Best Telescope:Телескоп Гершель,OWL, JWST, greatest views

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Администрация Д. Трампа объявила о том, что она предлагает выделить космическому агентству США в 2019 году около $19.6 млрд. и ищет способы завершить финансирование МКС в 2025 году. Помимо этого, Белый дом также предлагает отменить миссию WFIRST. Ранее этот проект уже подвергался давлению со стороны администрации США, в частности по результатам перепланирования его стоимость была сокращена с $3.9 млрд. до $3.2 млрд. Несмотря на это, Белый дом посчитал, что после того как будет запущен телескоп James Webb Space Telescope (стоимость $8.8 млрд) , создание нового телескопа не является приоритетным. Документ не объясняет куда планируется перенаправить высвободившиеся средства.

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https://ria.ru/science/20180301/1515558815.html

МОСКВА, 1 мар – РИА Новости. Запуск телескопа "Джеймс Уэбб", самой дорогой обсерватории мира, может быть отложен на конец 2019 года или начало 2020 года из-за проблем в работе системы разворачивания его главного зеркала, открытых во время его тестирования на Земле, сообщает онлайн-издание SpaceNews.

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"Нам будет очень тяжело уложиться в текущую программу запуска миссии. Мы надеемся, что мы завершим все проверки и запустим телескоп в космос примерно через полтора года", — заявил Грег Робинсон (Greg Robinson), заместитель главы директората научных миссий в НАСА.
Новый телескоп "Джеймс Уэбб" (James Webb Space Telescope, JWST) является официальной заменой для орбитального телескопа "Хаббл", который проработал на орбите уже 25 лет.
Изначально новый аппарат планировалось запустить в 2014 году, но чрезмерно высокие затраты на его постройку и отставание от графика вынудили НАСА перенести предполагаемую дату старта миссии сначала на сентябрь 2015 года, потом – на октябрь 2018 года, и затем — на июль 2019 года. Конгресс США неоднократно пытался "закрыть" проект из-за задержек в его сборке и выход за рамки бюджета.
В начале декабря 2016 года инженеры НАСА заявили о возможном появлении больших проблем у "Джеймса Уэбба" – акселерометры, установленные на корпусе телескопа, зафиксировали некие неназванные аномалии во время вибрационных тестов. Это заставило НАСА провести детальную проверку телескопа, так как подобные аномалии могли указывать на наличие повреждений или трещин в инструментах или в корпусе "Джеймса Уэбба".
Как оказалось, проблемы действительно были, только они присутствовали не в конструкции самого телескопа, а в специальной системе креплений, которое удерживает "лепестки" зеркал "Джеймса Уэбба" на месте, не давая им развернуться.
Дело в том, что "Джеймс Уэбб", из-за своих огромных размеров будет отправлен в космос в сложенном виде. Его гигантское зеркало диаметром в 6,5 метра и экран аналогичных размеров, защищающий зеркало от Солнца, разделены на три части-"лепестка", которые отправятся в космос в сложенном виде, и раскроются только после вывода телескопа в космос.
Как передает SpaceNews, проблемы с ее креплениями, которые специалисты НАСА изучали и пытались ликвидировать весь прошлый год, "съели" фактически все резервное время, которое было изначально заложено в программе постройки телескопа на случай появления различных форс-мажорных обстоятельств.
По этой причине, как считают ревизоры НАСА, запуск обсерватории состоится не раньше лета 2019 года, если все остальные фазы ее проверки и подготовки к запуску пройдут идеально, без каких либо заминок или задержек. Это крайне маловероятно, из-за чего запуск "Джеймса Уэбба" может быть перенесен на вторую половину 2019 года или даже на начало 2020 года.
В свою очередь, это автоматически означает, что проект еще раз выйдет за рамки бюджета, что может опять привести к конфликту между НАСА, Конгрессом и Белым Домом, предпочитающим вкладывать новые средства в программу освоения Луны, а не в научные космические проекты.
Дополнительные сложности может создать и то, что ревизоры НАСА считают руководство миссии главными виновниками в появлении этих задержек, так как они проигнорировали рекомендации космического агентства по просчету всех рисков, которые были озвучены еще в 2012 году, после первого переноса сроков запуска "Джеймса Уэбба".

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GAO провело анализ выполнения проекта создания телескопа JWST.

GAO провело анализ выполнения проекта создания телескопа JWST. Согласно обнародованным материалам отчета:

1. В 2017 году космическое агентство США перенесло дату пуска на пять месяцев (c октября 2018 на период с марта по июнь 2019 года). Основной причиной переноса названы технические сложности с интеграцией и установкой оборудования. В основном это выразилось в том, что трудоемкость работ оказалась значительно выше чем планировалось. Прогнозные оценки стоимости проекта распределялись по годам как: 

-2007-2011 годы $1 - $3.5 млрд.;

-после 2011 года $8.835 млрд. 

2. К настоящему времени проект уже выбрал все имеющиеся у него резервы по времени и стоимости.

:?:

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NliteN‏ @NliteNinc 5 ч.5 часов назад


#JWST is not a @NASAHubble #Hubble successor,so STOP : JWST is a INFRARED telescope, Hubble is visible wavelength, Hubble is an extension of our eyes, JWST is Predatorvision.  @nasa needs to build & launch a true Hubble successor...on #FalconHeavy

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Wide Field Infrared Survey Telescope

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The WFIRST Project successfully completed its Systems Requirements Review (SRR) and Mission Definition Review (MDR) this week at NASA Goddard Space Flight Center. The Standing Review Board indicated that all requirements were successfully met and complimented the Project on its strong position proceeding into preliminary design. Over the next 6 weeks, the WFIRST Project will proceed through a series of Key Decision Point (KDP) gate reviews. WFIRST is the Decadal Survey's number 1 ranked astrophysics space mission, designed to explore the mystery of dark energy, study exoplanets to better understand our place in the Universe, and open-up an extraordinary discovery opportunity for general astrophysics.

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https://www.nasa.gov/feature/goddard/2018/nasa-s-webb-telescope-to-make-a-splash-in-search-for-interstellar-water

March 9, 2018

NASA's Webb Telescope to Make a Splash in Search for Interstellar Water

Water is crucial for life, but how do you make water? Cooking up some H2O takes more than mixing hydrogen and oxygen. It requires the special conditions found deep within frigid molecular clouds, where dust shields against destructive ultraviolet light and aids chemical reactions. NASA's James Webb Space Telescope will peer into these cosmic reservoirs to gain new insights into the origin and evolution of water and other key building blocks for habitable planets.

A molecular cloud is an interstellar cloud of dust, gas, and a variety of molecules ranging fr om molecular hydrogen (H2) to complex, carbon-containing organics. Molecular clouds hold most of the water in the universe, and serve as nurseries for newborn stars and their planets.

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In this animation we fly into a protoplanetary disk surrounding a young star. Within the disk, tiny dust grains accumulate layers of ice over thousands of years. These cosmic snowflakes are swept up by forming planets, delivering key ingredients for life.
Credits: NASA/JPL-Caltech/R. Hurt

Within these clouds, on the surfaces of tiny dust grains, hydrogen atoms link with oxygen to form water. Carbon joins with hydrogen to make methane. Nitrogen bonds with hydrogen to create ammonia. All of these molecules stick to the surface of dust specks, accumulating icy layers over millions of years. The result is a vast collection of "snowflakes" that are swept up by infant planets, delivering materials needed for life as we know it. "If we can understand the chemical complexity of these ices in the molecular cloud, and how they evolve during the formation of a star and its planets, then we can assess whether the building blocks of life should exist in every star system," said Melissa McClure of the Universiteit van Amsterdam, the principal investigator on a research project to investigate cosmic ices.

In order to understand these processes, one of Webb's Director's Discretionary Early Release Science projects will examine a nearby star-forming region to determine which ices are present wh ere. "We plan to use a variety of Webb's instrument modes and capabilities, not only to investigate this one region, but also to learn how best to study cosmic ices with Webb," said Klaus Pontoppidan of the Space Telescope Science Institute (STScI), an investigator on McClure's project. This project will take advantage of Webb's high-resolution spectrographs to get the most sensitive and precise observations at wavelengths that specifically measure ices. Webb's spectrographs, NIRSpec and MIRI, will provide up to five times better precision that any previous space telescope at near- and mid-infrared wavelengths.

Infant stars and comet cradles

The team, led by McClure and co-principal investigators Adwin Boogert (University of Hawaii) and Harold Linnartz (Universiteit Leiden), plans to target the Chamaeleon Complex, a star-forming region visible in the southern sky. It's located about 500 light-years from Earth and contains several hundred protostars, the oldest of which are about 1 million years old. "This region has a bit of everything we're looking for," said Pontoppidan.



This simulated spectrum from the Webb telescope illustrates the kinds of molecules that may be detected in star-forming regions like the Eagle Nebula (background).
Credits: NASA, ESA, the Hubble Heritage Team, and M. McClure (Universiteit van Amsterdam) and A. Boogert (University of Hawaii)

The team will use Webb's sensitive infrared detectors to observe stars behind the molecular cloud. As light from those faint, background stars passes through the cloud, ices in the cloud will absorb some of the light. By observing many background stars spread across the sky, astronomers can map ices within the cloud's entire expanse and locate wh ere different ices form. They will also target individual protostars within the cloud itself to learn how ultraviolet light from these nascent stars promotes the creation of more complex molecules.

Astronomers also will examine the birthplaces of planets, rotating disks of gas and dust known as protoplanetary disks that surround newly formed stars. They will be able to measure the amounts and relative abundances of ices as close as 5 billion miles from the infant star, which is about the orbital distance of Pluto in our solar system.

"Comets have been described as dusty snowballs. At least some of the water in Earth's oceans likely was delivered by the impacts of comets early in our solar system's history. We'll be looking at the places wh ere comets form around other stars," explained Pontoppidan.

Laboratory experiments

In order to understand Webb's observations, scientists will need to conduct experiments on Earth. Webb's spectrographs will spread incoming infrared light into a rainbow spectrum. Different molecules absorb light at certain wavelengths, or colors, resulting in dark spectral lines. Laboratories can measure a variety of substances to create a database of molecular "fingerprints." When astronomers see those fingerprints in a spectrum from Webb, they can then identify the molecule or family of molecules that created the absorption lines.

"Laboratory studies will help address two key questions. The first is what molecules are present. But just as important, we'll look at how the ices got there. How did they form? What we find with Webb will help inform our models and allow us to understand the mechanisms for ice formation at very low temperatures," explained Karin Öberg of the Harvard-Smithsonian Center for Astrophysics, an investigator on the project.

"It will take years to fully mine the data that comes out of Webb," Öberg added.

The James Webb Space Telescope will be the world's premier infrared space observatory of the next decade. Webb will help humanity solve the 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, ESA (European Space Agency) and CSA (Canadian Space Agency).

For more information about Webb, visit www.nasa.gov/webb or www.webbtelescope.org.

Caption for top image: Blue light from a newborn star lights up the reflection nebula IC 2631. This nebula is part of the Chamaeleon star-forming region, which Webb will study to learn more about the formation of water and other cosmic ices. Credits: European Southern Observatory (ESO)

By Christine Pulliam
Space Telescope Science Institute, Baltimore, Md.

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Last Updated: March 9, 2018
Editor: Lynn Jenner

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Миссия Кеплера, начатая в 2009 году, изменила наше понимание нашего места в галактике, дав нам надежду, что мы не одиноки. Почтенный космический корабль оказался искусным изобретать себя, когда что-то идет не так. Но инженеры по мониторингу Кеплера объявили, что миссия скоро подойдет к концу, поскольку на космическом корабле заканчивается топливо.
" Мы всегда знали, что срок службы Kepler будет ограничен количеством топлива в баке", - сказал Томас Баркли, бывший старший научный сотрудник с миссиями Kepler и K2. "Похоже, что это произойдет в какой-то момент в ближайшие несколько месяцев, хотя мы до сих пор точно не знаем, когда.
Барклай сказал, что сроки, когда топливный бак двигателя будет пустым, несколько трудно оценить.
Кеплер произвел революцию в том, что мы знаем о количестве экзопланет в нашей галактике. Космический телескоп обнаружил 2 245 экзопланет, еще 2 342 из которых ждут подтверждения.
Статистический анализ данных с космического корабля "планета-охота" показывает ошеломляющие цифры: наша Галактика имеет по крайней мере 100 миллиардов планет, и около 17 процентов звезд имеют планету земного размера. Это означает, что есть по крайней мере 17 миллиардов земных миров.

NASA's Kepler Space Telescope Is Nearing the End as Its Fuel Supply Runs Low

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Предыдущее упоминание (#369)

Liss 02.05.2013 пишет:
Говорят, в начале апреля GLAST был вынужден уворачиваться от "Космоса-1805" после прогноза сближения на 200 метров.

Сегодня
https://ria.ru/science/20180322/1517000336.html

НАСА: телескоп "Ферми" потерял контроль над солнечными батареями

© NASA
МОСКВА, 22 мар – РИА Новости. Орбитальная обсерватория "Ферми" временно вышла из строя и может потерять большую часть своей функциональности из-за заклинившего двигателя, управляющего положением одной из ее солнечных панелей, сообщает известный астроном Джонатан Макдауэлл.
"В 8 часов утра по Москве, 16 марта этого года, обсерватория "Ферми" зафиксировала неполадки в работе двигателя одного из блоков ее солнечных панелей. В результате этого зонд перешел в безопасный режим и отключил все инструменты. Сейчас специалисты НАСА пытаются раскрыть причину неполадки, и рассматривают возможность продолжать наблюдения, используя заклинившую панель", — цитирует ученый слова инженерной команды НАСА.
Гамма-телескоп "Ферми" был запущен на орбиту 11 июня 2008 года под именем GLAST и в августе был переименован в честь физика Энрико Ферми (1901-1954), одного из участников Манхэттенского проекта и основоположника физики высоких энергий.

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На аппарате установлены два главных инструмента — телескоп LAT, предназначенный для обзора неба в гамма-диапазоне, и детектор гамма-вспышек GBM.
За десять лет работы он успел открыть тысячи новых гамма-всплесков, гигантских черных дыр и прочих объектов, излучающих свет самых высоких энергий, в том числе и след от слияния двух пульсаров, открытый гравитационной обсерваторией LIGO в августе прошлого года.
Как отмечают инженеры НАСА, проблемы с двигателями солнечных батарей могут серьезно ограничить функционал или вообще поставить крест на дальнейшей научной карьере "Ферми". Этот телескоп вращается по достаточно низкой круговой орбите вокруг Земли, и в некоторых ее точках он будет получать крайне мало энергии от Солнца, если его батареи потеряют способность менять свое положение.
По словам команды "Ферми", пока не понятно, что именно перестало работать в двигателе панели – вполне возможно, что этот сбой имеет не механическую, а электронную природу, и в таком случае он не обязательно будет фатальным для космического аппарата. Сейчас инженеры НАСА пытаются найти ответ на этот вопрос и рассматривают варианты по уменьшению энергопотребления для возобновления научной части миссии.

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https://www.nasa.gov/press-release/nasa-hosts-media-teleconference-on-status-of-james-webb-space-telescope

March 27, 2018
MEDIA ADVISORY M18-054

NASA Hosts Media Teleconference on Status of James Webb Space Telescope

NASA will host a media teleconference at 11:30 a.m. EDT Tuesday, March 27, to provide an update on the agency's James Webb Space Telescope – what will be the world's premier infrared space observatory and the biggest astronomical science telescope ever built. Audio of the call will stream live on NASA's website.

The briefing participants are:

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• Acting NASA Administrator Robert Lightfoot
• Associate Administrator of NASA's Science Mission Directorate (SMD) Thomas Zurbuchen
• Deputy Associate Administrator of SMD Dennis Andrucyk
  

To participate in the call, media must send their name, affiliation and phone number to Felicia Chou at felicia.chou@nasa.gov no later than 11 a.m. March 27.

The most technically demanding and powerful space observatory ever developed, 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 will complement the scientific discoveries of NASA's Hubble Space Telescope and other science missions. Webb is an international project led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

Last Updated: March 27, 2018
Editor: Karen Northon

15:30 UTC

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https://www.nasa.gov/press-release/nasa-s-webb-observatory-requires-more-time-for-testing-and-evaluation-new-launch

March 27, 2018
RELEASE 18-019

NASA's Webb Observatory Requires More Time for Testing and Evaluation; New Launch Window Under Review

NASA's James Webb Space Telescope currently is undergoing final integration and test phases that will require more time to ensure a successful mission. After an independent assessment of remaining tasks for the highly complex space observatory, Webb's previously revised 2019 launch window now is targeted for approximately May 2020.

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"Webb is the highest priority project for the agency's Science Mission Directorate, and the largest international space science project in U.S. history. All the observatory's flight hardware is now complete, however, the issues brought to light with the spacecraft element are prompting us to take the necessary steps to refocus our efforts on the completion of this ambitious and complex observatory," said acting NASA Administrator Robert Lightfoot.

Testing the hardware on the observatory's telescope element and spacecraft element demonstrate that these systems individually meet their requirements. However, recent findings from the project's Standing Review Board (SRB) indicate more time is needed to test and integrate these components together and then perform environmental testing at Northrop Grumman Aerospace Systems in Redondo Beach, California, the project's observatory contractor.

NASA is establishing an external Independent Review Board (IRB), chaired by Thomas Young, a highly respected NASA and industry veteran who is often called on to chair advisory committees and analyze organizational and technical issues. The IRB findings, which will complement the SRB data, are expected to bolster confidence in NASA's approach to completing the final integration and test phase of the mission, the launch campaign, commissioning, as well as the entire deployment sequence. Both boards' findings and recommendations, as well as the project's input, will be considered by NASA as it defines a more specific launch time frame. NASA will then provide its assessment in a report to Congress this summer.

NASA will work with its partner, ESA (European Space Agency), on a new launch readiness date for the Ariane 5 vehicle that will launch Webb into space. Once a new launch readiness date is determined, NASA will provide a cost estimate that may exceed the projected $8 billion development cost to complete the final phase of testing and prepare for launch. Additional steps to address project challenges include increasing NASA engineering oversight, personnel changes, and new management reporting structures.

This is a pivotal year for Webb when the 6.5-meter telescope and science payload element will be joined with the spacecraft element to form the complete observatory. The spacecraft element consists of the tennis-court-sized sunshield, designed by Northrop Grumman, and the spacecraft bus, which houses the flight avionics, power system, and solar panels. Because of Webb's large size, engineers had to design components that fold origami-style into the Ariane 5 rocket's fairing configuration.

Webb has already completed an extensive range of tests to ensure it will safely reach its orbit at nearly one million miles from Earth and perform its science mission. As with all NASA projects, rigorous testing takes time, increasing the likelihood of mission success.

"Considering the investment NASA and our international partners have made, we want to proceed systematically through these last tests, with the additional time necessary, to be ready for a May 2020 launch," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate.

After the successful test performance of Webb's telescope and science payload in 2017 at NASA's Johnson Space Flight Center in Houston, the telescope element was delivered to Northrop Grumman earlier this year. Both halves of the 13,500-pound observatory now are together in the same facility for the first time.

The spacecraft element will next undergo environmental testing, subjecting it to the vibrational, acoustic and thermal environments it will experience during its launch and operations. These tests will take a few months to complete. Engineers then will integrate and test the fully assembled observatory and verify all components work together properly.

Webb is an international project led by NASA with its partners, ESA and the Canadian Space Agency. ESA is providing the Ariane 5 as part of its scientific collaboration with NASA.

The James Webb Space Telescope will be the world's premier infrared space observatory and the biggest astronomical space science telescope ever built, complementing the scientific discoveries of NASA's Hubble Space Telescope and other science missions. 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.

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Last Updated: March 27, 2018
Editor: Karen Northon

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Jeff Foust‏ @jeff_foust 6 мин. назад

Zurbuchen: May 2020 date is at the 70% confidence level; need to get to higher level before setting formal revised date.

Chris G - NSF‏ @ChrisG_NSF 6 мин. назад

Right now, there's only a 70% confidence level that May 2020 is achievable as a launch date for James Webb. #JWST #JamesWebb #NASA

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Chris G - NSF‏ @ChrisG_NSF 7 мин. назад

Sunshield tears and over-exertion, re-cabling, propulsion system testing errors... Man. This is really the worst case as outlined just last month by the Government Accountability Office. #JWST #JamesWebb #NASA

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Gene J. Mikulka‏ @genejm29 10 мин. назад

#NASA #JWST On Sunshield tears on snags in tension cables: Andrucyk: Had 7 tears in all f5 membranes tears were about 4 inches we want to understand how and why they happened, putting "doghouses" to constrain cable tensions.

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https://jwst.stsci.edu/news-events/news/News%20items/the-jwst-cycle-1-goar-proposal-deadline-has-been-delayed

The JWST Cycle 1 GO/AR Proposal Deadline Has Been Delayed
News Feature • March 27, 2018

Based on recommendations made by the JWST Standing Review Board, NASA is re-scheduling JWST's launch window for 2020. Given those circumstances, STScI will delay the Cycle 1 GO/AR proposal deadline until no earlier than February 1, 2019. A revised proposal schedule will be developed in consultation with the JWST Users Committee, the JWST Project, and representatives from the European and Canadian Space Agencies. Proposals already submitted in response to the Cycle 1 Call will not be carried over and will need to be resubmitted. Please submit any questions related to the Cycle 1 Call for Proposals to the JWST Help Desk

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Chris G - NSF‏ @ChrisG_NSF 8 мин. назад

#NASA delays #JamesWebb to NET May 2020. Cites need for more oversight of Northrop Grumman & integration issues. As article discusses, some issues were already known in last month's @USGAO report which said there was still 1.5 months schedule reserve.

https://www.nasaspaceflight.com/2018/03/nasa-delays-james-webb-launch-net-may-2020/ ...

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Jeff Foust‏ @jeff_foust 2 ч. назад

Slide from Zurbuchen's ongoing presentation at the National Academies on the status of JWST.

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Jeff Foust‏ @jeff_foust 1 ч. назад

Slide by Dennis Andrucyk on Webb delays, linked to propulsion system, sunshield and integration & test work:


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Andrucyk: standing review board came up with range of potential launch readiness dates from late January through late April 2020. The later date was a higher confidence level (70%), hence the "approximately May" 2020 estimate.

1 ч. назад

Andrucyk's slide summarizing the management changes being made at NASA and Northrop Grumman on JWST.

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Jeff Foust‏ @jeff_foust 1 ч. назад

Zurbuchen shows this slide comparing the complexity of JWST with WFIRST at same stage of development.

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http://tass.ru/kosmos/5072992

NASA 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.
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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.

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https://spaceflightnow.com/2018/03/27/webb-telescopes-launch-delayed-until-2020/

Webb telescope's launch delayed until 2020
March 27, 2018 | Stephen Clark


The James Webb Space Telescope's mirror and instrument section, known as the Optical Telescope element and Integrated Science (OTIS) module, is unpacked fr om its shipping container after arriving at Northrop Grumman's satellite factory in Redondo Beach, California, earlier this year. JWST's sunshield is visible at left. Credit: NASA/Chris Gunn

Blaming a slew of technical snags and "avoidable errors," NASA officials said Tuesday that the launch of the James Webb Space Telescope, already years behind schedule, will be delayed to 2020, potentially pushing the mission's development cost above an $8 billion cap mandated by Congress.

Problems encountered in recent months with the observatory's spacecraft bus, the section that will host the mission's expandable telescope after liftoff, prompted a review of the schedule engineers need to prepare it for liftoff.

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"The project has achieved numerous successful milestones, and in fact, 100 percent of the observatory's flight hardware is now complete," said Robert Lightfoot, NASA's acting administrator. "However, work performance challenges that were brought to light have prompted us to take some action.

"We need to successfully integrate both halves of the observatory into the final flight configuration and complete some vital testing after an independent assessment of the remaining tasks," Lightfoot said Tuesday in a conference call with reporters. "Frankly, the tasks are taking longer to complete than we expected, which will result in a new target launch window, which we now expect to be approximately May of 2020."

NASA announced last September that JWST would miss its target launch date in October 2018, but managers still expected the observatory to be ready for liftoff between March and June of 2019. Officials on Tuesday said that was no longer possible.

All components of the observatory are in a clean room at Northrop Grumman's satellite factory in Redondo Beach, California, wh ere technicians will connect JWST's spacecraft platform — still under construction — to the mission's telescope and science module, which arrived at the contractor's plant earlier this year following assembly at NASA's Goddard Space Flight Center in Maryland and a cryogenic vacuum test at the Johnson Space Center in Houston.

The telescope and instruments have passed their standalone tests, but the team in charge of building the spacecraft has run into problems, NASA officials said. A NASA review board determined earlier this month that the mission would likely not be ready to launch until 2020.

"More time is needed to test and integrate the highly complex sunshield and spacecraft section at Northrop Grumman," said Thomas Zurbuchen, associate administrator of NASA's science mission directorate. "That is taking longer to complete, and there are also a few mistakes that happened."

The flagship mission will be the most ambitious astronomical observatory ever launched, building on a quarter-century of discoveries made by NASA's famous Hubble Space Telescope. Originally proposed more than 20 years ago, the James Webb Space Telescope has been redesigned to expand its observing power and overcome numerous technical hurdles, ballooning costs fr om an original projection below $1 billion to more than $10 billion, a figure that includes planned launch and operations expenses, along with European and Canadian contributions.

The new observatory will be stationed nearly a million miles (1.5 million kilometers) from Earth, using a 21.3-foot (6.5-meter) mirror and four science instruments hidden behind a thermal sunshield to peer into the distant universe, studying the turbulent aftermath of the Big Bang, the formation of galaxies and the environments of planets around other stars.


The sunshield for James Webb Space Telescope is pictured in flight configuration after a deployment test last year. Credit: Northrop Grumman

Lightfoot said NASA has invested $7.3 billion to date in the James Webb Space Telescope, named for the NASA administrator who led the agency during the Space Race of the 1960s.

NASA remains committed to the observatory, but with the launch delay to 2020, the cost to develop the mission could rise above an $8 billion lim it set by lawmakers. If that happens, the mission must be reviewed and reauthorized by Congress.

"The James Webb Space Telescope is our highest priority science project within NASA's science mission directorate," Lightfoot said. "It's really a tremendous feat of human engineering, and it's going to leave a legacy of exceptional science and technical innovations for decades. It's loaded with pioneering technology, and it's also the largest international space science project in U.S. history."

NASA officials did not provide a new cost estimate to finish development of the observatory. Agency leaders will submit a report to Congress by late June to inform lawmakers of the mission's upd ated schedule and budget.

"The moment we have any indication that a breach will happen, both in schedule and cost, we need to inform right away," Zurbuchen said. "The disadvantage of that kind of sudden action is that we have not fully done all our entire joint analysis of cost and schedule, and we actually, at this moment in time, don't really fully know what the exact cost will be of the entire completed and deployment spacecraft."

If NASA needs relatively little extra money to complete JWST, future expenditures planned for the observatory's post-launch operations could be applied to finish assembly and testing of the spacecraft on Earth, Zurbuchen said. If the budget ends up well above NASA's previous expectation, the impacts to the agency's other science missions could be more severe, assuming Congress gives the green light to proceed with the observatory's final testing and launch.

Zurbuchen and his deputy in NASA's science mission directorate, Dennis Andrucyk, said a series of problems beset the observatory's spacecraft module over the last year.

"There have been a couple of technical challenges ... primarily in the propulsion system, we've had a schedule delay due to a transducer that was incorrectly powered," Andrucyk said. "We needed to replace that. That resulted in a three-month hit. Incorrect solvent was run through prop system. As a result, we wound having to replace valves in that system, and a catalyst bed heater was accidentally overstressed (at the wrong voltage) and needed to be replaced."

Andrucyk characterized the propulsion system issues as "avoidable errors."

"The sunshield complications also took a toll on the schedule," he said. "It's a very large five-layer membrane sysstem about the size of a tennis court, and during the deploy, fold and stow operations, the amount of time that we expected to perform those activities took longer than we expected. The first deploy we expected to be two weeks. It wound up being a month, and in the fold and stow, we expected it to be about a month, and it wound up being two months. We have two additional of those deploy, fold and stow operations to go."

Engineers discovered seven tears across five of the sunshield membranes, which will ensure the observatory's detectors and mirrors remain protected from heat and light from the sun, keeping parts of the spacecraft as cold as minus 370 degrees Fahrenheit, or minus 223 degrees Celsius. Internal coolers will chill some of the telescopes's sensors even colder.

"Also, the sunshield tensioning system, the cables that hold the sunshield membrane into its shape, developed too much slack during the deployment, creating a snagging hazard," Zurbuchen said. "So they had to redesign how the cables straddle certain parts of the boom so that wouldn't happen."

The sunshield tears have been repaired, officials said.


Artist's concept of the James Webb Space Telescope in its fully deployed configuration. Credit: NASA/Space Telescope Science Institute

Once the telescope and spacecraft sections are connected, ground crews at Northrop Grumman will again deploy the sunshield, along with the telescope's unfoldable wings and other structures, then put the entire observatory through electrical, vibration and acoustic tests. After those checks are complete, technicians will unfurl the full observatory once more before stowing it into launch configuration.

The testing is geared toward ensuring the mission's post-launch deployments go off without a hitch.

The sunshield and mirror will fold up origami-style to fit inside the envelope of the European Ariane 5 rocket that will launch JWST from French Guiana. The Ariane 5 launcher is one of the European Space Agency's major contributions to the mission, along with key instrument hardware.

Depending on how you count, JWST will have more than 300 deployments after it separates from from the upper stage of the Ariane 5 launcher. Counting steps in a similar way, the Curiosity Mars rover had around 70 deployments.

"Webb is really complex," Zurbuchen said. "Extensive and rigorous testing is necessary to ensure that we have a launch, deployment and checkout that succeeds with high confidence.

"Webb will journey to an orbit about a million miles from the Earth, four times farther than the moon," Zurbuchen said. "Simply put, we have one shot to get this right before going into space. You've heard this before, and it rings true for Webb, for us, really failure is not an option."

Andrucyk said NASA Headquarters will have more oversight over JWST in the future, including direct interaction with Northrop Grumman's president and chief operating officer. NASA will also dispatch a project manager to Northrop Grumman's factory in Southern California on a permanent basis, along with additional NASA spacecraft integration and test experts during critical operations.

NASA will also have daily and weekly schedule reviews with Northrop Grumman, which will also revamp its management structure. Northrop Grumman is also making personnel changes and updating procedures.

Andrucyk said Tuesday at a meeting at the National Academies of Sciences that some of the recent JWST problems "were driven by poorly written procedures."

"Northrop Grumman remains steadfast in its commitment to NASA and ensuring successful integration, launch and deployment of the James Webb Space Telescope, the world's most advanced space telescope," Northrop Grumman said in a statement.

An independent review board chaired by Thomas Young, a space industry veteran who served as an executive at Lockheed Martin and as mission director of NASA's Viking Mars landers, will help the space agency confirm a new target launch date and cost figure for JWST.

NASA's standing review board estimated the mission could be ready for launch by April 30, 2020, at a 70 percent confidence level, Andrucyk said at the National Academies of Sciences' Space Science Week meeting Tuesday. That led the agency's leaders to announce the mission was likely off until May 2020.

For the record, Andrucyk said, NASA's standing review board — comprised of engineers and managers not part of the JWST program — concluded the mission could launch in January 2020 with 30 percent confidence.

"Today's announcement that the James Webb Space Telescope launch will slip again and likely go over the $8 billion development cost cap is disappointing and unacceptable," said Rep. Lamar Smith (R-Texas), chairman of the House Science Committee.

Smith added in a statement that the delays and cost overruns "undermine confidence in NASA and its prime contractor, Northrop Grumman."

"NASA must keep their promises to the American taxpayers," Smith said. "Every time a mission is delayed or goes over budget, it negatively affects other science missions. This includes delays, cancellations and de-scoping of other missions. Those effects ripple out within NASA and through the entire scientific community.

"The James Webb Space Telescope is a crucial project and an investment in our future," Smith concluded in his statement. "I expect it to be completed within the cap and launched as close to on schedule as possible so we can look forward to the incredible discoveries it will bring."

The observatory survived a brush with cancellation by lawmakers in 2011, who proposed zeroing the mission's budget. An independent review in 2010 found that the mission needed more money to maintain a target launch date in 2015, and NASA and Congress eventually agreed to aim for JWST's launch in 2018, with additional funding to give managers a budget reserve to handle potential technical issues.

That funding reserve may prove insufficient, and officials admitted Tuesday that a 2018 launch was based on an optimistic schedule.

The Webb mission is se t to become the most expensive robotic science mission ever launched. The observatory's primary mirror — which collects light from astronomical sources — is nearly three times the diameter of Hubble's, and no other observatory of JWST's size is planned for launch until at least the 2030s.

Webb will enable "science that will look at the universe in a way we have never seen it," Zurbuchen said.

With another announcement that Webb's costs are rising, some worry that the mission's budget will hamstring NASA's ability to secure approval for future flagship-class science missions. Zurbuchen said missions like JWST have strong value, pushing frontiers in technology and scientific productivity that make future probes possible.

"One conclusion you could make is you shouldn't do complex missions like this," Zurbuchen said Tuesday afternoon at the National Academies of Sciences. "I will tell you that this would be a very grave and wrong assumption. At NASA, and together with our international partners, we should push the envelope.

"What we should do is not make stupid mistakes," he said. 'We should learn as we go, as fast as we can."

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