JWST – Ariane 5 ECA – Kourou ELA-3 – 31.10.2021

Автор zandr, 28.03.2018 21:09:50

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zandr

28.03.2018 21:09:50 Последнее редактирование: 27.07.2020 23:00:21 от zandr
Предыстория в теме Best Telescope:Телескоп Гершель,OWL, JWST, greatest views,  начиная с поста #348 

Если кто-то считает свои посты о сабже в той теме весьма существенными - предлагаю перенести сюда.

zandr

http://tass.ru/kosmos/5072992
ЦитатаNASA перенесло запуск нового телескопа на май 2020 года
ВАШИНГТОН, 28 марта. /ТАСС/. Национальное управление США по аэронавтике и исследованию космического пространства (NASA) в очередной раз отсрочило вывод на орбиту нового телескопа James Webb. Теперь, как объявил во вторник исполняющий обязанности главы ведомства Роберт Лайтфут, обсерваторию планируется отправить в космос в мае 2020 года - на год позже, чем предполагалось.

© NASA/Desiree Stover
ВАШИНГТОН, 28 марта. /ТАСС/. Национальное управление США по аэронавтике и исследованию космического пространства (NASA) в очередной раз отсрочило вывод на орбиту нового телескопа James Webb. Теперь, как объявил во вторник исполняющий обязанности главы ведомства Роберт Лайтфут, обсерваторию планируется отправить в космос в мае 2020 года - на год позже, чем предполагалось.
"Работа над всеми основными компонентами телескопа завершена, однако некоторые проявившиеся во время их испытаний проблемы вынуждают нас пересмотреть сроки запуска", - отметил он на пресс-конференции в штаб-квартире NASA, которая транслировалась на сайте ведомства.
По словам помощника директора NASA Томаса Зурбукена, создатели телескопа "недооценили технологическую сложность" данного проекта. "Процесс сборки и испытаний отдельных компонентов занял больше времени, чем ожидалось", - пояснил он. К тому же при проверке работоспособности уникального солнцезащитного экрана размером с теннисный корт обнаружились разрывы длиной до 10 см в полиамидной пленке.
"У нас есть только один шанс сделать все правильно до того, как аппарат будет выведен в космос", - отметил Зурбукен. Производить ремонтные работы на орбите, как это делалось в случае с обсерваторией Hubble, будет невозможно хотя бы потому, что в распоряжении NASA уже нет шаттлов, подчеркнул он.
Лайтфут счел необходимым обратить внимание на то, что дополнительные испытания и перенос запуска могут привести к росту стоимости проекта. Конгресс США в 2001 году установил планку расходов на создание телескопа без учета средств, необходимых непосредственно для запуска, в размере $8 млрд. NASA уже вложило в реализацию проекта $7,3 млрд, отметил и. о. директора. "Превышение предела расходов потребует от Конгресса принятия решения о дополнительном финансировании", - сказал Лайтфут, обещав представить законодателям летом детальный отчет о графике работ и предполагаемых затратах.
Поиск экзопланет
Телескоп, названный в честь Джеймса Уэбба, руководителя программы "Аполлон", позволившей человеку побывать на Луне, должен заменить на орбите Hubble. Первоначально предполагалось, что это произойдет в 2013 году, но конструкторские работы сильно отстали от графика. Лишь в ноябре 2016 года завершилась сборка основных сегментов James Webb и было объявлено, что специалисты NASA теперь приступают к их наземным испытаниям с тем, чтобы вывести на орбиту в октябре 2018 года. В конце сентября прошлого года запуск был перенесен на март-июнь 2019 года.
На обсерватории установлено зеркало диаметром 6,5 м. Ее предполагается вывести далеко за Луну, на орбиту, находящуюся на расстоянии примерно 1,6 млн км от поверхности Земли. Ракету-носитель Ariane 5 обещали предоставить европейцы, равно как и свой космодром Куру во Французской Гвиане.
James Webb будет изучать древнейшие во Вселенной звезды и галактики, сформировавшиеся после Большого взрыва, а также заниматься поиском потенциально пригодных для жизни планет. Расчетный срок его эксплуатации составляет 10 лет.

tnt22

http://spacenews.com/jwst-suffers-new-problem-during-spacecraft-testing/
ЦитатаJWST suffers new problem during spacecraft testing
by Jeff Foust -- May 3, 2018


The optical element of NASA's James Webb Space Telescope is removed from a shipping container in a Northrop Grumman clean room in March. The spacecraft element, including the folded-up sunshield, is at left prior to undergoing acoustic testing. Credit: Northrop Grumman

WASHINGTON -- As an independent review of NASA's James Webb Space Telescope continues, the project is dealing with a new problem discovered in recent testing of the spacecraft.

In a presentation at a meeting of the National Academies' Space Studies Board here May 3, Greg Robinson, the JWST program director at NASA Headquarters, said some "screws and washers" appear to have come off the spacecraft during recent environmental testing at a Northrop Grumman facility in Southern California.

Technicians found the items after the spacecraft element of JWST, which includes the bus and sunshield but not its optics and instruments, was moved last weekend from one chamber for acoustics tests to another to prepare for vibration testing.
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"Right now we believe that all of this hardware -- we're talking screws and washers here -- come from the sunshield cover," he said. "We're looking at what this really means and what is the recovery plan." The problem, he said, was only a couple of days old, and he had few additional details about the problem.

"It's not terrible news, but it's not good news, either," he said.

The incident, Robinson argued, showed the importance of the wide range of tests the spacecraft is put through prior to launch. "That's why we do the testing," he said. "We do it now, we find it now, we fix it and we launch a good spacecraft."

This latest incident comes as an independent review board, chartered by NASA in late March after announcing a one-year delay in JWST's launch because of other technical issues, is in the midst of its analysis of the mission and its launch readiness. That review, led by retired aerospace executive and former NASA Goddard director Tom Young, is scheduled to be completed at the end of the month.

"It was a no-brainer to put an independent review board in place," Thomas Zurbuchen, NASA associate administrator for science, said at the Space Studies Board meeting May 2. The board, he said, will provide an independent look at the status of the mission and identify what needs to be done to ensure the mission will be successful.

Zurbuchen said there would be a "little bit of a pause" after the board delivers its final report, in part because of a prior commitment by Young in early June that makes him unavailable for discussions about the report or additional work. He said NASA will start briefing Congress and others about the report, and the agency's response, in late June.

That report will allow NASA to refine a launch date of approximately May 2020 that it announced March 27. Robinson believed there was margin in the revised development schedule to maintain that date. "We believe we have good margin there, and a lot that margin is for things like we just experienced," he said. "I still believe we'll go in 2020, in roughly the same timeframe that we talked about, unless this problem takes longer than we expect."

One lesson already learned, he said, was the need for more NASA oversight of Northrop Grumman's work. "We had people in the plant for a long time, four or five people," he said. "We've added a lot of folks in the past five or six months for oversight at Northrop Grumman."

tnt22

https://www.nasa.gov/feature/nasa-s-webb-observatory-spacecraft-element-environmental-testing-update
ЦитатаMay 4, 2018

NASA's Webb Observatory Spacecraft Element Environmental Testing Update

The spacecraft element of NASA's James Webb Space Telescope recently completed its first two major launch environmental tests at Northrop Grumman Aerospace Systems in Redondo Beach, California, and will soon undergo further tests to ensure it will handle the rigors of launch and the harsh environment of space.
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The James Webb Space Telescope's spacecraft element undergoing acoustic testing.
Credits: NASA/Chris Gunn


The spacecraft element's first test simulated the mechanical shock caused by the separation of the spacecraft's payload adapter after launch. The second test subjected the spacecraft to the extreme sound and resultant vibration of the launch environment. These shock separation and acoustics tests are routine for all spacecraft.

Detailed inspections of the hardware after the acoustic test showed that fastening hardware that hold the sunshield membrane covers in place had come loose.

"NASA is reviewing options for repair and the next steps in spacecraft element launch environment testing," said Greg Robinson, Webb's program director. "The team is reviewing the test data and hardware configuration and is actively working towards corrective action in the near future. We expect to get back to the environmental test flow shortly and continue to move safely and methodically toward mission success."

Discoveries like this one are not uncommon in the development of a complex and unique spacecraft. "This is an example of why space systems are thoroughly and rigorously tested on the ground to uncover imperfections and fix them prior to launch," said Robinson.

Webb's spacecraft element is the observatory's combined sunshield and spacecraft bus. The spacecraft element and Webb's combined optical element and science instruments, called its science payload, will form the complete observatory. The two halves currently reside at Northrop Grumman, NASA's observatory contractor.

The shock of payload separation

When Webb is launched into space, it must be folded like origami to fit inside its Ariane 5 rocket's payload fairing, which is about 15.1 feet (4.6 meters) wide. The fairing, also called the rocket's nose cone, protects Webb fr om the forces and heat of the atmosphere as the rocket accelerates into space.

Inside the fairing, the payload adapter physically attaches Webb to the top of the Ariane 5. The adapter has two halves -- one that is permanently attached to Webb and the other that is attached to the second stage of the rocket. When the rocket reaches a specific altitude in Earth's upper atmosphere, the payload fairing is jettisoned and falls back to Earth. Following this, the first stage of the Ariane 5 expends its fuel and also is jettisoned.

After the second stage of the rocket gives Webb a final nudge to send it on its way to its orbit at the second Sun-Earth Lagrange point (L2), the two halves of the payload adapter separate, releasing Webb from the rocket. The release sends a mechanical shock -- a series of high-frequency vibrations -- through the observatory.

"Mechanical shock is a quick jolt to the system, a lot like when you shut your car door and the car shudders a little," explained Keith Parrish, the Observatory Manager for Webb at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The electronics in Webb are designed to withstand this shock just as a laptop is designed to withstand the bangs and drops of everyday life.

To simulate this separation on Earth, engineers at Northrop Grumman first suspended the spacecraft element in the air with the payload adapter attached to it. They then remotely released the bottom half of the payload adapter, which is the half that will be attached to the rocket during launch. The bottom half fell approximately 8 inches (about 20 centimeters) onto a padded catch area on the floor of the cleanroom wh ere the test was being performed.

The engineers monitored the forces caused by the release to ensure they were within expected values, and high-speed video cameras recorded the separation to make sure it was smooth. During the actual flight and separation, 12 springs will gently push Webb away from the Ariane 5.

The sound and vibration of launch

After completing shock testing, engineers enveloped the spacecraft in a plastic tent and moved it into Northrop Grumman's Large Acoustic Test Facility. The tent protected the spacecraft from contamination during the move and during the acoustic test.

During the test, engineers subjected the spacecraft element to sound frequencies ranging from 25 Hertz to 2,500 Hertz, which is what Webb will experience during launch. These frequencies range from low bass (similar to that of a kick drum) to low treble (about the same level as the E7 key on a piano). It was also tested at loudness levels up to 142.5 decibels, about 3 decibels higher than what is expected during launch. Webb's science payload went through a similar acoustic test at NASA's Goddard Space Flight Center in Greenbelt, Maryland, in 2017.

Engineers mounted several microphones inside and outside the tent to monitor the acoustic environment during testing. They also mounted about 500 accelerometers around the spacecraft element to monitor the vibrational responses it experienced. An accelerometer measures the forces or stress the hardware is experiencing during the test.

After this first series of tests, Webb's spacecraft element will undergo vibration testing to ensure it will survive the intense shake of launch.

***
NASA's James Webb Space Telescope will be the world's next great 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 ESA (European Space Agency) and the Canadian Space Agency.

Part of the ESA's contribution is the Ariane 5 launch vehicle, which is operated by Arianespace. Arianespace subcontractor RUAG Space provided the rocket's payload adapter.

For more information about Webb, visit: www.nasa.gov/webb

By Eric Villard
NASA's Goddard Space Flight Center, Greenbelt, Md.
Last Updated: May 4, 2018
Editor: Sarah Loff

zandr

http://tass.ru/kosmos/5180549
ЦитатаСМИ: NASA столкнулось с новыми техническими проблемами при сборке телескопа James Webb
ВАШИНГТОН, 7 мая. /Корр. ТАСС Александр Пахомов/. Американское космическое ведомство - NASA столкнулось с новыми техническими проблемами, возникшими при сборке и испытаниях основных компонентов телескопа James Webb. Об этом сообщил в воскресенье на своем сайте еженедельник SpaceNews.
По его данным, руководитель проекта создания James Webb в штаб-квартире NASA Грег Робинсон на встрече с членами Совета по космическим исследованиям Национальной академии наук США 3 мая рассказал о том, что во время перемещения в конце апреля из одного цеха в другой уникального солнцезащитного экрана телескопа из него выпало несколько "болтов и шайб".
Произошло это на предприятии аэрокосмической корпорации Northrop Grumman в Редондо-Бич (штат Калифорния), где и производится сейчас окончательная сборка телескопа. Болты и шайбы были обнаружены техниками на полу помещения после доставки огромного экрана из акустической камеры в цех для подготовки к вибрационным испытаниям. "Мы пытаемся сейчас оценить, какие нам необходимо будет предпринять в этой связи шаги, - заметил Робинсон. - Это, конечно, не ужасное известие, но и ничего хорошего тоже нет".
Как считает руководитель проекта, случившееся служит еще одним доказательством важности проведения всесторонних испытаний компонентов телескопа. "Мы проводим испытания, находим недостатки, исправляем их и отправляем в космос хороший аппарат", - указал он.
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Ранее при проверке работы солнцезащитного экрана размером с теннисный корт - это пять слоев полиамидной пленки, каждая толщиной с человеческий волос, - обнаружились разрывы в этих пленках длиной до 10 см. А ведь он призван защищать основную аппаратуру телескопа от перегрева под воздействием солнечных лучей.
Отсрочка за отсрочкой
Телескоп, названный в честь Джеймса Уэбба, руководителя программы "Аполлон", позволившей человеку в 1960-х - 1970-х годах побывать на Луне, должен заменить на орбите ныне действующую обсерваторию Hubble. Первоначально предполагалось, что это произойдет в 2013 году, но конструкторские работы сильно отстали от графика. Лишь в ноябре 2016 года завершилась сборка основных сегментов James Webb, и было объявлено, что специалисты NASA теперь приступают к их наземным испытаниям с тем, чтобы вывести на орбиту в октябре 2018 года. В конце сентября прошлого года запуск был отсрочен на март-июнь 2019 года.
А 27 марта с.г. NASA в очередной раз перенесло старт миссии - теперь на май 2020 года. "Работа над всеми основными компонентами телескопа завершена, но некоторые проявившиеся во время их испытаний проблемы вынуждают нас пересмотреть сроки запуска", - указал тогда исполняющий обязанности директора ведомства Роберт Лайтфут. Как пояснил, в свою очередь, помощник директора NASA, ответственный за научные миссии, Томас Зурбукен, создатели телескопа "недооценили технологическую сложность" данного проекта.
"У нас есть только один шанс сделать все правильно до того, как аппарат будет выведен в космос", - добавил Зурбукен. Производить ремонтные работы на орбите, как это делалось в случае с Hubble, будет невозможно потому, что в распоряжении NASA уже нет шаттлов, заметил он. К тому же, если Hubble кружит на орбите высотой 565 км, то James Webb предполагается вывести далеко за Луну в точку Лагранжа, находящуюся на расстоянии примерно 1,6 млн км от поверхности Земли.
Лайтфут счел необходимым обратить внимание на то, что дополнительные испытания и перенос запуска могут привести к росту стоимости проекта. Конгресс США в 2001 году установил планку расходов на создание телескопа без учета средств, необходимых непосредственно для запуска, в размере $8 млрд. NASA уже вложило в реализацию проекта $7,3 млрд. "Превышение предела расходов потребует от Конгресса принятия решения о дополнительном финансировании", - сказал он.
Будет искать экзопланеты
На телескопе James Webb установлено зеркало диаметром 6,5 м. Зеркальная решетка телескопа состоит из 18 секций, каждая из которых имеет форму равностороннего шестиугольника и весит около 40 кг. Для их производства был выбран бериллий - материал, устойчивый к сверхнизким температурам. Главному модулю обсерватории, где размещены оптические приборы и инфракрасные датчики, предстоит функционировать в открытом космосе при температуре примерно минус 233 градуса Цельсия.
Ракету-носитель Ariane 5 пообещали предоставить европейцы, равно как и свой космодром Куру во Французской Гвиане.
После вывода в космос вся бортовая аппаратура телескопа будет проверена в течение 6 месяцев, и James Webb приступит к изучению древнейших во Вселенной звезд и галактик, сформировавшихся после Большого взрыва, а также займется поиском потенциально пригодных для жизни планет. Основываясь на информации, полученной с помощью Hubble и других телескопов, эксперты NASA высказывают предположение, что только в галактике Млечный путь, в которой расположена наша Солнечная система, имеется по меньшей мере 11 млрд планет, сравнимых по размеру с Землей. С 1995 года было подтверждено существование 3,5 тыс. экзопланет, на которых потенциально возможна жизнь, и насчитывается еще около 4 тыс. "кандидатов".
Срок эксплуатации телескопа рассчитан на 10 лет.

tnt22

ЦитатаNASA Webb Telescope‏Подлинная учетная запись @NASAWebb 21 мин. назад

In this photo, Paloma Rubio of @northropgrumman installs thermal blankets on #Webb. Read more about the clever technique used to attach them: https://www.flickr.com/photos/nasawebbtelescope/28145823068/ ... (Hint: it has to do with the extreme environment the telescope will be in.) #JWST

tnt22

ЦитатаNorthrop Grumman‏Подлинная учетная запись @northropgrumman 12 мин. назад

Check out new photos of @NASAWebb #spacecraft element! Photos showcase the #Webb spacecraft bus and sunshield, being lifted and prepped for mechanical shock testing at our facility in Redondo Beach, #California. #JWST #NorthropGrumman #NASA #space #tech #telescope #astronomy


tnt22

691589.pdf - 9.8 MB, 127 стр, 2018-05-07 14:03:36 UTC
Цитата
NASA: Assessments of Major Projects
Government Accountability Office
May 1, 2018

tnt22

https://www.nasa.gov/feature/goddard/2018/engineers-solve-excessive-heat-removal-from-nasa-s-webb-telescope
ЦитатаJune 5, 2018

Engineers Solve Excessive Heat Removal fr om NASA's Webb Telescope

How will NASA's James Webb Space Telescope shed the heat generated by its science instruments and their supporting electronics? To anyone who is not an engineer or scientist, the answer might be complex and "baffling," and it turns out the process is exactly that.
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Engineers reinstall one of the gold-plated baffles that helps direct heat away fr om the integrated science instrument module (ISIM) of NASA's James Webb Space Telescope. The baffles direct the heat generated by the instrument electronics safely into space and away from any cold areas of the infrared telescope.
Credits: NASA/Chris Gunn


Webb's four science instruments are held within a support structure called the integrated science instrument module (ISIM), located behind the telescope's primary mirror. The ISIM and Webb's optics form the science payload of the observatory. To keep heat away from the sensitive instruments, a majority of the electronics used to power and operate the instruments are housed in a compartment below ISIM, wh ere specially designed baffles direct the heat safely into space and away from any cold surfaces of the observatory.


Engineers carefully hold onto a gold-plated baffle as they use a scissor lift to access the back of the integrated science instrument module (ISIM) of NASA's James Webb Space Telescope. They are in the process of reinstalling the baffles, which direct the heat generated by the instrument electronics safely into space and away from any cold areas of the infrared telescope.
Credits: NASA/Chris Gunn


The baffles essentially act as mirrors to reflect the heat (infrared radiation) outward in a specific direction. If that sounds familiar, it is because Webb's mirrors will do very much the same thing -- but instead of reflecting the infrared light into space, they will guide it with pinpoint accuracy to the telescope's science instruments.

"Gold has a very high reflectivity in the infrared spectrum range, so it is ideal for directing heat," explained Matthew Stephens, a mechanical systems engineer for Webb at NASA's Goddard Space Flight Center in Greenbelt, Md. "This is the same reason all of the primary, secondary, and tertiary mirrors are gold-coated."

The engineers in this photo are reinstalling the baffles, which had been previously removed and safely stored in a clean environment to protect them from any contamination during integration and testing of the science payload. The clear plastic sheets placed over the baffles will protect them from any contamination during the remaining integration and testing phases for the observatory.

The engineers had to reinstall the baffles before Webb's science payload and its spacecraft element (the combined spacecraft bus and sunshield) are integrated at Northrop Grumman Aerospace Systems in Redondo Beach, California, wh ere both halves of the observatory currently reside. If the engineers wait until after integration, Webb's tennis-court-sized sunshield will obstruct the ISIM electronics compartment and make reinstalling the baffles much more difficult.

NASA's James Webb Space Telescope will be the world's next great 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 Eric Villard / Rob Gutro
NASA's Goddard Space Flight Center
Last Updated: June 6, 2018
Editor: Lynn Jenner

tnt22

http://www.esa.int/spaceinimages/Images/2018/06/Testing_the_NIRSpec_instrument_on_the_Webb
ЦитатаTESTING THE NIRSPEC INSTRUMENT ON THE WEBB


DOWNLOAD HI-RES JPG (442.65 kB)

DETAILS 

Title Testing the NIRSpec instrument on the Webb
Released 04/06/2018 10:00 am
Copyright ESA/SOT team
Description
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This abstract image is a preview of the instrumental power that will be unleashed once the NASA/ESA/CSA James Webb Space Telescope will be in space.

The image was acquired during testing of the Near-InfraRed Spectrograph (NIRSpec) instrument, which is part of ESA's contribution to the international observatory. NIRSpec will be used to study astronomical objects focussing on very distant galaxies. It will do so by splitting their light into spectra - separating the light into components allows scientists to investigate what these objects are made of.

Created using one of the instrument's internal calibration lamps as the light source, the image shows many spectra as horizontal bands that were recorded by two detectors,. The wavelengths are spread fr om left to right; the pattern of dark stripes, called absorption lines, is characteristic of the light source, much like a fingerprint.

The image was produced by sending commands to open over 100 of the instrument's micro-shutters - minuscule windows the width of a human hair - that will be used to study hundreds of celestial objects simultaneously. The thin strips in the upper and lower parts of the image are spectra created by light that passed through the micro-shutters, while the thicker bands at the centre of the images were produced by light that enters the instrument through five slits at the centre.

Once in space, the micro-shutters will be opened or closed depending on the distribution of stars and galaxies in the sky.

This calibration image was obtained in 2017 during testing in the giant thermal vacuum chamber at NASA's Johnson Space Center in Houston, Texas. The tests demonstrated that the combined structure, comprising the Webb telescope and its four science instruments, operated flawlessly at temperatures of around -233°C, similar to those they will experience in space.

The telescope and instruments are now at Northrop Grumman Aerospace Systems in Redondo Beach, California, wh ere they will be integrated with the spacecraft and sunshield for further tests and launch preparations. The launch is targeted for 2020.
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https://news.northropgrumman.com/news/releases/nasas-james-webb-space-telescopes-two-halves-powered-for-the-first-time-in-one-building-at-northrop-grumman
ЦитатаNASA's James Webb Space Telescope's Two Halves Powered for the First Time in One Building at Northrop Grumman

June 20, 2018

REDONDO BEACH, Calif. - June 20, 2018 - Northrop Grumman Corporation (NYSE: NOC) has successfully powered up the two main parts of NASA's James Webb Space Telescope, a significant event in the test and integration phase of the program.
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NASA's James Webb Space Telescope OTIS (far right) and SCE (far left) featured in Northrop Grumman's Redondo Beach highbay.

The Webb Telescope's Optical Telescope element/Integrated Science instrument module (OTIS) and Spacecraft Element (SCE), which includes the sunshield and spacecraft bus, were separately powered at Northrop Grumman's facilities in Redondo Beach. This is the first time both halves were powered in the same building.

"This is a significant, first-time event for the program and for the team," said Scott Willoughby, vice president and program manager, James Webb Space Telescope, Northrop Grumman. "To power both OTIS and SCE moves us one step closer to readying the Webb for the next integration steps."


NASA's James Webb Space Telescope OTIS (far left) and SCE (mid picture) featured in Northrop Grumman's Redondo Beach highbay.

In the highbay, engineers use external power supplies, similar to chargers, which convert wall power to a source compatible with the spacecraft. This power is used to turn on the spacecraft and provides power to simulate what it will eventually use on orbit. Once in space, Webb will use solar arrays to operate the bus subsystems as well as the Science Instrument Payload.

The Spacecraft Element recently underwent a successful mechanical shock test in May. It was tested by simulating the mechanical shock caused by the separation of the spacecraft's payload adapter after launch. SCE will receive additional testing before being combined with the OTIS to form the complete James Webb Space Telescope observatory. Once the telescope is fully integrated, the entire observatory will undergo more tests during what is called observatory-level testing.

The James Webb Space Telescope will be the world's premier space science observatory of the next decade. 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 program led by NASA with its partners, the European Space Agency and the Canadian Space Agency.

Northrop Grumman is a leading global security company providing innovative systems, products and solutions in autonomous systems, cyber, C4ISR, strike, and logistics and modernization to customers worldwide. Please visit news.northropgrumman.com and follow us on Twitter, @NGCNews, for more information.

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https://www.nasa.gov/feature/goddard/2018/nasa-s-james-webb-space-telescope-to-target-jupiter-s-great-red-spot
ЦитатаJune 25, 2018

NASA's James Webb Space Telescope to Target Jupiter's Great Red Spot

NASA's James Webb Space Telescope, the most ambitious and complex space observatory ever built, will use its unparalleled infrared capabilities to study Jupiter's Great Red Spot, shedding new light on the enigmatic storm and building upon data returned from NASA's Hubble Space Telescope and other observatories.
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This photo of Jupiter, taken by NASA's Hubble Space Telescope, was snapped when the planet was comparatively close to Earth, at a distance of 415 million miles.
Credits: NASA, ESA, and A. Simon (NASA Goddard)


Jupiter's iconic storm is on the Webb telescope's list of targets chosen by guaranteed time observers, scientists who helped develop the incredibly complex telescope and among the first to use it to observe the universe. One of the telescope's science goals is to study planets, including the mysteries still held by the planets in our own solar system from Mars and beyond.

Leigh Fletcher, a senior research fellow in planetary science at the University of Leicester in the United Kingdom, is the lead scientist on the Webb telescope's observations of Jupiter's storm. His team is part of a larger effort to study several targets in our solar system with Webb, spearheaded by astronomer Heidi Hammel, the executive vice president of the Association of Universities for Research in Astronomy (AURA). NASA sel ected Hammel as an interdisciplinary scientist for Webb in 2002.

"Webb's infrared sensitivity provides a wonderful complement to Hubble visible-wavelength studies of the Great Red Spot," explained Hammel. "Hubble images have revealed striking changes in the size of the Great Red Spot over the mission's multi-decade-long lifetime."

Fletcher and his team plan to use Webb's mid-infrared instrument (MIRI) to create multispectral maps of the Great Red Spot and analyze its thermal, chemical and cloud structures. The scientists will be able to observe infrared wavelengths that could shed light on what causes the spot's iconic color, which is often attributed to the sun's ultraviolet radiation interacting with nitrogen, sulfur and phosphorus-bearing chemicals that are lifted from Jupiter's deeper atmosphere by powerful atmospheric currents within the storm.


This true-color image of Jupiter's Great Red Spot was created by citizen scientist Björn Jónsson using data from the JunoCam imager on NASA's Juno spacecraft.
Credits: NASA/JPL-Caltech/SwRI/MSSS/Björn Jónsson


Fletcher explained that using MIRI to observe in the 5 to 7 micrometer range could be particularly revealing for the Great Red Spot, as no other mission has been able to observe Jupiter in that part of the electromagnetic spectrum, and observations in such wavelengths are not possible from Earth. Those wavelengths of light could allow the scientists to see unique chemical byproducts of the storm, which would give insight into its composition.

"We'll be looking for signatures of any chemical compounds that are unique to the [Great Red Spot]...which could be responsible for the red chromophores," said Fletcher. Chromophores are the parts of molecules responsible for their color. Fletcher added, "If we don't see any unexpected chemistry or aerosol signatures...then the mystery of that red color may remain unresolved."

Webb's observations may also help determine whether the Great Red Spot is generating heat and releasing it into Jupiter's upper atmosphere, a phenomenon that could explain the high temperatures in that region. Recent NASA-funded research showed that colliding gravity waves and sound waves, produced by the storm, could generate the observed heat, and Fletcher said Webb might be able to gather data to support this.

"Any waves produced by the vigorous convective activity within the storm must pass through the stratosphere before they reach the ionosphere and thermosphere," he explained. "So if they really do exist and are responsible for heating Jupiter's upper layers, hopefully we'll see evidence for their passage in our data."

Generations of astronomers have studied the Great Red Spot; the storm has been monitored since 1830, but it has possibly existed for more than 350 years. The reason for the storm's longevity largely remains a mystery, and Fletcher explained that the key to understanding the formation of storms on Jupiter is to witness their full life cycle -- growing, shrinking, and eventually dying. We did not see the Great Red Spot form, and it may not die anytime soon (though it has been shrinking, as documented by images fr om NASA's Hubble Space Telescope and other observatories), so scientists must rely on observing "smaller and fresher" storms on the planet to see how they begin and evolve, something that Webb may do in the future, said Fletcher.

"These particular observations will reveal the storm's vertical structure, which will be an important constraint for numerical simulations of Jovian [Jupiter] meteorology," he explained. "If those simulations can help explain what Webb observes in the infrared, then we'll be a step closer to understanding how these gigantic maelstroms live for so long."

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 Eric Villard / Laura Betz
NASA's Goddard Space Flight Center
Last Updated: June 25, 2018
Editor: Lynn Jenner

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ЦитатаJames Webb Space Telescope: An Overview

NASA Goddard

Опубликовано: 26 июн. 2018 г.

The James Webb Space Telescope will be the largest telescope ever sent into space. It is the result of efforts from NASA, the European Space Agency and the Canadian Space Agency and will peer to the edges of the visible universe. This video highlights some of the Webb's most impressive facts.
https://www.youtube.com/watch?v=5l63I9JpWgAhttps://www.youtube.com/watch?v=5l63I9JpWgA (2:46)

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ЦитатаJeff Foust‏ @jeff_foust 32 мин. назад

NASA announced a briefing tomorrow at 1 pm EDT for an update on JWST, including findings of a recent independent review board. (And, presumably, new cost and schedule estimates.)
https://www.nasa.gov/press-release/nasa-hosts-media-teleconference-on-status-of-james-webb-space-telescope-0
ЦитатаAudio of the call will stream live on NASA's website.
17:00 UTC 2018-06-27

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ЦитатаJim Bridenstine‏Verified account @JimBridenstine 14m14 minutes ago

The James Webb Space Telescope will produce first of its kind, world-class science. Based on recommendations by an Independent Review Board, the new launch date for @NASAWebb is March 30, 2021. I'm looking forward to the launch of this historic mission.


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https://www.nasa.gov/press-release/nasa-completes-webb-telescope-review-commits-to-launch-in-early-2021
ЦитатаJune 27, 2018

NASA Completes Webb Telescope Review, Commits to Launch in Early 2021

The Independent Review Board (IRB) established by NASA to assess progress on its James Webb Space Telescope has unanimously recommended that development on the world's premier science observatory should continue; NASA has established a new launch date for Webb of March 30, 2021.

A report issued by the review board addresses a range of factors influencing Webb's schedule and performance, including the technical challenges and tasks remaining by primary contractor Northrop Grumman before launch.

Read the full report and NASA's response at:

 James Webb Space Telescope IRB Report and NASA Response
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"Webb should continue based on its extraordinary scientific potential and critical role in maintaining U.S. leadership in astronomy and astrophysics," said Tom Young, the chair of the review board. "Ensuring every element of Webb functions properly before it gets to space is critical to its success."

The board also reaffirmed Webb's significant complexity, incredible scientific potential, and importance to astrophysics. The report includes several recommendations for moving forward, some of which NASA has already initiated. The agency agrees with the review board's expert guidance on decisive steps necessary to safeguard and complete the telescope's development.

NASA Administrator Jim Bridenstine sent a message to the NASA workforce Wednesday about the report. "Webb is vital to the next generation of research beyond NASA's Hubble Space Telescope. It's going to do amazing things - things we've never been able to do before - as we peer into other galaxies and see light from the very dawn of time," said Administrator Bridenstine. "Despite major challenges, the board and NASA unanimously agree that Webb will achieve mission success with the implementation of the board's recommendations, many of which already are underway."

"The more we learn more about our universe, the more we realize that Webb is critical to answering questions we didn't even know how to ask when the spacecraft was first designed," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate. "Webb is poised to answer those questions, and is worth the wait. The valuable recommendations of the IRB support our efforts towards mission success; we expect spectacular scientific advances from NASA's highest science priority."

In its report, the IRB found that technical issues, including human errors, have greatly impacted the development schedule.

The agency previously had estimated an earlier launch date, but awaited findings from the IRB before making a final determination and considered data from Webb's Standing Review Board. The agency established the new launch date estimate to accommodate changes in the schedule due to environmental testing and work performance challenges by Northrop Grumman on the spacecraft's sunshield and propulsion system. The telescope's new total lifecycle cost, to support the revised launch date, is estimated at $9.66 billion; its new development cost estimate is $8.8 billion.

From detecting the light of the first stars and galaxies in the distant universe, to probing the atmospheres of exoplanets for possible signs of habitability, Webb's world-class science not only will shed light on the many mysteries of the universe, it also will complement and further enhance the discoveries of other astrophysics projects.

The first telescope of its kind, and an unprecedented feat of engineering, Webb is at the very leading edge of technological innovation and development. At its conception, challenges were anticipated for such a unique observatory of its size and magnitude. Webb was designed with highly sophisticated instruments to accomplish the ambitious scientific goals outlined in the National Academy of Sciences 2000 Decadal Survey - to answer the most fundamental questions about our cosmic origins.

Webb will be folded, origami-style, for launch inside Arianespace's Ariane 5 launch vehicle fairing - about 16 feet (5 meters) wide. After its launch, the observatory will complete an intricate and technically-challenging series of deployments - one of the most critical parts of Webb's journey to its final orbit, about one million miles from Earth. When completely unfurled, Webb's primary mirror will span more than 21 feet (6.5 meters) and its sunshield will be about the size of a tennis court.

Because of its size and complexity, the process of integrating and testing parts is more complicated than that of an average science mission. Once the spacecraft element has completed its battery of testing, it will be integrated with the telescope and science instrument element, which passed its tests last year. The fully-assembled observatory then will undergo a series of challenging environmental tests and a final deployment test before it is shipped to the launch site in Kourou, French Guiana.

Webb is an international project led by NASA with its partners, the ESA (European Space Agency) and the Canadian Space Agency.

-end-
Last Updated: June 27, 2018
Editor: Brian Dunbar
webb_irb_report_and_response_0.pdf - 5.1 MB, 69 стр, 2018-06-27 16:30:42 UTC

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ЦитатаChris G - NSF‏ @ChrisG_NSF 10 мин. назад

Five issues lead to delays to March 2021.

1. Human errors
2. Embedded problems
3. Lack of experience
4. Excessive optimism
5. Complexity
#JWST #JamesWebb #NASA

10 мин. назад

IRB is - again - very critical of Northrop Grumman, noting that simple checks to make sure right equipment/solvents were being use were not done. Those errors cost $600 million.
#JWST #JamesWebb #NASA

9 мин. назад

"The complexity and risk cannot be overestimated."
#JWST #JamesWebb #NASA

7 мин. назад

The new launch DOES NOT take into account any more avoidable, multi-month delay issues with integration.
#JWST #NASA @NASAWebb

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ЦитатаWilliam Harwood‏ @cbs_spacenews 20 мин. назад

JWST: Steve Jurczyk, NASA associate administrator, says an additional $837 million will be needed in out-year budget requests to cover higher development costs

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ЦитатаJeff Foust‏ @jeff_foust 22 мин. назад

Some questions in the call concerned Ariane 5 might not be around. Arianespace, as I recall, is planning a gradual phaseout of the rocket through the early 2020s, so it (shouldn't) be an issue.

Chris G - NSF‏ @ChrisG_NSF 20 мин. назад

#NASA clarifies: We've been told in no uncertain terms that Ariane 5 launcher will be around & available for March 2021 launch of #JWST. NASA has NOT had any further discussion beyond that date regarding upcoming retirement of Ariane 5 in favor of Ariane 6 (set to debut in 2020)