondary mirror, which will direct the light into its instruments. The secondary mirror is supported by three lightweight deployable struts that are each almost 25 feet long and are designed to withstand the space environment. Specialized heating systems were used to warm up the joints and motors needed for seamless operation.

"Another banner day for JWST," said Bill Ochs, Webb project manager at NASA's Goddard Space Flight Center, as he congratulated the secondary mirror deployment team at the Mission Operations Center in Baltimore. "This is unbelievable... We're about 600,000 miles from Earth, and we actually have a telescope."

The deployment process began at approximately 9:52 a.m. EST, and the secondary mirror finished moving into its extended position at about 11:28 a.m. EST. The secondary mirror support structure was then latched at about 11:51 a.m. EST. At approximately 12:23 p.m. EST, engineers confirmed that the structure was fully secured and locked into place and the deployment was complete.

"The world's most sophisticated tripod has deployed," said Lee Feinberg, optical telescope element manager for Webb at Goddard. "That's really the way one can think of it. Webb's secondary mirror had to deploy in microgravity, and in extremely cold temperatures, and it ultimately had to work the first time without error. It also had to deploy, position, and lock itself into place to a tolerance of about one and a half millimeters, and then it has to stay extremely stable while the telescope points to different places in the sky – and that's all for a secondary mirror support structure that is over 7 meters in length."

Next Webb will deploy an important radiator system known as the aft deployable infrared radiator (ADIR), which helps shed heat away from its instruments and mirrors.

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NASA update
Heat radiator deployed

At about 8:48 a.m. EST on Thursday (Jan. 6), a specialized radiator assembly necessary for Webb's science instruments to reach their required low and stable operating temperatures deployed successfully.

The Aft Deployable Instrument Radiator, or ADIR, is a large, rectangular, 4 by 8-foot panel, consisting of high-purity aluminum subpanels covered in painted honeycomb cells to create an ultra-black surface. The ADIR, which swings away from the backside of the telescope like a trap door on hinges, is connected to the instruments via flexible straps made of high-purity aluminum foil. The radiator draws heat out of the instruments and dumps it overboard to the extreme cold background of deep space.

The deployment of the ADIR – a process that released a lock to allow the panel to spring into position – took about 15 minutes.

Webb's final series of major deployments is planned to start tomorrow, Jan. 7, with the rotation into position of the first of two primary mirror wings. The second primary wing – Webb's final major spacecraft deployment – is planned for Saturday, Jan. 8.

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NASA update
First of two primary mirror wings unfolds

Webb's iconic primary mirror is taking its final shape. Today (Jan. 7), the first of two primary mirror wings, or side panels, was deployed and latched successfully. Each side panel holds three primary mirror segments that were engineered to fold back to reduce Webb's overall profile for flight.

The process of deploying the port side mirror wing began at approximately 8:36 a.m. EST. At approximately 2:11 p.m. EST, engineers confirmed that the panel was fully secured and locked into place, and the deployment was complete.

Now that the port side wing panel is locked in place, ground teams will prepare to deploy and latch the starboard (right side) panel tomorrow. Upon completion, Webb will have concluded its major deployment sequence.

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Webb Space Telescope fully deployed after primary mirror unfolds

That's 18 not-so-small steps for a space telescope, one giant deployment for humanity's understanding of the universe.

The James Webb Space Telescope completed its deployment on Saturday (Jan. 8), two weeks after the observatory's launch. While there remains months of work before Webb can begin making astronomical discoveries, Saturday's milestone marked a significant step forward for the world's largest and most powerful space telescope.

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NASA release
Webb mirror segment deployments complete

Last week, the Webb team began moving the observatory's individual mirror segments out of their launch positions. Today (Jan. 19), we hear from Erin Wolf, Webb program manager at Ball Aerospace, about the completion of that process:

"Today, the James Webb Space Telescope team completed the mirror segment deployments. As part of this effort, the motors made over a million revolutions this week, controlled through 20 cryogenic electronics boxes on the telescope.

"The mirror deployment team incrementally moved all 132 actuators located on the back of the primary mirror segments and secondary mirror. The primary mirror segments were driven 12.5 millimeters away from the telescope structure. Using six motors that deploy each segment approximately half the length of a paper clip, these actuators clear the mirrors from their launch restraints and give each segment enough space to later be adjusted in other directions to the optical starting position for the upcoming wavefront alignment process.

"The 18 radius of curvature (ROC) actuators were moved from their launch position as well. Even against beryllium's strength, which is six times greater than that of steel, these ROC actuators individually shape the curvature of each mirror segment to set the initial parabolic shape of the primary mirror.

"Next up in the wavefront process, we will be moving mirrors in the micron and nanometer ranges to reach the final optical positions for an aligned telescope. The process of telescope alignment will take approximately three months."

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NASA update
Orbital insertion burn a success, Webb arrives at L2

Today (Monday, Jan. 24), at 2 p.m. EST (1900 GMT), Webb fired its onboard thrusters for nearly five minutes (297 seconds) to complete the final postlaunch course correction to Webb's trajectory. This mid-course correction burn inserted Webb toward its final orbit around the second Sun-Earth Lagrange point, or L2, nearly 1 million miles away from the Earth.

The final mid-course burn added only about 3.6 miles per hour (1.6 meters per second) – a mere walking pace – to Webb's speed, which was all that was needed to send it to its preferred "halo" orbit around the L2 point.

"Webb, welcome home!" said NASA Administrator Bill Nelson. "Congratulations to the team for all of their hard work ensuring Webb's safe arrival at L2 today. We're one step closer to uncovering the mysteries of the universe. And I can't wait to see Webb's first new views of the universe this summer!"

Webb's orbit will allow it a wide view of the cosmos at any given moment, as well as the opportunity for its telescope optics and scientific instruments to get cold enough to function and perform optimal science. Webb has used as little propellant as possible for course corrections while it travels out to the realm of L2, to leave as much remaining propellant as possible for Webb's ordinary operations over its lifetime: station-keeping (small adjustments to keep Webb in its desired orbit) and momentum unloading (to counteract the effects of solar radiation pressure on the huge sunshield).

"During the past month, JWST has achieved amazing success and is a tribute to all the folks who spent many years and even decades to ensure mission success," said Bill Ochs, Webb project manager at NASA's Goddard Space Flight Center. "We are now on the verge of aligning the mirrors, instrument activation and commissioning, and the start of wondrous and astonishing discoveries."

Now that Webb's primary mirror segments and secondary mirror have been deployed from their launch positions, engineers will begin the sophisticated three-month process of aligning the telescope's optics to nearly nanometer precision.

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NASA release
Photons incoming: Webb team begins aligning the telescope

This week, the three-month process of aligning the telescope began – and over the last day (Feb. 2-3), Webb team members saw the first photons of starlight that traveled through the entire telescope and were detected by the Near Infrared Camera (NIRCam) instrument. This milestone marks the first of many steps to capture images that are at first unfocused and use them to slowly fine-tune the telescope. This is the very beginning of the process, but so far the initial results match expectations and simulations.

A team of engineers and scientists from Ball Aerospace, Space Telescope Science Institute, and NASA's Goddard Space Flight Center will now use data taken with NIRCam to progressively align the telescope. The team developed and demonstrated the algorithms using a 1/6th scale model telescope testbed. They have simulated and rehearsed the process many times and are now ready to do this with Webb. The process will take place in seven phases over the next three months, culminating in a fully aligned telescope ready for instrument commissioning. The images taken by Webb during this period will not be "pretty" images like the new views of the universe Webb will unveil later this summer. They strictly serve the purpose of preparing the telescope for science.

To work together as a single mirror, the telescope's 18 primary mirror segments need to match each other to a fraction of a wavelength of light – approximately 50 nanometers. To put this in perspective, if the Webb primary mirror were the size of the United States, each segment would be the size of Texas, and the team would need to line the height of those Texas-sized segments up with each other to an accuracy of about 1.5 inches.

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NASA release
Photons Received: Webb Sees Its First Star – 18 Times

The James Webb Space Telescope is nearing completion of the first phase of the months-long process of aligning the observatory's primary mirror using the Near Infrared Camera (NIRCam) instrument.

The team's challenge was twofold: confirm that NIRCam was ready to collect light from celestial objects, and then identify starlight from the same star in each of the 18 primary mirror segments. The result is an image mosaic of 18 randomly organized dots of starlight, the product of Webb's unaligned mirror segments all reflecting light from the same star back at Webb's secondary mirror and into NIRCam's detectors.

What looks like a simple image of blurry starlight now becomes the foundation to align and focus the telescope in order for Webb to deliver unprecedented views of the universe this summer. Over the next month or so, the team will gradually adjust the mirror segments until the 18 images become a single star.

"The entire Webb team is ecstatic at how well the first steps of taking images and aligning the telescope are proceeding. We were so happy to see that light makes its way into NIRCam," said Marcia Rieke, principal investigator for the NIRCam instrument and regents professor of astronomy, University of Arizona.

Above: This image mosaic was created by pointing the telescope at a bright, isolated star in the constellation Ursa Major known as HD 84406. This star was chosen specifically because it is easily identifiable and not crowded by other stars of similar brightness, which helps to reduce background confusion. Each dot within the mosaic is labeled by the corresponding primary mirror segment that captured it. These initial results closely match expectations and simulations. (NASA)

During the image capturing process that began Feb. 2, Webb was repointed to 156 different positions around the predicted location of the star and generated 1,560 images using NIRCam's 10 detectors, amounting to 54 gigabytes of raw data. The entire process lasted nearly 25 hours, but notedly the observatory was able to locate the target star in each of its mirror segments within the first six hours and 16 exposures. These images were then stitched together to produce a single, large mosaic that captures the signature of each primary mirror segment in one frame. The images shown here are only a center portion of that larger mosaic, a huge image with over 2 billion pixels.

"This initial search covered an area about the size of the full Moon because the segment dots could potentially have been that spread out on the sky," said Marshall Perrin, deputy telescope scientist for Webb and astronomer at the Space Telescope Science Institute. "Taking so much data right on the first day required all of Webb's science operations and data processing systems here on Earth working smoothly with the observatory in space right from the start. And we found light from all 18 segments very near the center early in that search! This is a great starting point for mirror alignment."

Each unique dot visible in the image mosaic is the same star as imaged by each of Webb's 18 primary mirror segments, a treasure trove of detail that optics experts and engineers will use to align the entire telescope. This activity determined the post-deployment alignment positions of every mirror segment, which is the critical first step in bringing the entire observatory into a functional alignment for scientific operations.

NIRCam is the observatory's wavefront sensor and a key imager. It was intentionally selected to be used for Webb's initial alignment steps because it has a wide field of view and the unique capability to safely operate at higher temperatures than the other instruments. It is also packed with customized components that were designed to specifically aid in the process. NIRCam will be used throughout nearly the entire alignment of the telescope's mirrors. It is, however, important to note that NIRCam is operating far above its ideal temperature while capturing these initial engineering images, and visual artifacts can be seen in the mosaic. The impact of these artifacts will lessen significantly as Webb draws closer to its ideal cryogenic operating temperatures.

"Launching Webb to space was of course an exciting event, but for scientists and optical engineers, this is a pinnacle moment, when light from a star is successfully making its way through the system down onto a detector," said Michael McElwain, Webb observatory project scientist, NASA's Goddard Space Flight Center.

Above: This "selfie" was created using a specialized pupil imaging lens inside of the NIRCam instrument that was designed to take images of the primary mirror segments instead of images of space. This configuration is not used during scientific operations and is used strictly for engineering and alignment purposes. In this case, the bright segment was pointed at a bright star, while the others aren't currently in the same alignment. This image gave an early indication of the primary mirror alignment to the instrument. (NASA)

Moving forward, Webb's images will only become clearer, more detail-laden, and more intricate as its other three instruments arrive at their intended cryogenic operating temperatures and begin capturing data. The first scientific images are expected to be delivered to the world in the summer. Though this is a big moment, confirming that Webb is a functional telescope, there is much ahead to be done in the coming months to prepare the observatory for full scientific operations using all four of its instruments.

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NASA release
NASA's Webb Reaches Alignment Milestone, Optics Working Successfully

Following the completion of critical mirror alignment steps, NASA's James Webb Space Telescope team expects that Webb's optical performance will be able to meet or exceed the science goals the observatory was built to achieve.

Above: While the purpose of this image was to focus on the bright star at the center for alignment evaluation, Webb's optics and NIRCam are so sensitive that the galaxies and stars seen in the background show up. At this stage of Webb's mirror alignment, known as "fine phasing," each of the primary mirror segments have been adjusted to produce one unified image of the same star using only the NIRCam instrument. This image of the star, which is called 2MASS J17554042+6551277, uses a red filter to optimize visual contrast. (NASA/STScI)

On March 11, the Webb team completed the stage of alignment known as "fine phasing." At this key stage in the commissioning of Webb's Optical Telescope Element, every optical parameter that has been checked and tested is performing at, or above, expectations. The team also found no critical issues and no measurable contamination or blockages to Webb's optical path. The observatory is able to successfully gather light from distant objects and deliver it to its instruments without issue.

Although there are months to go before Webb ultimately delivers its new view of the cosmos, achieving this milestone means the team is confident that Webb's first-of-its-kind optical system is working as well as possible.

"More than 20 years ago, the Webb team set out to build the most powerful telescope that anyone has ever put in space and came up with an audacious optical design to meet demanding science goals," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate in Washington. "Today we can say that design is going to deliver."

While some of the largest ground-based telescopes on Earth use segmented primary mirrors, Webb is the first telescope in space to use such a design. The 21-foot, 4-inch (6.5-meter) primary mirror – much too big to fit inside a rocket fairing – is made up of 18 hexagonal, beryllium mirror segments. It had to be folded up for launch and then unfolded in space before each mirror was adjusted – to within nanometers – to form a single mirror surface.

"In addition to enabling the incredible science that Webb will achieve, the teams that designed, built, tested, launched, and now operate this observatory have pioneered a new way to build space telescopes," said Lee Feinberg, Webb optical telescope element manager at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Above: This new "selfie" was created using a specialized pupil imaging lens inside of the NIRCam instrument that was designed to take images of the primary mirror segments instead of images of the sky. This configuration is not used during scientific operations and is used strictly for engineering and alignment purposes. In this image, all of Webb's 18 primary mirror segments are shown collecting light from the same star in unison. (NASA/STScI)

With the fine phasing stage of the telescope's alignment complete, the team has now fully aligned Webb's primary imager, the Near-Infrared Camera, to the observatory's mirrors.

"We have fully aligned and focused the telescope on a star, and the performance is beating specifications. We are excited about what this means for science," said Ritva Keski-Kuha, deputy optical telescope element manager for Webb at NASA Goddard. "We now know we have built the right telescope."

Over the next six weeks, the team will proceed through the remaining alignment steps before final science instrument preparations. The team will further align the telescope to include the Near-Infrared Spectrograph, Mid-Infrared Instrument, and Near InfraRed Imager and Slitless Spectrograph. In this phase of the process, an algorithm will evaluate the performance of each instrument and then calculate the final corrections needed to achieve a well-aligned telescope across all science instruments. Following this, Webb's final alignment step will begin, and the team will adjust any small, residual positioning errors in the mirror segments.

The team is on track to conclude all aspects of Optical Telescope Element alignment by early May, if not sooner, before moving on to approximately two months of science instrument preparations. Webb's first full-resolution imagery and science data will be released in the summer.


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