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Artykuły o JWST
« dnia: Styczeń 31, 2020, 00:14 »
GAO warns of more JWST delays
by Jeff Foust — January 28, 2020


The GAO report cited a NASA analysis in October that projected only a 12% chance of launching by March 2021. Credit: NASA/Chris Gunn

WASHINGTON — A report by the U.S. Government Accountability Office Jan. 28 concluded it was unlikely that NASA’s James Webb Space Telescope will launch on schedule next March, with a delay of several months possible.

The GAO report, the latest in an annual series on the progress NASA is making on the flagship space observatory, argued that high consumption of schedule reserve in the first half of 2019 means the current March 2021 launch date “may not be feasible” given the work remaining before launch.

The report noted that the program performed an updated joint confidence level analysis of the mission’s cost in schedule in October. “Because of schedule delays resulting from technical challenges coupled with remaining risks faced by the project, the analysis assessed only a 12 percent confidence level for the project’s ability to meet the March 2021 launch readiness date,” the report stated.

NASA missions usually set cost and schedule estimates at the 70% confidence level. Using that metric, the launch would likely take place in July 2021, a delay of four months, according to the report.

Concerns about the high use of schedule reserve since NASA replanned the mission for a 2021 launch go back to last March. Tom Young, who chaired the Independent Review Board chartered by NASA in 2018 to review the mission, said that use of schedule reserve appeared to be “significantly higher” than expected. “It suggested to us there was cause for concern,” he said at a National Academies meeting.

By late October, NASA officials acknowledged that the mission’s schedule reserve had shrunk to two months, consistent with the last data point in the GAO report. Since then, though, use of schedule reserve has stabilized: at a JWST town hall meeting during an American Astronomical Society conference in Honolulu Jan. 5, program leaders said the mission still had two months of schedule reserve remaining.

“In the second half of 2019, schedule erosion has diminished significantly, and that’s what gives us a lot of confidence to still press to that March 2021 launch date,” said Greg Robinson, the JWST program director at NASA Headquarters, during a Jan. 6 interview at the conference.

Both he and Scott Willoughby, vice president and program manager for JWST at prime contractor Northrop Grumman, said they believed the mission was on track to complete a final set of environmental and deployment tests and be shipped to the launch site at Kourou, French Guiana, by the end of the year.

That confidence, Willoughby said, was in part because much of that remaining work has already been done in one form or another during earlier work on the spacecraft. “All of the work that’s planned in front of us is very well understood,” he said. “If everything goes as planned, the schedule is very much sufficient to get us there.”

By contrast, the GAO report concluded that the mission was entering a phase where delays are more likely. “Our previous work on major NASA acquisition programs found that integration and testing is the phase when challenges are most likely to be found and schedules can slip,” it stated.

The GAO said the JWST program plans to reassess its launch date in the spring after completing “significant technical tasks” with the mission. Robinson, in the Jan. 6 interview, said the schedule will be reassessed in May prior to the final set of environmental tests for the spacecraft.


Source: https://spacenews.com/gao-warns-of-more-jwst-delays/
« Ostatnia zmiana: Maj 13, 2021, 14:51 wysłana przez Orionid »

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Odp: [SN] GAO warns of more JWST delays
« Odpowiedź #1 dnia: Styczeń 31, 2020, 07:52 »
Government watchdog warns of another JWST launch delay
January 30, 2020 Stephen Clark [SFN]


The James Webb Space Telescope is pictured during a sunshield deployment test in October 2019 at a Northrop Grumman facility in Redondo Beach, California. Credit: NASA/Chris Gunn

The James Webb Space Telescope is at risk of another launch delay beyond the mission’s current target launch date in March 2021, the Government Accountability Office said this week.

The GAO reported Tuesday that new technical challenges on the multibillion-dollar international project have raised doubts about the March 2021 launch date, which is already more than six years later than the mission’s original official schedule established in 2009.

NASA announced the March 2021 launch schedule in 2018 following an independent cost and schedule review. The independent review board assessed the status of Webb after NASA determined the mission would be ready for liftoff in 2018, when the observatory was previously scheduled to launch.

Teams working in Northrop Grumman’s spacecraft factory in Southern California connected the spacecraft and science modules of JWST last August, forming the complete observatory for the first time.

“However, new technical challenges have required the project to use more schedule reserve — extra time set aside in the project’s schedule to accommodate unforeseen risks or delays — than planned,” the GAO said Tuesday.

While NASA officials formally announced a target launch date in March 2021, managers internally hoped to ready the observatory for liftoff by November 2020. They gave up on that hope last year.

“The project is now managing to a March 2021 launch date but estimates only a 12 percent likelihood that this date will be achieved,” the GAO said. “NASA plans to reassess the launch date in the spring of 2020.”

NASA project managers typically set target launch dates with a 70 percent confidence level. An analysis of the current schedule shows that a launch date for Webb in July 2021 would meet that confidence level, according to the GAO.

With Webb fully assembled, engineers at Northrop Grumman — NASA’s prime contractor for the observatory — planned to put the craft through a series of deployment, electrical, vibration acoustic tests to ensure it will work as designed after launch aboard a European Ariane 5 rocket from French Guiana.

The Webb telescope is the largest space-based observatory ever developed, with a primary mirror stretching 21.3 feet (6.5 meters) wide, comprised of 18 hexagonal segments made of beryllium and coated in gold. Two side sections of the primary mirror are mounted on folding wings that will be closed up for launch, then open once the observatory is in space.

The spacecraft’s tennis court-sized, five-layer sunshield, which will keep the telescope cool in space, will also be folded and stowed for launch. Antennas, solar arrays, and the telescope’s structure will also have to open and unfurl after Webb’s separation from its Ariane 5 launcher.

Webb has more deployments after launch than a typical science mission. By some measures, it has more than four times more deployments to accomplish its mission than NASA’s Curiosity rover needed to get to the surface of Mars.

Scientists say the James Webb Space Telescope’s four infrared science instruments — which come from U.S., European and Canadian institutions — will see the very first stars and galaxies in the universe, observing light emitted some 13.5 billion years ago. With imaging power 100 times that of the Hubble Space Telescope, Webb will also peer into star-forming nebulas and collect data on the physical and chemical properties of planets around other stars.

In its report Tuesday, the GAO said the cost of the JWST project to NASA has risen 95 percent to $9.7 billion since the space agency established a schedule and budget baseline for the mission in 2009. That figure does not include contributions from Europe and Canada, which push the total mission cost well over $10 billion.

According to the GAO, multiple technical issues have contributed to the use of schedule reserves since 2018, but two issues identified in March and April 2019 had the most significant effect.

“Specifically, a traveling wave tube amplifier and a command and telemetry processor had errant powering issues during testing,” the GAO said. “These are important components of the observatory’s communication systems that enable JWST to send large amounts of science data and telemetry to the ground segment at high speed.”

NASA does not believe the issues are related, and the amplifier failure was attributed to workmanship issues at a subcontractor. As of October, the exact cause of the processor anomaly remained under investigation, but the electrical problem was isolated to faults within specific circuit cards, according to the GAO.

“NASA has taken steps to address the risks presented by both anomalies: it has received replacement amplifiers and has upgraded and tested an engineering model processor to replace the faulty one aboard the observatory if necessary,” the GAO said.



Credit: NASA

While the technical issues used up some of the Webb program’s schedule reserve, Northrop Grumman has been able to reclaim some of the extra time by finding scheduling and work flow efficiencies, according to the GAO.

“Technical challenges also resulted in longer employment of the contractor workforce than planned, which could result in additional cost increases,” the GAO said. “NASA continues to monitor multiple, other risks that could place further schedule and cost strains on the project.

“Since NASA replanned the project again in June 2018, the agency has taken steps meant to improve performance and oversight,” the GAO said. “NASA has addressed all recommendations from an independent review board, but in doing so sometimes took actions that differed from those outlined in the board’s report.”


Source: https://spaceflightnow.com/2020/01/30/government-watchdog-warns-of-another-jwst-launch-delay/

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Odp: [SN] GAO warns of more JWST delays
« Odpowiedź #2 dnia: Kwiecień 07, 2020, 06:50 »
Limited work continues on JWST
by Jeff Foust — April 2, 2020 [SN]


NASA's James Webb Space Telescope deployed its primary mirror in an early March test, but work on the spacecraft is currently limited because of the coronavirus pandemic. Credit: NASA/Chris Gunn

WASHINGTON — While NASA has resumed some work on the James Webb Space Telescope, project officials say even that limited level of activity will soon come to a halt because of the coronavirus pandemic.

NASA announced March 20 that it suspended work on the space telescope, which had been undergoing integration and testing, or I&T, activities at a Northrop Grumman facility in Southern California. That decision was made “to ensure the safety of the workforce,” NASA said in a statement.

However, the project announced March 25 that it had decided to resume some work “with reduced personnel and shifts” through early April. “We’ll assess and adjust decisions as the situation unfolds,” the project tweeted.

That work is continuing with only a small fraction of the NASA personnel usually present. “We were running about 45, sometimes 50 people out there on a weekly basis. We’re down to 15 now,” said Bill Ochs, JWST project manager at NASA’s Goddard Space Flight Center, during a March 31 online meeting of the National Academies’ Committee on Astronomy and Astrophysics.

“We are doing some I&T activities, but it’s not at the rate that we had been doing them,” he said of current work. What work is taking place is being carefully evaluated to make sure it’s safe, he said, including changes like new cleanroom procedures to maintain distance between personnel and limiting the number of the people in the “gowning area” at any one time preparing to go into the cleanroom.

That reduced level of work will continue until just before a test of the Deployable Tower Assembly, a core structure that supports the spacecraft and telescope sections of JWST, scheduled for early April. “At that point we will shut down I&T operations,” Ochs said. “Activities from that point forward require the full NASA and Northrop team.” Some of those activities, he added, will also require personnel from international partners contributing instruments to the telescope.

The effects of the coronavirus pandemic on the project extend beyond activities at Northrop Grumman. Goddard is at Stage 4 of NASA’s response framework, closing the center to all but the most essential personnel and halting travel. “We have an exception for JWST, but we have taken a very conservative approach,” he said. The Space Telescope Science Institute, which handles science operations, is closed through at least April 10.

Before the onset of the pandemic, the project had been making good progress preparing the telescope for a launch still scheduled for March 2021. That included the replacement of a command and telemetry processor and traveling wave tube amplifiers on the spacecraft in January, replacing components that failed in earlier tests. The telescope also deployed its primary mirror in a test in early March.

Ochs said that, before the slowdown in work on JWST, the project had 52 days of schedule reserve remaining. How much of a delay the pandemic might cause in its launch won’t be clear until after the pandemic ends. “Once we hit the other side of this, we will then do a full evaluation of where we are with the JWST schedule,” he said.

JWST’s current budget could handle a launch delay of a few months without additional costs, he added. “We can probably go months past at this point, at least a few months,” he said. “But if we go beyond that, then you would have an issue with money.”


Source: https://spacenews.com/limited-work-continues-on-jwst/

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Odp: [SN] NASA delays JWST launch by seven months
« Odpowiedź #3 dnia: Lipiec 17, 2020, 23:53 »
NASA delays JWST launch by seven months
by Jeff Foust — July 16, 2020


JWST July 2020
NASA's James Webb Space Telescope undergoing testing at a Northrop Grumman facility in July. NASA announced July 16 that the mission's launch will be delayed by seven months, to the end of October 2021. Credit: NASA/Chris Gunn

WASHINGTON — NASA announced July 16 that it is delaying the launch of its largest-ever space observatory, the James Webb Space Telescope, by seven months to address both technical issues as well as the effects of the coronavirus pandemic.

Agency officials said in a media teleconference that the launch of JWST is now projected for Oct. 31, 2021. The agency had previously scheduled the launch for the end of March 2021.

Greg Robinson, the program director for JWST at NASA, said that “three-plus” months of the delay is caused by the pandemic, including effects on the program to date as well as declines in efficiency in future activities because of new procedures that slow down the pace of work on the telescope at a Northrop Grumman facility in Southern California. That work briefly halted in March because of the pandemic, then continued at a slower pace for a couple months before the company was able to resume “near-full” shifts.

Another two months of the delay is to add schedule reserve to the program. Robinson said that the mission, which had two months of schedule reserve remaining at the beginning of the year, now had three months to comply with agency best practices for program management. “We think we have a robust reserve,” he said.

The rest of the delay is to provide additional time for remaining test activities, including acoustics and vibration testing and a deployment test of the spacecraft’s sunshield. That additional time, Robinson said, was based on “learning how to do certain activities” from earlier phases of the program.

This latest launch delay was not a surprise. Thomas Zurbuchen, NASA associate administrator for science, said June 10 that JWST would miss its March 2021 launch date because of a slowdown in activities caused by the pandemic. He declined then to set a new launch date, saying that program was still assessing the effect of the pandemic on mission activities.

Even before the pandemic, though, there were concerns that technical issues would delay the launch, based on the program’s use of its schedule reserves. NASA Associate Administrator Steve Jurczyk said during the media call that the agency had scheduled a review of the mission’s status in April because of those diminishing reserves, but postponed it because of the pandemic.

The delay won’t increase the cost of JWST, which has a cost cap set by Congress of $8.8 billion through launch. “Based on current projections, the program expects to complete the remaining work within the new schedule without requiring additional funds,” Robinson said, by making use of existing budget reserves.

“There were reserves that we were holding,” Jurczyk said, “to handle these kinds of unforeseen issues, like schedule slips. Those reserves are now being deployed.” Officials, though, didn’t say if the delay would deplete those budget reserves.

Zurbuchen said NASA has already discussed the delay with the European Space Agency, who will launch JWST on an Ariane 5 rocket from French Guiana, and did not anticipate any issues. “This fits well into the manifest of Ariane 5,” he said.

Agency officials emphasized in the media call the valuable science that JWST will perform is worth this delay, the latest in a series of delays that pushed back the launch of the space telescope by several years. “We’re opening up an entirely new horizon of discoveries about our universe with the Webb Telescope,” Zurbuchen said. “Our important work provides inspiration to everyone.”

First, though, JWST has to finish testing, be launched and complete a complex series of deployments of its mirror and sunshield once in space. “I will be holding my breath until we get all the deployments done and get the observatory into its science configuration,” Jurczyk said.


Source: https://spacenews.com/nasa-delays-jwst-launch-by-seven-months/
« Ostatnia zmiana: Kwiecień 07, 2021, 18:59 wysłana przez Orionid »

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Odp: [SN] NASA delays JWST launch by seven months
« Odpowiedź #3 dnia: Lipiec 17, 2020, 23:53 »

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Artykuły o JWST
« Odpowiedź #4 dnia: Maj 13, 2021, 14:50 »
Ariane 5 issue could delay JWST
by Jeff Foust — May 12, 2021


An Ariane 5 launches in August 2020, carrying three satellites. A "less than fully nominal separation of the fairing" on that launch, and the one before that, has resulted in investigations that have kept the vehicle grounded for months. Credit: ESA/CNES/Arianespace

WASHINGTON — Ongoing work to address a problem seen on two previous Ariane 5 launches has kept that launch vehicle grounded for months and could delay the high-profile launch of NASA’s James Webb Space Telescope later this year.

The Ariane 5, one of the world’s most reliable launch vehicles, last launched in August 2020, placing two communications satellites and Northrop Grumman’s Mission Extension Vehicle 2 into geostationary transfer orbit. The long hiatus in launches led to speculation there was an issue with the rocket.

Source: https://spacenews.com/ariane-5-issue-could-delay-jwst/

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Odp: Artykuły o JWST
« Odpowiedź #5 dnia: Maj 14, 2021, 12:57 »
James Webb Space Telescope's golden mirror in final test
Jonathan Amos Science correspondent [BBC] Published 1 day ago



The technological marvel that is the James Webb Space Telescope (JWST) is going through final testing before being shipped to the launch site.

The successor to the mighty Hubble is due to leave Earth in October to begin a new era of astronomical discovery. (...)

The European Space Agency (Esa), a key partner on the project, is providing the launch vehicle - an Ariane-5. Lift-off is scheduled for 31 October.

The days following will be exciting, and anxiety-laden. If Mars landers face "seven minutes of terror" when making the hazardous descent to the Red Planet's surface, then Webb will experience "two weeks of terror" as it unpacks all its systems on the way out to its observing position some 1.5 million km from Earth. (...)

"If we get to the point where we're starting to run out of fuel, they might be able to mount a mission to go out and refuel JWST to keep it going," Nasa project manager Bill Ochs told reporters. (...)

Source: https://www.bbc.com/news/science-environment-57078657

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Odp: Artykuły o JWST
« Odpowiedź #6 dnia: Czerwiec 04, 2021, 02:21 »
JWST launch slips to November
by Jeff Foust — June 2, 2021 [SN]


ESA and Arianespace said they are finalizing corrective actions to address a payload fairing separation issue sene on two Ariane 5 launches in 2020, setting up for a launch of JWST no earlier than November. Credit: ESA - D. Ducros

WASHINGTON — American and European officials acknowledged June 1 that the launch of the James Webb Space Telescope will likely slip from the end of October to at least mid-November because of delays linked to the Ariane 5.

At a European Space Agency briefing about the space telescope, representatives of the agency and Arianespace said they were finalizing reviews to correct a payload fairing problem found on two Ariane 5 launches last year that had grounded the rocket since August. Arianespace described the issue last month as “a less than fully nominal separation of the fairing” on those two launches.

Source: https://spacenews.com/jwst-launch-slips-to-november/

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Odp: Artykuły o JWST
« Odpowiedź #7 dnia: Wrzesień 09, 2021, 22:38 »
JWST gets mid-December launch date
by Jeff Foust — September 9, 2021 [SN]


NASA's James Webb Space Telescope is now scheduled to launch Dec. 18 on an Ariane 5. Credit: ESA - D. Ducros

WASHINGTON — NASA’s James Webb Space Telescope is finally scheduled to launch Dec. 18 on an Ariane 5 from French Guiana after years of development delays.

NASA, the European Space Agency and Arianespace announced Sept. 8 that they had selected Dec. 18 as the formal targeted launch date for the giant space observatory. ESA is providing the launch as part of its contribution to the NASA-led mission in exchange for a share of observing time.

Source: https://spacenews.com/jwst-gets-mid-december-launch-date/

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Odp: Artykuły o JWST
« Odpowiedź #8 dnia: Październik 22, 2021, 15:22 »
NASA defends decision to retain JWST name
by Jeff Foust — October 20, 2021 [SN]


NASA Administrator James Webb (right) with former President Harry Truman outside NASA Headquarters in 1961. A NASA historical review found no evidence Webb was involved in discriminatory actions against LGBTQ employees at NASA or the State Department. Credit: NASA

WASHINGTON — NASA officials are standing by their decision to retain the name of the James Webb Space Telescope despite criticism from some astronomers, including one who resigned from an advisory committee in protest.

Source: https://spacenews.com/nasa-defends-decision-to-retain-jwst-name/

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Odp: Artykuły o JWST
« Odpowiedź #9 dnia: Listopad 23, 2021, 21:45 »
Webb telescope launch delayed to investigate clean room incident
November 22, 2021 Stephen Clark  EDITOR’S NOTE: Updated Nov. 23 with details from NASA. [SFN]


The James Webb Space Telescope inside its clean room in French Guiana. Credit: ESA/CNES/Arianespace/P. Piron

NASA said Monday the launch of the $9.7 billion James Webb Space Telescope will be delayed at least four days until no earlier than Dec. 22 out of “sheer caution” to ensure the observatory suffered no damage from vibrations during a processing incident at its launch site in French Guiana.

Source: https://spaceflightnow.com/2021/11/22/webb-telescope-launch-delayed-to-investigate-clean-room-incident/
« Ostatnia zmiana: Listopad 25, 2021, 08:40 wysłana przez Orionid »

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Odp: Artykuły o JWST
« Odpowiedź #10 dnia: Listopad 23, 2021, 21:45 »
JWST launch slips after payload processing incident
by Jeff Foust — November 22, 2021 [SN]


NASA said it was delaying the launch of the James Webb Space Telescope by at least four days out of an abundance of caution after a launch adapter clamp unexpectedly came off during payload processing. Credit: NASA/Chris Gunn

WASHINGTON — NASA announced Nov. 22 that it is delaying the launch of the James Webb Space Telescope by at least four days to investigate an incident that took place preparing the spacecraft for launch in French Guiana.

Source: https://spacenews.com/jwst-launch-slips-after-payload-processing-incident/

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Odp: Artykuły o JWST
« Odpowiedź #11 dnia: Dzisiaj o 16:58 »
JWST undamaged from payload processing incident
by Jeff Foust — November 25, 2021 [SN]


Testing of JWST found no damage to the spacecraft after a payload processing incident earlier this month that caused its launch to slip four days. Credit: NASA/Chris Gunn

WASHINGTON — Launch preparations for NASA’s James Webb Space Telescope will resume after testing found no damage to the spacecraft from a payload processing incident earlier this month.

Source: https://spacenews.com/jwst-undamaged-from-payload-processing-incident/

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