JWST – Ariane 5 ECA – Kourou ELA-3 – 25.12.2021 12:20 UTC

Автор zandr, 28.03.2018 21:09:50

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tnt22

ЦитироватьGrant Tremblay‏ @astrogrant 21 ч. назад

Updated plot of #JWST Budget/Launch Date projections. Each blue dot was one such media advisory. I'm genuinely not trying to be snarky - JWST will do transformational science - but this ... this isn't a good look.


tnt22

http://spacenews.com/jwst-suffers-another-launch-delay-breaches-cost-cap/
ЦитироватьJWST suffers another launch delay, breaches cost cap
by Jeff Foust — June 27, 2018


NASA will seek congressional reauthorization of the James Webb Space Telescope after an independent review found it would not be ready for launch until late March 2021 and break an $8 billion cost cap by 10 percent. Credit: NASA artist's concept

RENTON, Wash. — NASA announced yet another launch delay for the James Webb Space Telescope June 27, pushing the flagship observatory's launch to no earlier than late March 2021 while breaking a cost cap set by Congress.

NASA said it was now aiming for a launch of the telescope on March 30, 2021, nearly a year later than the May 2020 date that the agency announced three months earlier. That date came after a delay announced last September that moved the mission's launch from October 2018 to the spring of 2019.

NASA also announced a new development cost estimate of $8.8 billion, which is 10 percent above the $8 billion cost cap established by Congress during a "re-plan" of the mission several years ago. The overall lifecycle cost of the mission, which includes operations after launch for at least five years, is $9.66 billion.

The new development cost breaches the cost cap, which will require Congress to formally reauthorize the mission. NASA Associate Administrator Steve Jurczyk said in a media teleconference that the agency had filed a final breach report with Congress earlier this week because of both the cost and schedule slip and would seek formal reauthorization as part of the fiscal year 2019 appropriations process.
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"I think it's too early to really give an exact sense of what's happening there," said Thomas Zurbuchen, NASA associate administrator for science, of congressional reaction to the latest delay. He said his meetings gave the impression that Congress thought the science of JWST was still compelling, but it was premature to further assess the mood on Capitol Hill.

Jurczyk said NASA would need $837 million in additional funding in the "outyears" beyond 2019 compared to the administration's fiscal year 2019 budget request published in February. The agency is currently working on its fiscal year 2020 proposal, he said, but didn't indicate how much additional funding he expected NASA would need in 2020 versus later years.

The revised schedule and cost came after the completion of an independent review board that NASA chartered in March. That report offered about 30 recommendations that NASA had accepted to revise the development of JWST and its oversight of work at prime contractor Northrop Grumman.

"It was our assessment that there was still too much optimism built into the schedule," said the board's chair, Tom Young, even after the previous slip to May 2020. "We implemented in our view a more realistic assessment as to the time it would take to do these various events."

Another factor was a problem discovered during an acoustics test at the end of April that caused fasteners in the spacecraft's sunshield to come loose. That has caused a delay "something in the neighborhood of" six months, he said, to study the problem and retrieve fasteners that came loose inside the spacecraft.

The two-and-a-half-year delay in the JWST has five root causes, Young said, including human errors, embedded problems, lack of experience in new technologies like the sunshield, excessive optimism and systems complexity.

One such example of human error was damage to spacecraft valves when workers used the wrong solvent to clean them, having failed to check with the vendor. Such human errors, he said, accounted for 18 months of schedule delay and $600 million in additional costs.

Maintaining the new schedule requires implementing measures to minimize human errors and to identify other embedded problems with the spacecraft, according to Young. "If the recommendations on human errors and the recommendations on embedded problems are rigorously implemented, which I expect they will be, then I think we have a very high probability" of preventing problems that would have a significant schedule impact, he said.

Young, though, said that there was no reason to reconsider flying the mission at all. "JWST should continue because of the compelling science and because of JWST's national importance," he said.
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tnt22

ЦитироватьJames Webb Space Telescope: Worth the Wait

NASA Goddard

Опубликовано: 27 июн. 2018 г.

Building the James Webb Space Telescope is challenging. It is NASA's most ambitious and complex space science observatory. The mission required 10 new technologies to be invented, the dedication of hundreds of scientists, engineers and technicians testing and retesting each component. It is by no means easy, but the telescope is so incredibly powerful that major findings are expected in nearly every branch of astronomy. It is worth the wait.
https://www.youtube.com/watch?v=kd71-d-o1Fghttps://www.youtube.com/watch?v=kd71-d-o1Fg (0:31)

tnt22

ЦитироватьNASA Science Leaders: Webb Telescope Complex and Unprecedented

NASA

Опубликовано: 27 июн. 2018 г.

Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate, and John Mather, senior project scientist, comment on an independent review board's findings on the agency's James Webb Space Telescope. Webb is now targeting March 2021 as a new launch date, after the board assessed delays in integration and testing. NASA and the board unanimously agree that Webb can still achieve mission success.
https://www.youtube.com/watch?v=M7mYVftosSchttps://www.youtube.com/watch?v=M7mYVftosSc (3:20)

tnt22

Оправдывает переименование, ибо долгострой-с-с...
ЦитироватьJonathan McDowell‏Подлинная учетная запись @planet4589 4 ч. назад

JWST, the Just Wait Space Telescope, now slipped to 2021.

Чебурашка

Ставим ставки, что позже улетит МЛМ и JWST..
Оба проекта почти одновременно начинались  :D

tnt22

ЦитироватьAdministrator Bridenstine: NASA is Committed to Webb Telescope

NASA

Опубликовано: 27 июн. 2018 г.

NASA Administrator Jim Bridenstine discusses the findings of the Independent Review Board on one of our flagship missions, the James Webb Space Telescope. Despite Webb's major challenges during the final testing and integration phase, the board and NASA unanimously agreed that Webb will achieve mission success with the implementation of the board's recommendations, many of which are already underway.
https://www.youtube.com/watch?v=6CmtZLKgIWshttps://www.youtube.com/watch?v=6CmtZLKgIWs (2:04)

tnt22

ЦитироватьHow Do We Learn About a Planet's Atmosphere?

Space Telescope Science Institute

Опубликовано: 11 июл. 2018 г.

This animation describes how Webb will use transmission spectroscopy to study the atmospheres of distant exoplanets.
https://www.youtube.com/watch?v=Ppc1N3k8pYYhttps://www.youtube.com/watch?v=Ppc1N3k8pYY (2:11)

tnt22

https://www.nasa.gov/feature/goddard/2018/nasa-s-webb-space-telescope-to-inspect-atmospheres-of-gas-giant-exoplanets
ЦитироватьJuly 11, 2018

NASA's Webb Space Telescope to Inspect Atmospheres of Gas Giant Exoplanets

In April 2018, NASA launched the Transiting Exoplanet Survey Satellite (TESS). Its main goal is to locate Earth-sized planets and larger "super-Earths" orbiting nearby stars for further study. One of the most powerful tools that will examine the atmospheres of some planets that TESS discovers will be NASA's James Webb Space Telescope. Since observing small exoplanets with thin atmospheres like Earth will be challenging for Webb, astronomers will target easier, gas giant exoplanets first.
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This is an artist's impression of the Jupiter-size extrasolar planet, HD 189733b, being eclipsed by its parent star. Astronomers using the Hubble Space Telescope have measured carbon dioxide and carbon monoxide in the planet's atmosphere. The planet is a "hot Jupiter," which is so close to its star that it completes an orbit in only 2.2 days. The planet is too hot for life as we know it. But under the right conditions, on a more Earth-like world, carbon dioxide can indicate the presence of extraterrestrial life. This observation demonstrates that chemical biotracers can be detected by space telescope observations.
Credits: ESA, NASA, M. Kornmesser (ESA/Hubble), and STScI

Some of Webb's first observations of gas giant exoplanets will be conducted through the Director's Discretionary Early Release Science program. The transiting exoplanet project team at Webb's science operations center is planning to conduct three different types of observations that will provide both new scientific knowledge and a better understanding of the performance of Webb's science instruments.

"We have two main goals. The first is to get transiting exoplanet datasets from Webb to the astronomical community as soon as possible. The second is to do some great science so that astronomers and the public can see how powerful this observatory is," said Jacob Bean of the University of Chicago, a co-principal investigator on the transiting exoplanet project.

"Our team's goal is to provide critical knowledge and insights to the astronomical community that will help to catalyze exoplanet research and make the best use of Webb in the limited time we have available," added Natalie Batalha of NASA Ames Research Center, the project's principal investigator.

Transit – An atmospheric spectrum

When a planet crosses in front of, or transits, its host star, the star's light is filtered through the planet's atmosphere. Molecules within the atmosphere absorb certain wavelengths, or colors, of light. By splitting the star's light into a rainbow spectrum, astronomers can detect those sections of missing light and determine what molecules are in the planet's atmosphere.

For these observations, the project team sel ected WASP-79b, a Jupiter-sized planet located about 780 light-years from Earth. The team expects to detect and measure the abundances of water, carbon monoxide, and carbon dioxide in WASP-79b. Webb also might detect new molecules not yet seen in exoplanet atmospheres.

Phase curve – A weather map

Planets that orbit very close to their stars tend to become tidally locked. One side of the planet permanently faces the star while the other side faces away, just as one side of the Moon always faces the Earth. When the planet is in front of the star, we see its cooler backside. But as it orbits the star, more and more of the hot day-side comes into view. By observing an entire orbit, astronomers can observe those variations (called a phase curve) and use the data to map the planet's temperature, clouds, and chemistry as a function of longitude.

https://www.youtube.com/watch?time_continue=1&v=Ppc1N3k8pYY
This animation describes how Webb will use transmission spectroscopy to study the atmospheres of distant exoplanets.
Credits: NASA, ESA, CSA, and L. Hustak (STScI)

The team will observe a phase curve of the "hot Jupiter" known as WASP-43b, which orbits its star in less than 20 hours. By looking at different wavelengths of light, they can sample the atmosphere to different depths and obtain a more complete picture of its structure. "We have already seen dramatic and unexpected variations for this planet with Hubble and Spitzer. With Webb we will reveal these variations in significantly greater detail to understand the physical processes that are responsible," said Bean.

Eclipse – A planet's glow

The greatest challenge when observing an exoplanet is that the star's light is much brighter, swamping the faint light of the planet. To get around this problem, one method is to observe a transiting planet when it disappears behind the star, not when it crosses in front of the star. By comparing the two measurements, one taken when both star and planet are visible, and the other when only the star is in view, astronomers can calculate how much light is coming from the planet alone.

This technique works best for very hot planets that glow brightly in infrared light. The team plans to study WASP-18b, a planet that is baked to a temperature of almost 4,800 degrees Fahrenheit (2,900 K). Among other questions, they hope to determine whether the planet's stratosphere exists due to the presence of titanium oxide, vanadium oxide, or some other molecule.

Habitable planets

Ultimately, astronomers want to use Webb to study potentially habitable planets. In particular, Webb will target planets orbiting red dwarf stars since those stars are smaller and dimmer, making it easier to tease out the signal fr om an orbiting planet. Red dwarfs are also the most common stars in our galaxy.

"TESS should locate more than a dozen planets orbiting in the habitable zones of red dwarfs, a few of which might actually be habitable. We want to learn whether those planets have atmospheres and Webb will be the one to tell us," said Kevin Stevenson of the Space Telescope Science Institute, a co-principal investigator on the project. "The results will go a long way towards answering the question of whether conditions favorable to life are common in our galaxy."

The James Webb Space Telescope will be the world's premier space science observatory. Webb will solve mysteries of our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international project led by NASA with its partners, the European Space Agency (ESA) and the Canadian Space Agency (CSA).

By Christine Pulliam
Space Telescope Science Institute, Baltimore, Md.
[свернуть]
Last Updated: July 11, 2018
Editor: Lynn Jenner

tnt22

https://www.nasa.gov/image-feature/goddard/2018/technicians-ensure-james-webb-space-telescope-s-sunshield-survives-stresses
ЦитироватьJuly 18, 2018

Technicians Ensure James Webb Space Telescope's Sunshield Survives Stresses Experienced During Liftoff


​Image credit: Northrop Grumman

The sound associated with a rocket launch creates extreme vibrations that can adversely affect any satellite or observatory, so engineers put spacecraft through simulations to ensure they will remain operational.

In this photo, technicians delicately inspect stowed sunshield membranes of NASA's James Webb Space Telescope on the forward side of the spacecraft. Acoustic testing exposes the spacecraft to similar forces and stress experienced during liftoff, allowing engineers to better prepare it for the rigors of spaceflight.
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The sunshield separates the observatory into a hot, sun-facing side (reaching temperatures close to 230 degrees Fahrenheit), and a cold side (approximately minus 400 degrees Fahrenheit) where the sunlight is blocked from interfering with the sensitive telescope instruments.

The James Webb Space Telescope will be the world's premier space science observatory. Webb will solve mysteries of our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international project led by NASA with its partners, the European Space Agency (ESA) and the Canadian Space Agency (CSA).
[свернуть]
Last Updated: July 18, 2018
Editor: Lynn Jenner

tnt22

https://www.nasa.gov/image-feature/goddard/2018/technicians-lay-nasas-webb-sunshield-layers-flat-for-inspection
ЦитироватьJuly 20, 2018

Technicians Lay NASA's Webb Sunshield Layers Flat for Inspection



Technicians and engineers working to ensure the soundness of NASA's James Webb Space Telescope manually lower its folded sunshield layers for easier access and inspection. After being lowered, engineers thoroughly inspect all five layers of the reflective silver-colored sunshield for any issues that may have occurred as a result of acoustic testing.

Acoustic testing exposes the spacecraft to similar forces and stress experienced during liftoff, allowing engineers to better prepare it for the rigors of spaceflight.
Спойлер
The sunshield separates the observatory into a hot, sun-facing side (reaching temperatures close to 230 degrees Fahrenheit), and a cold side (approximately minus 400 degrees Fahrenheit) where the sunlight is blocked from interfering with the sensitive telescope instruments.

The James Webb Space Telescope will be the world's premier space science observatory. Webb will solve mysteries of our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international project led by NASA with its partners, the European Space Agency (ESA) and the Canadian Space Agency (CSA).

​Image credit: Northrop Grumman

By Thaddeus Cesari
NASA's Goddard Space Flight Center
[свернуть]
Last Updated: July 20, 2018
Editor: Lynn Jenner

tnt22

ЦитироватьNASA's Most Scientifically Complex Space Observatory Requires Precision

NASA Goddard

Опубликовано: 25 июл. 2018 г.

The James Webb Space Telescope is one the most ambitious, and technically complex missions NASA has ever set its focus on. Building an infrared observatory of this magnitude, power and complexity has never been attempted before. In order to ensure seamless operation in space, the cutting-edge technology incorporated into Webb must be rigorously tested prior to launch.
https://www.youtube.com/watch?v=6zNsc0e3Znshttps://www.youtube.com/watch?v=6zNsc0e3Zns (3:26)

tnt22

ЦитироватьWebb - A Tale of Precise Construction

James Webb Space Telescope (JWST)

Опубликовано: 26 июл. 2018 г.

The James Webb Space Telescope is one the most ambitious, and technically complex missions NASA has ever set its focus on. Building an infrared observatory of this magnitude, power and complexity has never been attempted before. In order to ensure seamless operation in space, the cutting-edge technology incorporated into Webb must be rigorously tested prior to launch.

The entire design of the Webb took years to develop, and was specifically engineered to see more of the cosmos than ever before. It required hundreds of scientists, engineers, optics experts and many others to pool their knowledge in a way that had never been done. Relying on the teamwork of three prominent space agencies: NASA, the European Space Agency, and the Canadian Space Agency, Webb has come to include over 1,200 people worldwide to bring the world's newest and most powerful infrared observatory to life.
https://www.youtube.com/watch?v=-MFFgeJ1gEIhttps://www.youtube.com/watch?v=-MFFgeJ1gEI (1:12)

tnt22

ЦитироватьNorthrop Grumman‏Подлинная учетная запись @northropgrumman 10 ч. назад

The @NASAWebb hardware is 100% complete. Both halves of the telescope are under one roof at our Redondo Beach, CA, facility. #Webb is in the integration and testing phase, moving steps closer to revealing the mysteries of the universe. Learn more: http://ms.spr.ly/6013r47dZ 



tnt22

ЦитироватьJWST: a beacon for science

European Space Agency, ESA

Опубликовано: 31 июл. 2018 г.

Astronomers all over the world are eagerly awaiting the launch of the James Webb Space Telescope. The infrared space telescope, which will carry the largest astronomical mirror ever flown in space is one of the most complex observatories ever built. It will allow unprecedented science, including investigations into the atmospheres of exoplanets and the formation of galaxies, addressing fundamental questions in astronomy. The mission is an international collaboration between NASA, ESA and the Canadian Space Agency, and is planned for launch in 2021 on a European Ariane 5 rocket.
https://www.youtube.com/watch?v=7YvRQ5wT8c4https://www.youtube.com/watch?v=7YvRQ5wT8c4 (3:54)

tnt22

https://spacenews.com/senate-science-hearing-debates-effectiveness-of-decadal-surveys/
ЦитироватьSenate science hearing debates effectiveness of decadal surveys
by Jeff Foust — August 2, 2018


Witnesses at an Aug. 1 hearing said that while the decadal survey process is useful for identifying priorities for NASA science missions, like the James Webb Space Telescope, some argued for improvements. Credit: NASA

WASHINGTON — A Senate hearing Aug. 1 intended to discuss NASA's search for life beyond Earth turned into a discussion about the long-standing process the scientific community uses to prioritize missions.
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The hearing by the Senate's space subcommittee on "The Search for Life: Utilizing Science to Explore our Solar System and Make New Discoveries" featured witnesses fr om within and outside the agency to discuss astrobiology research regarding other worlds in the solar system and on distant exoplanets.

The hearing was the second in a series planned by the committee to examine issues to go into a future NASA authorization bill. "What do you see as the science-related priorities that are most important to be reflected in that bill?" asked subcommittee chairman Sen. Ted Cruz (R-Texas) during the hearing.

One of the witnesses, David Spergel, a professor of astronomy at Princeton University and former chair of the Space Studies Board, mentioned the decadal survey process used in astrophysics and other disciplines, where scientists identify the top research priorities in their field and potential missions, from small to large, that should be flown in support of those priorities.

He noted that the astrophysics community was preparing to start work on its next decadal survey, due to be completed in late 2020. "We'll begin by thinking about what are the key driving questions. The search for life will almost certainly be one," he said. "Others will include understanding the processes of galaxy formation, star formation and the emergence of structure."

Sen. Ed Markey (D-Mass.), ranking member of the subcommittee, raised the question of prioritizing missions again later in the hearing. Another witness, Sara Seager, a professor of physics and planetary science at the Massachusetts Institute of Technology, suggested it was worth reconsidering how the decadal process works.

"It's kind of the structure that we're, let's say, forced to abide by," she said. "Any institution, any kind of structure, that's been around for more than half a century should be reviewed to see if it's still effective."
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She said she thought there were "many areas for room for improvement" in the decadal process. Asked for specifics, she argued that the current process leads to mission concepts that are "very complicated" and thus expensive, like the James Webb Space Telescope. There may be a case, she said, for more focused missions that, while still large, do not attempt to be all things for all astronomers. "We can't really do that in the current formulation of the survey," she said.

How the decadal survey is organized makes it difficult for younger scientists to make their voices heard, she added. "Sometimes the younger people know more."

Spergel and other witnesses, though, defended the decadal survey process while agreeing it can be improved. "The decadal process has been an effective way for prioritization," he said. "It's a process that can be and is being improved." One such improvement, he said, is doing a better job of defining proposed missions and estimating their cost before recommending them, citing the experience with JWST.

"I think it's an important and strong process that needs to be adhered to, because it really allows the best science to come forward," said Ellen Stofan, former NASA chief scientist and current director of the National Air and Space Museum. "It's not the person who shouts the loudest or has the most connections. It really is the best science."

Thomas Zurbuchen, NASA associate administrator for science, said he welcomed the guidance provided by the decadal surveys. "For me, the decadal has been a very successful activity, but like every human endeavor, it should always be questioned and should be improved as we go forward," he said. Seager's concerns on issues like diversity of inputs during the decadal process "resonated" with him, he said.

That discussion of the decadal process was one of several topics touched upon during the 80-minute hearing officially about the search for life beyond Earth. Senators asked questions on other topics, ranging from planetary defense against near Earth asteroids to space weather to the importance of NASA continuing to perform Earth science research.

The hearing also briefly discussed the latest cost and schedule overruns with JWST. Unlike the House Science Committee, which spent several hours on the topic in a two-part hearing July 25 and 26, the Senate space subcommittee spent only a few minutes about it, with Cruz asking the witnesses to explain "that incredible increase" in its costs.

"That's the question I'm asking myself and my team on a regular basis," Zurbuchen responded. He blamed the increase on several issues, including "excessive optimism," and development of multiple new technologies, and additional time needed to complete integration and testing work for the spacecraft.

Asked by Cruz if JWST's delays would lead to a reassessment of the use of cost-plus versus fixed-price contracting, Zurbuchen argued complex missions like JWST would not fit well in a fixed-price approach. "For new, innovative projects of the type that nobody has ever done, it will be very hard to get a fixed-price contract from a company," he said.

Spergel, in his opening statement, asked Congress to spread out the additional cost incurred by JWST's delays across the agency, versus simply the astrophysics program. "JWST's delays are frustrating for all of us," he said, but said the mission will ultimately be "a flagship of all of NASA" with its scientific discoveries.

"Since JWST is an agency-wide priority, new costs should be spread across the agency," he said. "If they're borne entirely by the astrophysics directorate, they'll have a devastating effect on future missions and the scientific program."

Spergel and others said that JWST and NASA's next large astrophysics mission, the Wide-Field Infrared Survey Telescope, offered national leadership at a time when Europe and especially China are developing new capabilities that could soon rival the U.S.

"I think we are leading the world," he said. "I have been very impressed by the investments the Chinese are making in space science. They were really not even significant players 10 years ago. Looking to wh ere they might be a decade from now, if we stop investing, they will be the leaders."

Димитър


tnt22

ЦитироватьGrant Tremblay‏ @astrogrant 3 ч. назад

.@NASAWebb @stsci Cycle 1 GO deadline now ~March 2020 at earliest
ЦитироватьJane Rigby‏ @janerrigby 22 авг.

Timeline for JWST cycle 1 proposals. #iau2018


tnt22

https://www.nasa.gov/image-feature/goddard/2018/the-gloo-behind-james-webb-space-telescopes-spider-technology
ЦитироватьAug. 22, 2018

The 'Gloo' Behind James Webb Space Telescopes Spider Technology



It takes a team of talented individuals working in unison to brainstorm, build and deliver what will become the world's most powerful space telescope. Marcelino Sansebastian is a Senior Instrument Technician at NASA's Goddard Space Flight Center in Greenbelt, Maryland who has been deeply involved with NASA's James Webb Space Telescope since the project began. Known for his passion, skillset and unique nickname 'Gloo',  Sansebastian has had his hand in helping design and invent a long list of mission-critical components that have flown to space over the last 30 years.

Even though it is already quite cold in outer space, one of the four instruments aboard the Webb telescope known as MIRI (Mid-Infrared Instrument) requires additional cooling to bring it to an even more frigid operating temperature of approximately minus 450°F (minus 266°C). If you are looking for heat signatures, and that's what Webb's instruments will be doing, the instruments themselves have to be incredibly cold, so they are intentionally cooled down so their sensors can more readily detect faint thermal signatures.
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The hyper-sensitive detectors on MIRI will allow it to see light fr om distant galaxies, newly forming stars, faintly visible comets, as well as objects in the Kuiper Belt - a vast rim of primordial debris encircling our solar system. MIRI's optics will provide wide-field, broadband imaging that will continue the breathtaking astrophotography that has made the Hubble Space Telescope so universally admired.

Aptly named a 'Spider' for its eight thermally isolating Kevlar fibers and coiled shock reducing legs, the device pictured here is designed to securely guide small cooling and exhaust tubes throughout the observatory. As a mission-critical component, the Spiders that have been installed on Webb were built by a technician who as a child, had dreamed of working for NASA.

"I always thought rockets were neat when I was younger, and was always looking up at the stars. One night when I was 10 years old, my Uncle Paco woke me up while we were in this little village in the middle of Spain. He said 'Follow me, get dressed - we are going somewh ere.' We then walked down this long dark dusty path in the middle of the night, and stepped into this small house that had the only television around. He knew somehow that it was important for me to see the first humans landing on the Moon, live as it happened... Because of that I always thought and dreamed about working for NASA"

Before technicians like Sansebastian could begin assembling the telescope, certain inventions like these "spiders" needed to be custom built to empower Webb to begin its search for untold cosmic wonders. These enabling technologies are at the forefront of human capability and have only recently become available for space missions, and are in-part why Webb will far surpass its predecessors.

"I think the most impressive thing about the James Webb Space Telescope is that we are taking all these different and incredibly complicated components made from all these exotic materials, and assembling them into one functioning unit. Exposing it to the rigors of launch, and extreme temperatures found in space and then commanding it to deploy in a long series of ballet-inspired movements. To me, it's mind blowing."

The James Webb Space Telescope will be the world's premier space science observatory. Webb will solve mysteries of our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international project led by NASA with its partners, the European Space Agency (ESA) and the Canadian Space Agency (CSA).
[свернуть]
By Thaddeus Cesari
NASA Goddard Space Flight Center


Photo credit: NASA/Chris Gunn

Last Updated: Aug. 22, 2018
Editor: Lynn Jenner

tnt22

https://www.nasa.gov/feature/goddard/2018/success-in-critical-communications-tests-for-nasas-james-webb-space-telescope
ЦитироватьSept. 5, 2018

Success in Critical Communications Tests for NASA's James Webb Space Telescope

When NASA's James Webb Space Telescope launches in 2021, it will write a new chapter in cosmic history. This premier space science observatory will seek the first stars and galaxies, explore distant planets around other stars, and solve mysteries of own solar system. Webb will be controlled fr om the Mission Operations Center (MOC) at the Space Telescope Science Institute in Baltimore, Maryland.


The Mission Operations Center for the James Webb Space Telescope is located at the Space Telescope Science Institute in Baltimore, Md. In preparation for launch, the flight operations team recently conducted two critical and successful communications tests.
Credits: STScI

To prepare for launch, the flight operations team recently conducted two successful communications tests. The first simulated the complex communications among numerous entities in the critical period of launch through the first six hours of flight. The second demonstrated that the MOC could successfully communicate with the telescope.
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A Complicated Dance

Fr om the moment Webb launches, and through the first six hours of flight, five different telecommunications service providers located around the world will alternately convey command and telemetry data to the mission operations team in the MOC. The first exercise demonstrated the complex exchange among these facilities.

These different providers are needed because of the geometry of Earth in relation to Webb's orbit and altitude. "Whereas most low-Earth missions can use TDRS (Tracking and Data Relay Satellite) or some other kind of communications satellite in orbit around Earth to relay data, we are so far away that we have to use other facilities," explained NASA's Carl Starr, the Mission Operations Manager, or "MOM," for Webb at NASA's Goddard Space Flight Center, Greenbelt, Maryland.

By six hours after liftoff, Webb will be about halfway to the Moon and six times higher in altitude than the geosynchronous Earth orbit (GEO) where TDRS and many communications satellites dwell. When the telescope reaches its destination, it will be nearly a million miles from Earth—about 45 times farther away than GEO.

"It's a lot of going back and forth," said Starr. "You have to change configurations, you need a stable connection with Webb at each change, you have to establish the network connections, you have to process the data—and you have to do it multiple times with different stations and make it seamless."

"And to make things even more complicated," Starr continued, "everyone we are talking about is in different places. You have the Space Network out in New Mexico, the Deep Space Network in California, and the European Space Agency's Malindi station in Kenya and European Space Operations Centre in Germany. It becomes a very complicated test to do, because no one is in the same time zone—and all of that data comes in and out of this building."

This test was a major step in demonstrating the flight operations capabilities and processes to support launch-day communications. After the first day, the team moves to a normal setup with just the three Deep Space Network terminals around the world.

"The teams were able to talk with the external entities, and prove the concept that we can manipulate the communications on the day of launch here in the building for the mission," Starr said. "We'll have other proficiency exercises later, but this was the first time that we did it, and it was very successful."

https://www.youtube.com/watch?v=aKL1eQeUBQI
(video 0:15)
Flight controllers in the Mission Operations Center follow detailed checklists and procedures as they simulate operation of the James Webb Space Telescope.
Credits: M. Estacion (STScI)

Talking to the Telescope

No mission would be possible without communicating with the telescope. The flight operations team in Baltimore recently did that for the first time, talking to the actual Webb spacecraft on the ground while it's being integrated and tested across the country at the Northrop Grumman facility in Los Angeles, California.

"We treated Webb as if it were a million miles away," said Starr. To do this, the flight operations team connected the spacecraft to the Deep Space Network. However, since Webb isn't really 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 flies.

"We can command and control the vehicle now, and run tests with it from here, without having to travel to Northrop Grumman," Starr explained. "It really is making use of technology to stay on schedule."

It didn't really matter wh ere Webb was during the test. "As far as we're concerned, it could be in the basement of this building, and we wouldn't know any different," Starr added. "You're just at your console, you've got a data line, your screen...it's all very much remote. I could imagine it must be how drone pilots feel. They're not anywhere near wh ere their vehicle is."

During the exercise, the team executed non-operational commands and initiated a recorder playback. This important test demonstrated the flight operations team's ability to command Webb from the MOC in Baltimore.

Throughout most of commissioning, the MOC will be in constant communication with Webb. After commissioning, approximately 180 days after launch, the team will communicate for 8 hours a day with the telescope. During that time, operators will send up packages of commands for the telescope to run autonomously and downlink the science data.

More to Come

More tests will follow, but these were the first to show the MOC's successful communication with Webb and with the many command and telemetry service providers. The fact that these exercises were carried out flawlessly is a testament to the hard work of the flight operations team, as well as teams across the country and around the world.

The James Webb Space Telescope will be the world's premier space science observatory. Webb will solve mysteries of our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international project led by NASA with its partners, the European Space Agency (ESA) and the Canadian Space Agency (CSA).

By Ann Jenkins
Space Telescope Science Institute, Baltimore, Md.
[свернуть]
Last Updated: Sept. 5, 2018
Editor: Lynn Jenner