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

Автор ESA Vega, 02.10.2005 03:55:31

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Чебурашка

#460
WST уплыл на весну 2019 года

http://spaceref.com/news/viewpr.html?pid=51594
ЦитироватьNASA's James Webb Space Telescope to be Launched Spring 2019

Крутят гайки медленно
Цитироватьthe integration of the various spacecraft elements is taking longer than expected

tnt22

ЦитироватьЧебурашка пишет:
Круять гайки медленно
Официально от НАСА

https://www.nasa.gov/feature/nasa-s-james-webb-space-telescope-to-be-launched-spring-2019
Цитировать

Sept. 28, 2017

NASA's James Webb Space Telescope to be Launched Spring 2019

NASA's James Webb Space Telescope now is planning to launch between March and June 2019 from French Guiana, following a schedule assessment of the remaining integration and test activities. Previously Webb was targeted to launch in October 2018.
Спойлер
"The change in launch timing is not indicative of hardware or technical performance concerns," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate at Headquarters in Washington. "Rather, the integration of the various spacecraft elements is taking longer than expected."

As part of an international agreement with the ESA (European Space Agency) to provide a desired launch window one year prior to launch, NASA recently performed a routine schedule assessment to ensure launch preparedness and determined a launch schedule change was necessary. The careful analysis took into account the remaining tasks that needed to be completed, the lessons learned from unique environmental testing of the telescope and science instruments at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and the current performance rates of integrating the spacecraft element.

Testing of the telescope and science instruments continues to go well and on schedule at NASA's Johnson Space Center in Houston, Texas. The spacecraft itself, comprised of the spacecraft bus and sunshield, has experienced delays during its integration and testing at Northrop Grumman in Redondo Beach, California.

The additional environmental testing time of the fully assembled observatory--the telescope and the spacecraft--will ensure that Webb will be fully tested before launching into space. All the rigorous tests of the telescope and the spacecraft to date show the mission is meeting its required performance levels.

Existing program budget accommodates the change in launch date, and the change will not affect planned science observations.

"Webb's spacecraft and sunshield are larger and more complex than most spacecraft. The combination of some integration activities taking longer than initially planned, such as the installation of more than 100 sunshield membrane release devices, factoring in lessons learned from earlier testing, like longer time spans for vibration testing, has meant the integration and testing process is just taking longer," said Eric Smith, program director for the James Webb Space Telescope at NASA Headquarters in Washington. "Considering the investment NASA has made, and the good performance to date, we want to proceed very systemmatically through these tests to be ready for a Spring 2019 launch."

The launch window request has been coordinated with ESA, which is providing the Ariane 5 launch of Webb as part of its scientific collaboration with NASA.

The James Webb Space Telescope is NASA's next great multi-purpose observatory and will be the world's most powerful space telescope ever built, serving thousands of astronomers worldwide. The 21-foot (6.5-meter) diameter infrared-optimized telescope is designed to study an extremely wide range of astrophysical phenomena: the first stars and galaxies that formed; the atmospheres of nearby planets outside our solar system, known as exoplanets; and objects within our own solar system. Webb is an international project led by NASA with its partners ESA and the Canadian Space Agency.
[свернуть]
Last Updated: Sept. 28, 2017
Editor: Brian Dunbar
О потенциальном "конфликте интересов" с запуском BepiColombo уже писали

http://spacenews.com/spaceport-schedule-conflict-could-delay-jwst-launch/
ЦитироватьCurrent plans call for the launch of JWST on an Ariane 5 from the spaceport at Kourou, French Guiana, in October 2018. The European Space Agency is providing the launch of JWST as its contribution for the mission, in exchange for a share of observing time on the telescope.

However, ESA is also planning an October 2018 launch of BepiColombo, its first mission to Mercury, in cooperation with the Japanese space agency JAXA. That mission will also use an Ariane 5 launching from Kourou.
Спойлер
At a meeting of the NASA Advisory Council's science committee July 24, Alan Boss, an astronomer at the Carnegie Institution and a member of the Astrophysics Advisory Committee, warned that BepiColombo could take precedence over JWST for that October 2018 launch slot.

"BepiColombo has rights to launch before James Webb does," he said in a summary of a meeting of that advisory committee earlier in the month.

Boss didn't elaborate on the reasons for that precedence, but BepiColombo, unlike JWST, has a narrow launch window in order to reach Mercury. ESA officials said earlier in July that the mission's current launch window opens Oct. 5 and runs through Nov. 28. JWST does not have similar launch window restrictions.

While the Ariane 5 is capable of flying at a relatively high cadence — three Ariane 5 rockets launched in May and June of this year — the extensive payload processing requirements of both BepiColombo and JWST appear to rule out launching both missions around the same time.

"It's unclear if BepiColombo will be out of the way" before JWST arrives at Kourou for launch preparations, Boss said. He believed JWST needed three to six months of "full access" to facilities at Kourou to prepare for launch. "You really want to have BepiColombo long gone before you move in and start taking over."

If BepiColombo sticks to its current schedule, that could mean delaying JWST by several months. "There's some concern that that October 2018 launch may actually slip into the spring of 2019," he said.
[свернуть]
Т. е. всё было известно уже летом с.г., сейчас просто официально об этом объявили, поэтому и "гайки крутить" особо не поспешали, ПМСМ,  ;)

zandr

http://tass.ru/kosmos/4605590
ЦитироватьNASA: перенос на 2019 год вывода в космос нового телескопа вызван сложностью испытаний

© AP Photo/Alex Dominguez
ВАШИНГТОН, 30 сентября. /Корр. ТАСС Александр Пахомов/. Перенос на 2019 год вывода в космос нового телескопа James Webb вызван сложностью испытаний его конструкции и оборудования. Об этом корреспонденту ТАСС сообщили в пятницу в штаб-квартире Национального управления США по аэронавтике и исследованию космического пространства (NASA).
"James Webb и его солнцезащитный экран - более крупная и сложная конструкция, чем большинство других космических аппаратов, - пояснил причину отсрочки руководитель программы создания телескопа Эрик Смит. - Процесс сборки некоторых компонентов занял больше времени, чем планировалось. Это касается, к примеру, установки свыше 100 механизмов раскрытия солнцезащитного экрана. Кроме того, мы учитывали уроки, извлеченные при тестировании других компонентов обсерватории, в частности, больше времени потребовалось на вибрационные испытания модуля с аппаратурой на прочность".
"Мы хотим методично пройти через весь этот процесс, чтобы быть готовыми к запуску весной 2019 года", - добавил он.
Спойлер
Телескоп, названный в честь Джеймса Уэбба, руководителя программы "Аполлон", позволившей человеку побывать на Луне, должен заменить на орбите обсерваторию Hubble. Первоначально предполагалось, что это произойдет в 2013 году, однако реализация проекта, в который уже вложено около $8 млрд, сильно отстала 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. Ракету-носитель Ariane 5 пообещали предоставить европейцы, равно как и свой космодром Куру во Французской Гвиане.
[свернуть]
Но в минувший четверг NASA сообщило о решении отложить запуск на 2019 год - он должен состояться в период между мартом и июнем.
На обсерватории установлено зеркало диаметром 6,5 метра. Ее предполагается вывести далеко за Луну на орбиту, находящуюся на расстоянии примерно 1,6 млн км от поверхности Земли. В течение шести месяцев вся бортовая аппаратура будет проверена, и James Webb приступит к изучению древнейших во Вселенной звезд и галактик, сформировавшихся после Большого взрыва. Срок его эксплуатации рассчитан на 10 лет.


tnt22

ЦитироватьWhat Lurks Beneath NASA's Chamber A

NASA Goddard

Опубликовано: 18 окт. 2017 г.
Спойлер
Hidden below Chamber A at NASA's Johnson Space Center in Houston is an area engineers used to test critical contamination control technology that has helped keep NASA's James Webb Space Telescope clean during cryogenic testing.

This voluminous area is called the plenum, and it supports the weight of the chamber above as well as houses some of the cabling and plumbing for it. Before Webb's cryogenic testing in the chamber commenced, engineers ventured to the plenum's depths to test NASA-developed technology designed to remove molecular contaminants from the air.

Catching contaminants

Nithin Abraham, a coatings engineer at NASA's Goddard Space Flight Center in Greenbelt, Maryland, is part of a contamination control team tasked with ensuring Webb remains as clean as possible during its testing in Chamber A. Abraham developed and tested a highly permeable and porous material called molecular adsorber coating (MAC), which can be sprayed onto surfaces to passively capture contaminants that could be harmful to Webb's optics and science instruments.
[свернуть]
https://www.youtube.com/watch?v=2eOcMRhLvW8https://www.youtube.com/watch?v=2eOcMRhLvW8 (2:37)

tnt22

https://www.nasa.gov/feature/goddard/2017/what-lurks-below-nasas-chamber-a
ЦитироватьOct. 18, 2017

What Lurks Below NASA's Chamber A?

Hidden beneath Chamber A at NASA's Johnson Space Center in Houston is an area engineers used to test critical contamination control technology that has helped keep NASA's James Webb Space Telescope clean during cryogenic testing.
Спойлер
This voluminous area is called the plenum, and it supports the weight of the chamber above as well as houses some of the cabling and plumbing for it. Before Webb's cryogenic testing in the chamber commenced, engineers ventured to the plenum's depths to test NASA-developed technology designed to remove molecular contaminants fr om the air.


This large, empty area, called the plenum, sits just below Chamber A at NASA's Johnson Space Center in Houston. The white panels in the photograph are covered with a molecular adsorber coating (MAC) that was developed at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The coating helped keep NASA's James Webb Space Telescope free fr om contaminants during cryogenic testing in the chamber.
Credits: NASA/Chris Gunn


This diagram shows where the plenum is located in relation to Chamber A at NASA's Johnson Space Center in Houston. It also shows the walkway engineers use to access the hidden area.
Credits: NASA/Mike McClare, Adriana Manrique

Catching contaminants

Nithin Abraham, a coatings engineer at NASA's Goddard Space Flight Center in Greenbelt, Maryland, is part of a contamination control team tasked with ensuring Webb remains as clean as possible during its testing in Chamber A. Abraham is the principal investigator of the coatings research team that has developed and tested a highly porous material called molecular adsorber coating (MAC), which can be sprayed onto surfaces to passively capture contaminants that could be harmful to Webb's optics and science instruments.

Not to be confused with absorption, adsorption is the process in which microscopic materials (for example, atoms and molecules) adhere to a surface — in this case, to the surface of a panel coated with the MAC. The MAC panel secures contaminants released through outgassing, a process that occurs when gas that was dissolved, absorbed, or otherwise trapped within a substance is released into the surrounding environment. An example of this is the coveted "new car smell" of a freshly manufactured automobile.

Even minute amounts of outgassed material within the plenum could have posed a threat to Webb's optics and science instruments located in Chamber A, so Abraham and her team — engineers turned spelunkers — descended into the cave-like space to place the MAC panels before cryogenic testing began.


Coatings engineer Nithin Abraham places a molecular adsorber coating (MAC) panel in the plenum of Chamber A at NASA's Johnson Space Center in Houston.
Credits: NASA/Chris Gunn

To reach the plenum, the engineers walked single file along a narrow, mineshaft-like passageway between the helium shroud that surrounds the Webb telescope and the wall of the chamber, then descended a ladder into the cylindrical room. Light along the passageway and within the plenum is sparse, so the engineers donned headlamps before they made the journey. They also wore oxygen sensors to warn them if oxygen levels inside the plenum were getting low.

The MAC panels in the plenum primarily captured hydrocarbons and silicone-based compounds. These contaminants are ghosts of the Apollo era, when a mechanism within the central cylinder of the plenum rotated the floor of the chamber above. This rotation simulated the thermal roll used to evenly disperse heat on the Apollo spacecraft during their journeys to and from the Moon. Nithin and her team also placed MAC panels inside Chamber A, including on the outside of the helium shroud.

"We do a thorough analysis on the types of contaminants that were collected and how much," said Abraham. "That data is very useful and shows that we are protecting [the telescope] from molecular contamination."

Shielding the Webb telescope

MAC panels are only one type of contamination control protecting the Webb telescope from both microscopic and macroscopic threats. Engineers wear white cleanroom suits to prevent particles of skin, hair, and clothing fibers from depositing on the telescope. Similarly, Webb must move from cleanroom to cleanroom because the rooms are specially designed to reduce the amount of airborne particles present. Engineers enter the cleanrooms using airlocks, and the rooms have positive air pressure compared to their surrounding environment, so air flows out of the area and takes any potential contaminants with it.

Outgassing in space

When a spacecraft is exposed to the vacuum of space, outgassing occurs from epoxies, tapes, lubricants, plastics, and other materials used to construct it. For Webb, the biggest threat from outgassing comes early in its mission, shortly after launch when the telescope is cooling down but is still warm.

"Fortunately, warm things outgas but cold things not so much, so once the telescope and instruments go cold, the outgassing goes way down," explained Lee Feinberg, optical telescope element manager for the Webb telescope at Goddard.

Engineers will control the temperatures of the different parts of the observatory as it cools so outgassed molecules from one part do not deposit elsewh ere, such as on sensitive surfaces like the optics, but instead escape to space. Though the MAC is only being used terrestrially and peripherally for Webb, engineers are researching ways to apply the coating directly onto elements of future NASA spacecraft, as an added measure of protection.

After cryogenic testing at Johnson is complete, Webb's combined science instruments and optics journey to Northrop Grumman in Redondo Beach, California, wh ere they will be integrated with the spacecraft element, which is the combined sunshield and spacecraft bus. Together, the pieces form the complete James Webb Space Telescope observatory. Once fully integrated, the entire observatory will undergo more tests during what is called "observatory-level testing." This testing is the last exposure to a simulated launch environment before flight and deployment testing on the whole observatory.

https://www.youtube.com/watch?v=2eOcMRhLvW8
(youtube.com/watch?v=2eOcMRhLvW8, 2:37)
Hidden below Chamber A at NASA's Johnson Space Center in Houston is an area engineers used to test critical contamination control technology that has helped keep NASA's James Webb Space Telescope clean during cryogenic testing.
Credits: NASA's Goddard Space Flight Center/Mike McClare

Webb is expected to launch from Kourou, French Guiana, in the spring of 2019.

The James Webb Space Telescope, the scientific complement to NASA's Hubble Space Telescope, will be the premier space observatory of the next decade. Webb is an international project led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).

For more information about NASA's Webb telescope, visit: www.webb.nasa.gov or www.nasa.gov/webb

Read more about how we are keeping Chamber A free of contaminants:  https://www.nasa.gov/feature/goddard/nasa-technology-protects-webb-telescope-from-contamination

By Eric Villard and Rob Gutro
NASA's Goddard Space Flight Center
[свернуть]
Last Updated: Oct. 18, 2017
Editor: Lynn Jenner

tnt22

https://www.nasa.gov/feature/goddard/2017/self-portrait-of-nasa-s-james-webb-space-telescope-marks-critical-test
ЦитироватьOct. 19, 2017

Self-Portrait of NASA's James Webb Space Telescope Marks Critical Test

What appears to be a unique selfie opportunity was actually a critical photo for the cryogenic testing of NASA's James Webb Space Telescope in Chamber A at NASA's Johnson Space Center in Houston. The photo was used to verify the line of sight (the path light will travel) for the testing configuration.
Спойлер

Ball Aerospace optical engineer Larkin Carey is reflected in the James Webb Space Telescope's secondary mirror, as he photographs the line of sight for hardware used during an important test of the telescope's optics.
Credits: Ball Aerospace

During Webb's extensive cryogenic testing, engineers checked the alignment of all the telescope optics and demonstrated the individual primary mirror segments can be properly aligned to each other and to the rest of the system. This all occurred in test conditions that simulated the space environment where Webb will operate, and where it will collect data of never-before-observed portions of the universe. Verifying the optics as a system is a very important step that will ensure the telescope will work correctly in space.

The actual test of the optics involved a piece of support equipment called the ASPA, a nested acronym that means "AOS Source Plate Assembly." The ASPA is a piece of hardware that sits atop Webb's Aft Optics Subsystem (AOS), which is recognizable as a black "nose cone" that protrudes fr om the center of Webb's primary mirror. The AOS contains the telescope's tertiary and fine-steering mirrors. The ASPA is ground test hardware, and it will be removed fr om the telescope before it is launched into space.

https://www.youtube.com/watch?v=y9Z2GbFJWmo
(youtube.com/watch?v=y9Z2GbFJWmo, 0:20)
Light fr om objects in space is captured and reflected by the primary mirror of a telescope like Webb. The slightly curved (concave parabolic) primary mirror reflects a more focused beam of light out to the round secondary mirror. The secondary mirror is curved outward (convex hyperbolic), and it reflects an even more focused beam of light down through the center of the primary mirror. In the case of Webb, the Aft Optics Subsystem (AOS) is at the primary mirror's center. It contains the tertiary and fine-steering mirrors, which further focus and direct the light to the science instruments. The tertiary mirror also serves to minimize optical aberrations common in reflecting telescopes.
Credits: NASA, ESA, and G. Bacon (STScI)

During testing, the ASPA fed laser light of various infrared wavelengths into and out of the telescope, thus acting like a source of artificial stars. In the first part of the optical test, called the "half-pass" test, the ASPA fed laser light straight into the AOS, wh ere it was directed by the tertiary and fine-steering mirrors to Webb's science instruments, which sit in a compartment directly behind the giant primary mirror. This test let engineers make measurements of the optics inside the AOS, and how the optics interacted with the science instruments. Critically, the test verified the tertiary mirror, which is immovable, was correctly aligned to the instruments.


Ball Aerospace optical engineer Larkin Carey is shown connecting fiber optics to the AOS Source Plate Assembly (ASPA) above the James Webb Space Telescope's primary mirror, while tethered to a "diving board." All tools were also tethered, and all safety protocol for working over the mirror were closely followed.
Credits: NASA/Desiree Stover

In another part of the test, called the "pass-and-a-half" test, light traveled in a reverse path through the telescope optics. The light was again fed into the system from the ASPA, but upwards, to the secondary mirror. The secondary mirror then reflected the light down to the primary mirror, which sent it back up to the top of Chamber A. Mirrors at the top of the chamber sent the light back down again, wh ere it followed its normal path through the telescope to the instruments. This verified not only the alignment of the primary mirror itself but also the alignment of the whole telescope — the primary mirror, secondary mirror, and the tertiary and fine-steering mirrors inside the AOS.

Taken together, the half-pass and pass-and-a-half tests demonstrated all the telescope optics are properly aligned and that they can be aligned again after being deployed in space.

The photo, snapped by Ball Aerospace optical engineer Larkin Carey after the final fiber optic connections between ASPA and the laser source outside the chamber were made, verified the line of sight for the pass-and-a-half part of the test. The image was compared with one collected once the telescope was cold inside the chamber, to ensure any observed obscurations were due to the ASPA hardware and would not be present during science data collection on orbit.

In the photo, Carey is harnessed to a "diving board" over the primary mirror. All tools (including the camera) were tethered, and all safety protocol for working over the mirror were closely followed. Carey faced upwards and took the photo of the secondary mirror to verify the ASPA line of sight. The secondary mirror is reflecting him as well as the AOS, the ASPA, and the primary mirror below.


Close-up of Ball Aerospace optical engineer Larkin Carey connecting fiber optics to the AOS Source Plate Assembly (ASPA) above the James Webb Space Telescope's primary mirror, while tethered to a "diving board." All tools were also tethered, and all safety protocol for working over the mirror were closely followed.
Credits: NASA/Desiree Stover

"Intricate equipment is required to test an instrument as complex as the Webb telescope. The ASPA allowed us to directly test key alignments to ensure the telescope is working as we expect, but its location meant we had to have a person install over 100 fiber optic cables by hand over the primary mirror," said Allison Barto, Webb telescope program manager at Ball Aerospace. "This challenging task, which Larkin rehearsed many times to ensure it could be performed safely, also offered the opportunity to check the alignments by taking this 'selfie' prior to entering the test."

After cryogenic testing at Johnson is complete, Webb's combined science instruments and optics journey to Northrop Grumman in Redondo Beach, California, wh ere they will be integrated with the spacecraft element, which is the combined sunshield and spacecraft bus. Together, the pieces form the complete James Webb Space Telescope observatory. Once fully integrated, the entire observatory will undergo more tests during what is called "observatory-level testing." This testing is the last exposure to a simulated launch environment before flight and deployment testing on the whole observatory.

Webb is expected to launch from Kourou, French Guiana, in the spring of 2019.

The James Webb Space Telescope, the scientific complement to NASA's Hubble Space Telescope, will be the premier space observatory of the next decade. Webb is an international project led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).

For more information about the Webb telescope visit: www.webb.nasa.gov or www.nasa.gov/webb

By Maggie Masetti
NASA's Goddard Space Flight Center
[свернуть]
Last Updated: Oct. 19, 2017
Editor: Lynn Jenner

tnt22

https://news.northropgrumman.com/news/releases/sunshield-deployment-and-layers-fully-tensioned-on-nasas-james-webb-space-telescope
ЦитироватьSunshield Deployment and Layers Fully Tensioned on NASA's James Webb Space Telescope

October 26, 2017

REDONDO BEACH, Calif. – Oct. 26, 2017 – Northrop Grumman Corporation (NYSE: NOC), which designed NASA's James Webb Space Telescope's (JWST) optics, spacecraft bus, and sunshield for NASA Goddard Space Flight Center, has deployed the sunshield subsystem and fully tensioned the five sunshield layers for the first time.
Спойлер

At Northrop Grumman highbay facilities in Redondo Beach, California, NASA's James Webb Space Telescope's five sunshield layers are fully tensioned for the first time.

"The first tensioning of the sunshield is a monumental and exciting moment, not only for the program but for the collaborative JWST team," said Scott Willoughby, vice president and program manager, James Webb Space Telescope, Northrop Grumman Aerospace Systems "The innovative sunshield is an industry first, and will protect Webb's optics from heat, making it possible to gather images of the formation of the first stars and galaxies more than 13.5 billion years ago."

In space, the sunshield subsystem divides the JWST observatory into a warm sun-facing side and a cold space-facing side comprised of the optics and scientific instruments. The sunshield subsystem, which includes the structure and mechanisms required for deploying the five-layer subsystem, was designed, manufactured and assembled by Northrop Grumman, with the five membrane layers manufactured by the NeXolve Corporation in Huntsville, Alabama.

The flight membranes will be folded, stowed and tensioned again two additional times for testing. The folding and stowing method is how the membranes will be folded and stowed for launch. The sunshield layers, known for being the size of a tennis court, will protect and prevent the background heat from the Sun, Earth and Moon from interfering with JWST's infrared sensors.

The sunshield layers, each as thin as a human hair, work together to reduce the temperatures between the hot and cold sides of the observatory by approximately 570 degrees Fahrenheit. Moving from the sun-facing layer to the one closest to the telescope, each successive layer of the sunshield, which is made of Kapton, is cooler than the one below. The sunshield, along with the rest of the spacecraft, will fold origami-style into an Ariane 5 rocket.

The James Webb Space Telescope, the scientific complement to NASA's Hubble Space Telescope, will be the premier space observatory of the next decade. Webb is an international project 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.
[свернуть]

tnt22

ЦитироватьJames Webb Space Telescope Laser-Focused Sight

NASA Goddard

Опубликовано: 26 окт. 2017 г.

About 1 million miles away from the nearest eye surgeon, NASA's James Webb Space Telescope will be able to perfect its own vision while in orbit.
Спойлер
Though the Webb telescope will focus on stars and galaxies approximately 13.5 billion light-years away, its sight goes through a similar process as you would if you underwent laser vision correction surgery to be able to focus on an object 10 feet across the room. In orbit at Earth's second Lagrange point (L2), far from the help of a terrestrial doctor, Webb will use its near-infrared camera (NIRCam) instrument to help align its primary mirror segments about 40 days after launch, once they have unfolded from their unaligned stowed position and cooled to their operating temperatures.

Laser vision correction surgery reshapes the cornea of the eye to remove imperfections that cause vision problems like nearsightedness. The cornea is the surface of the eye; it helps focus rays of light on the retina at the back of the eye, and though it appears to be uniform and smooth, it can be misshapen and pockmarked with dents, dimples, and other imperfections that can affect a person's sight. The relative positioning of Webb's primary mirror segments after launch will be the equivalent of these corneal imperfections, and engineers on Earth will need to make corrections to the mirrors' positions to bring them into alignment, ensuring they will produce sharp, focused images.
[свернуть]
https://www.youtube.com/watch?v=tbVzOtCfh9Uhttps://www.youtube.com/watch?v=tbVzOtCfh9U (1:12)

tnt22

https://www.nasa.gov/feature/goddard/2017/nasa-s-james-webb-space-telescope-completes-final-cryogenic-testing
ЦитироватьNov. 20, 2017

NASA's James Webb Space Telescope Completes Final Cryogenic Testing

The vault-like, 40-foot diameter, 40-ton door of Chamber A at NASA's Johnson Space Center in Houston was unsealed on November 18, signaling the end of cryogenic testing for NASA's James Webb Space Telescope.
Спойлер

NASA's James Webb Space Telescope sits inside Chamber A at NASA's Johnson Space Center in Houston after having completed its cryogenic testing on Nov. 18, 2017. This marked the telescope's final cryogenic testing, and it ensured the observatory is ready for the frigid, airless environment of space.
Credits: NASA/Chris Gunn

The historic chamber's massive door opening brings to a close about 100 days of testing for Webb, a significant milestone in the telescope's journey to the launch pad. The cryogenic vacuum test began when the chamber was sealed shut on July 10, 2017. Scientists and engineers at Johnson put Webb's optical telescope and integrated science instrument module (OTIS) through a series of tests designed to ensure the telescope functioned as expected in an extremely cold, airless environment akin to that of space.

"After 15 years of planning, chamber refurbishment, hundreds of hours of risk-reduction testing, the dedication of more than 100 individuals through more than 90 days of testing, and surviving Hurricane Harvey, the OTIS cryogenic test has been an outstanding success," said Bill Ochs, project manager for the James Webb Space Telescope at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The completion of the test is one of the most significant steps in the march to launching Webb."

These tests included an important alignment check of Webb's 18 primary mirror segments, to make sure all of the gold-plated, hexagonal segments acted like a single, monolithic mirror. This was the first time the telescope's optics and its instruments were tested together, though the instruments had previously undergone cryogenic testing in a smaller chamber at Goddard. Engineers fr om Harris Space and Intelligence Systems, headquartered in Melbourne, Florida, worked alongside NASA personnel for the test at Johnson.

"The Harris team integrated Webb's 18 mirror segments at Goddard and designed, built, and helped operate the advanced ground support and optical test equipment at Johnson," said Rob Mitrevski, vice president and general manager of intelligence, surveillance, and reconnaissance at Harris. "They were a key, enabling part of the successful Webb telescope testing team."

The Webb telescope team persisted with the testing even when Hurricane Harvey slammed into the coast of Texas on Aug. 25 as a category 4 hurricane before stalling over eastern Texas and weakening to a tropical storm, where it dropped as much as 50 inches of rain in and around Houston. Many Webb telescope team members at Johnson endured the historic storm, working tirelessly through overnight shifts to make sure Webb's cryogenic testing was not interrupted. In the wake of the storm, some Webb team members, including team members from Harris, volunteered their time to help clean up and repair homes around the city, and distribute food and water to those in need.

"The individuals and organizations that have led us to this most significant milestone represent the very best of the best. Their knowledge, dedication, and execution to successfully complete the testing as planned, even while enduring Hurricane Harvey, cannot be overstated," said Mark Voyton, James Webb Space Telescope optical telescope element and integrated science instrument manager at Goddard. "Every team member delivered critical knowledge and insight into the strategic and tactical planning and execution required to complete all of the test objectives, and I am honored to have experienced this phase of our testing with every one of them."

Before cooling the chamber, engineers removed the air from it, which took about a week. On July 20, engineers began to bring the chamber, the telescope, and the telescope's science instruments down to cryogenic temperatures — a process that took about 30 days. During cool down, Webb and its instruments transferred their heat to surrounding liquid nitrogen and cold gaseous helium shrouds in Chamber A. Webb remained at "cryo-stable" temperatures for about another 30 days, and on Sept. 27, the engineers began to warm the chamber back to ambient conditions (near room temperature), before pumping the air back into it and unsealing the door.

"With an integrated team from all corners of the country, we were able to create deep space in our chamber and confirm that Webb can perform flawlessly as it observes the coldest corners of the universe," said Jonathan Homan, project manager for Webb's cryogenic testing at Johnson. "I expect [Webb] to be successful, as it journeys to Lagrange point 2 [after launch] and explores the origins of solar systems, galaxies, and has the chance to change our understanding of our universe."

While Webb was inside the chamber, insulated from both outside visible and infrared light, engineers monitored it using thermal sensors and specialized camera systems. The thermal sensors kept tabs on the temperature of the telescope, while the camera systems tracked the physical position of Webb to see how its components very minutely moved during the cooldown process. Monitoring the telescope throughout the testing required the coordinated effort of every Webb team member at Johnson.

"This test team spanned nearly every engineering discipline we have on Webb," said Lee Feinberg, optical telescope element manager for the Webb telescope at Goddard. "In every area there was incredible attention to detail and great teamwork, to make sure we understand everything that happened during the test and to make sure we can confidently say Webb will work as planned in space."

In space, the telescope must be kept extremely cold, in order to be able to detect the infrared light from very faint, distant objects. Webb and its instruments have an operating temperature of about 40 Kelvin (or about minus 387 Fahrenheit / minus 233 Celsius). Because the Webb telescope's mid-infrared instrument (MIRI) must be kept colder than the other research instruments, it relies on a cryocooler to lower its temperature to less than 7 Kelvin (minus 447 degrees Fahrenheit / minus 266 degrees Celsius).

To protect the telescope from external sources of light and heat (like the Sun, Earth and Moon), as well as from heat emitted by the observatory, a five-layer, tennis court-sized sunshield acts like a parasol that provides shade. The sunshield separates the observatory into a warm, sun-facing side (reaching temperatures close to 185 degrees Fahrenheit / 85 degrees Celsius) and a cold side (minus 400 degrees Fahrenheit / minus 240 degrees Celsius). The sunshield blocks sunlight from interfering with the sensitive telescope instruments.

Webb's combined science instruments and optics next journey to Northrop Grumman Aerospace Systems in Redondo Beach, California, wh ere they will be integrated with the spacecraft element, which is the combined sunshield and spacecraft bus. Together, the pieces form the complete James Webb Space Telescope observatory. Once fully integrated, the entire observatory will undergo more tests during what is called "observatory-level testing." This testing is the last exposure to a simulated launch environment before flight and deployment testing on the whole observatory.

Webb is expected to launch from Kourou, French Guiana, in the spring of 2019.

The James Webb Space Telescope, the scientific complement to NASA's Hubble Space Telescope, will be the premier space observatory of the next decade. Webb is an international project led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).

For more information about the Webb telescope visit: www.webb.nasa.gov or www.nasa.gov/webb

By Eric Villard
NASA's Goddard Space Flight Center
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Last Updated: Nov. 20, 2017
Editor: Lynn Jenner

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https://www.nasa.gov/feature/goddard/2017/nasas-james-webb-space-telescope-early-science-observations-revealed
ЦитироватьNov. 13, 2017

NASA's James Webb Space Telescope Early Science Observations Revealed

Astronomers around the world will have immediate access to early data fr om specific science observations from NASA's James Webb Space Telescope, which will be completed within the first five months of Webb's science operations. These observing programs were chosen from a Space Telescope Science Institute call for early release science proposals, and include examining Jupiter and its moons, searching for organic molecules forming around infant stars, weighing supermassive black holes lurking in galactic cores, and hunting for baby galaxies born in the early universe.
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"I'm thrilled to see the list of astronomers' most fascinating targets for the Webb telescope, and extremely eager to see the results. We fully expect to be surprised by what we find," said Dr. John C. Mather, Senior Project Scientist for the Webb telescope and Senior Astrophysicist at NASA's Goddard Space Flight Center, Greenbelt, Maryland.

The resulting observations will comprise the Director's Discretionary Early Release Science (DD-ERS), and cover the gamut of Webb science targets, from planets in our solar system to the most distant galaxies. The program provides the entire scientific community with immediate access to Webb data so they have the opportunity to analyze the data and plan follow-up observations.

"We were impressed by the high quality of the proposals received," said Dr. Ken Sembach, Director of the Space Telescope Science Institute (STScI) in Baltimore, Maryland. "These observing programs not only will generate great science, but also will be a unique resource for demonstrating the investigative capabilities of this extraordinary observatory to the worldwide scientific community."

The observations will also exercise all four of Webb's science instruments, so that the astronomical community can explore Webb's full potential. Webb has a minimum scientific lifetime of five years, so the scientific community will have to rapidly learn to use its advanced capabilities.


This artist's illustration represents the scientific capabilities of NASA's James Webb Space Telescope. Both imaging and spectroscopy will be central to the Webb mission.
Credits: NASA, ESA, and A. Feild (STScI)

"We want the research community to be as scientifically productive as possible, as early as possible, which is why I am so pleased to be able to dedicate nearly 500 hours of director's discretionary time to these ERS observations," said Sembach.

One of the most widely anticipated areas of research by Webb is to study planets orbiting other stars. When such an exoplanet passes in front of its host star, starlight filters through the planet's atmosphere, which absorbs certain colors of light depending on the chemical composition. Webb will measure this absorption, using its powerful infrared spectrographs, to look for the chemical fingerprints of the atmosphere's gasses. Astronomers initially will train their gaze onto gaseous Jupiter-sized worlds like WASP-39b and WASP-43b because they are easier targets on which to apply this technique. The results will help guide observing strategies for smaller, mostly rocky and more Earth-like super-Earths, wh ere atmospheric composition may give hints of a planet's potential habitability.

Webb also will peer into the distant universe, examining galaxies whose light has been stretched into infrared wavelengths by the expansion of space. This infrared region is beyond what Hubble can detect. Galaxy clusters are particularly rich sources of targets, since a cluster's gravity can magnify light from more distant background galaxies. DD-ERS observations will target regions of the sky already examined by Hubble's Frontier Fields program, such as the galaxy cluster MACS J0717.5+3745. Webb data will complement Hubble's, giving astronomers new insights into these cornucopias of galaxies.

Since Webb must remain shielded from sunlight, its field of view is limited to specific areas of the sky at certain times of year. As a result, the potential targets listed above may shift depending on the launch date.

More than 100 proposals for DD-ERS observations were submitted in August 2017. Of those, 13 programs requesting 460 hours of telescope time were selected following review by panels of subject matter experts and the STScI director.

Additional information about the selected DD-ERS proposals is available online.

The James Webb Space Telescope, the scientific complement to NASA's Hubble Space Telescope, will be the premier space observatory of the next decade. Webb is an international project led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).

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

Christine Pulliam / Ray Villard
 Space Telescope Science Institute, Baltimore, Md.
 410-338-4366 / 410-338-4514
cpulliam@stsci.edu / villard@stsci.edu
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Last Updated: Nov. 13, 2017
Editor: Lynn Jenner

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http://tass.ru/kosmos/4758501
ЦитироватьОрбитальный телескоп James Webb прошел испытания при минус 233 градусах

© NASA/Desiree Stover
НЬЮ-ЙОРК, 25 ноября. /Корр. ТАСС Игорь Борисенко/. Испытания в криогенной камере гигантского орбитального телескопа James Webb завершились в Космическом центре имени Джонсона в Хьюстоне (штат Техас). Как сообщил в пятницу интернет-портал Space.com, охлаждение в камере до минус 233 градусов Цельсия обеспечивали два контура: внешний был заполнен жидким азотом, а внутренний - жидким гелием. Даже ураган "Харви", обрушившийся в августе нынешнего года на Техас, не прервал испытаний.
Орбитальный телескоп находился в криогенной камере 90 суток, в это время проверялась не только устойчивость аппаратуры к сверхнизким температурам, но и возможности коррекции главного зеркала диаметром 6,5 м, составленного из 18 отдельных сегментов. "После 15 лет планирования испытаний, переоборудования криогенной камеры, сотни часов испытаний, призванных сократить возможность поломки аппаратуры, в результате усилий более 100 специалистов, работавших на протяжении 90 суток, испытания в криогенной камере успешно завершены", - отметил руководитель проекта создания орбитального телескопа Билл Охс.
Теперь телескоп будет доставлен на испытательный стенд корпорации Northrop Grumman в Редондо-Бич (штат Калифорния), где к нему будет пристыкован двигательный отсек. После этого всю конструкцию подвергнут новой серии тестов на вибрацию и перегрузки.
Вывод обсерватории на орбиту будет осуществлен в 2019 году ракетой-носителем Ariane 5 с космодрома Куру во Французской Гвиане, а затем телескоп после коррекции орбиты выйдет в точку Лагранжа L2 системы Солнце-Земля более чем в 1 млн километров от Земли.
В течение шести месяцев вся бортовая аппаратура будет проверена, затем James Webb сможет начать регулярные наблюдения древнейших во Вселенной звезд и галактик, сформировавшихся вскоре после Большого взрыва. Срок его эксплуатации рассчитан на 10 лет.


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https://www.nasa.gov/feature/goddard/2017/nasa-s-webb-telescope-emerges-from-chamber-a
ЦитироватьDec. 1, 2017

NASA's Webb Telescope Emerges fr om Chamber A

NASA's James Webb Space Telescope, or Webb, emerged from Chamber A at NASA's Johnson Space Center in Houston on Dec. 1 to prepare for its upcoming move to California.
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NASA's James Webb Space Telescope emerged from Chamber A at NASA's Johnson Space Center in Houston on Dec. 1, 2017, to prepare for its upcoming move to California.
Credits: NASA/Chris Gunn

The telescope's combined science instruments and optical element recently completed about 100 days of cryogenic testing inside Johnson's Chamber A, a massive thermal vacuum testing chamber at the center. Scientists and engineers at Johnson put Webb through a series of tests designed to ensure the telescope functioned as expected in an extremely cold, airless environment akin to that of space.


Engineers pose by NASA's James Webb Space Telescope shortly after it emerged from Chamber A at NASA's Johnson Space Center in Houston on Dec. 1, 2017.
Credits: NASA/Chris Gunn

This move outside the chamber brings Webb one step closer to its journey to Northrop Grumman Aerospace Systems in Redondo Beach, California, wh ere it will be integrated with its spacecraft element to form the complete James Webb Space Telescope observatory. The spacecraft element is Webb's combined sunshield and spacecraft bus.

The James Webb Space Telescope is the world's premier infrared space observatory of the next decade. A barrier-breaking mission for engineers and astronomers, 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 (ESA), and the Canadian Space Agency (CSA).

Take a look at the Webbcam to see Webb's current location in the Chamber A cleanroom!

For more information about the Webb telescope visit: www.webb.nasa.gov or www.nasa.gov/webb
 
By Eric Villard
NASA's Goddard Space Flight Center
[свернуть]
Last Updated: Dec. 1, 2017
Editor: Lynn Jenner

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https://spaceflightnow.com/2017/12/04/jupiters-moons-black-holes-and-exoplanets-among-jwsts-first-scientific-targets/
ЦитироватьJupiter's moons, black holes, exoplanets among JWST's first scientific targets
December 4, 2017 Stephen Clark

The James Webb Space Telescope should start returning its first scientific results by the end of 2019, and scientists recently announced a slate of observations sel ected to whet the appetites of astronomers who will use the multibillion-dollar facility well into the 2020s.
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Artist's concept of the James Webb Space Telescope. Credit: NASA/Northrop Grumman

The observatory's initial scientific targets will include Jupiter and its moons, supermassive black holes at the centers of galaxies, planets orbiting other stars, and some of the oldest observable galaxies in the universe.

The director of the Space Telescope Science Institute, Ken Sembach, sel ected 13 observation plans last month fr om more than 100 proposals submitted by global science teams for the chance to be among the first to use JWST after its launch in early 2019.

Officials expect to declare JWST operational around six months after its launch, allowing time for the spacecraft to cruise to its observing post at the L2 Lagrange point nearly a million miles (1.5 million kilometers) from Earth, deploy its segmented telescope, and complete a series of test imaging campaigns to fine-tune the observatory's performance.

Then JWST will be turned over to scientists, and two sets of observers will be the first to point the telescope toward celestial targets for scientific purposes. Research teams in the United States, Europe and Canada that helped develop JWST's four science instruments have guaranteed access once the telescope is operational, but managers opened up nearly 500 hours of observing time for other astronomers.

The 13 teams sel ected for the JWST Director's Discretionary Early Release Science Program will have access to the observatory for 460 hours of data-gathering. The 253 astronomers involved in the early observations come from 18 countries — the United States, European Space Agency member states, Canada, Australia and Chile.

"I'm thrilled to see the list of astronomers' most fascinating targets for the Webb telescope, and extremely eager to see the results. We fully expect to be surprised by what we find," said John Mather, JWST's senior project scientists and senior astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

While the instrument teams with guaranteed time on JWST will get to hold onto their results to conduct their own analyses, a key tenet the early science program is the immediate release of imagery and spectral data, giving a broader community of astronomers a chance to incorporate Webb's findings within a year of its launch.

"We were impressed by the high quality of the proposals received," said Ken Sembach, director of the Space Telescope Science Institute in Baltimore, Maryland. "These observing programs not only will generate great science, but also will be a unique resource for demonstrating the investigative capabilities of this extraordinary observatory to the worldwide scientific community."


Engineers inspect JWST's Mid-Infrared Instrument after its arrival at the Goddard Space Flight Center in Maryland from the United Kingdom in 2012. Credit: NASA/Chris Gunn

All four of JWST's science instruments will be employed in the early science program, which will extend fr om November 2019 through April 2020, assuming the mission remains on track for launch in early 2019.

"We want the research community to be as scientifically productive as possible, as early as possible, which is why I am so pleased to be able to dedicate nearly 500 hours of director's discretionary time to these ERS observations," Sembach said in a statement.

One of the selected science programs will allow astronomers to directly image exoplanets around other stars, utilizing JWST's coronagraphic masks to block out starlight and look at surrounding debris disks, clouds of rock and dust emblematic of the early stages of planetary formation. JWST's infrared spectrometers will view Jupiter-sized planets like WASP-39b and WASP-43b to measure the composition and dynamics of their atmospheres, observations NASA says "will help guide observing strategies for smaller, mostly rocky and more Earth-like super-Earths, wh ere atmospheric composition may give hints of a planet's potential habitability."

Another team of astronomers will turn JWST's optical and infrared gaze toward globular clusters orbiting the Milky Way and a relatively nearby galaxy to take what amounts to a stellar census. The imagery will allow scientists to count the stars in each cluster, and determine their ages, yielding insights into the history of galaxies in the Milky Way's neighborhood, and the wider cosmos, according to Daniel Weisz, an astronomer at the University of California – Berkeley.

"For studies of very faint stars in the Milky Way – our own galaxy – the JWST is going to be phenomenal," Weisz said in a statement. "The telescope will do roughly in its five- to 10-year mission what Hubble has done in its 25-year mission for local galaxies."


Artist's concept of an alien solar system. Credit: NASA

JWST's primary mirror spans 21.3 feet (6.5 meters) in diameter, nearly three times bigger than the Hubble Space Telescope.

Scientists investigating the formation and evolution of the universe will peer back in time using the first-of-their-kind capabilities to debut with JWST.

Steven Finkelstein, a professor of astronomy at the University of Texas at Austin, leads a campaign to extend a deep galactic survey previously conducted with Hubble, overlaying the earlier optical observations with new, deeper infrared imaging sensitive to the light-stretching effects of the expansion of space.

"We will discover the most distant galaxies ever seen — galaxies that were literally invisible to Hubble," Finkelstein said in a statement.

With JWST, astronomers should resolve galaxies as they existed 13.4 billion years ago, 3 percent of the universe's current age, according to a University of Texas press release. Observing such distant galaxies in infrared light will help researchers understand how the earliest stars formed, then assembled into galaxies and ever-larger cosmic structures.

"This will be the first time anyone has had access to this brand new telescope that is in some ways 100 times better than Hubble," Finkelstein said. "This telescope will reveal enormous truths the moment we turn it on."

Astronomers with early observing time on JWST will also turn the telescope to look at galactic clusters, using their immense gravity as lenses to see more distant galaxies lurking behind them.


This Hubble Space Telescope image shows the MACS J0717.5+3745 galaxy cluster, one of JWST's first scientific targets. Credit: NASA, ESA, and H. Ebeling (University of Hawaii)

Closer to home, Jupiter and its moons will be a subject of JWST's focus early in the mission to demonstrate the observatory's scientific promise for solar system research.

"We will see if we can image the rings and get rid of the scattered light fr om Jupiter, which pushes the telescope's limits and really tests the capabilities of JWST," said Imke de Pater fr om the University of California – Berkeley.

JWST will also observe Jupiter's auroras, the volcanic eruptions on Jupiter's moon Io, and search for an atmosphere and potential icy plumes on Ganymede.

It takes long-term planning to develop, propose and defend ideas to use valuable time on a costly observatory like JWST.

"With the telescope's five-year lifetime, we need to use it very efficiently to maximize the return," said Weisz, the UC-Berkeley astronomer using the telescope to study stars in nearby galaxies. "The early release science program is supposed to produce science-enabling results within five months of the observations, which in the astronomy world is basically yesterday."

The astronomical targets announced last month were revealed several months after officials unveiled the JWST investigations granted to science teams with guaranteed observing time.

Those studies include observations that fall within some of the same themes as the early release science, such as ancient galaxies that formed just after the Big Bang, the birth and evolution of stars and planets, and our own solar system, particularly the outer planets and the search for the chemical fingerprints of potential life on Saturn's moon Enceladus.

A more extensive "guest observer" program is also in the works to give astronomers not directly involved in the telescope's development wider access to the observatory in the 2020s.
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http://tass.ru/kosmos/4800476
ЦитироватьСША намерены вывести в космос три новых телескопа в ближайшие десять лет
ВАШИНГТОН, 11 декабря. /Корр. ТАСС Александр Пахомов/. США намерены вывести в космос три новых телескопа в ближайшие десять лет с целью поиска потенциально пригодных для жизни планет. Такими планами американского космического ведомства поделился с конгрессменами Томас Зурбукен, помощник директора NASA, ответственный за научные миссии.
"Кроме того, NASA в январе прошлого года инициировало разработку концепции космического телескопа следующего поколения, который предполагается вывести на орбиту в 2030-е годы", - подчеркнул он на слушаниях, прошедших в конце минувшей недели в подкомитете по космосу Палаты представителей Конгресса США.
Зурбукен напомнил, что в настоящее время продолжает совершать открытия космическая обсерватория Hubble, доставленная на орбиту в 1990 году и "позволившая расширить представление о Вселенной и нашем месте в ней".
Поиск экзопланет
Основываясь на информации, полученной с помощью Hubble и других телескопов, эксперты NASA ранее высказали 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".
Планы запусков
"В марте 2018 года в космос должен быть выведен аппарат под названием Transiting Exoplanet Survey Satellite (TESS, Спутник по исследованию планет, проходящих перед своей звездой - прим. ТАСС), - рассказал Зурбукен. - Сейчас продолжаются его сборка и испытания компонентов и оборудования. Задача TESS - выявить ближайшие к нам планетные системы, по своим параметрам в наибольшей степени сравнимые с нашей Солнечной системой. Ими в дальнейшем будут заниматься телескопы, которые выведут на орбиты вслед за TESS".
"Один из них - James Webb, - продолжил помощник директора. - Его запуск намечен на март-июнь 2019 года. Это будет наиболее мощный космический телескоп, когда-либо созданный человеком".
"Затем в космос отправится Wide Field Infrared Survey Telescope (WFIRST, Широкоугольный инфракрасный исследовательский телескоп - прим. ТАСС)", - отметил Зурбукен.
По его словам, WFIRST сможет наблюдать в 100 раз больший участок пространства, чем Hubble. Ученые NASA рассчитывают получить с его помощью информацию не только об экзопланетах, но и о так называемой темной материи, о строении и эволюции Вселенной. Запуск телескопа WFIRST запланирован на 2024-2026 годы.
Что касается концепции телескопа следующего поколения, то на слушаниях было отмечено, что один из четырех рассматриваемых проектов - Large UltraViolet, Optical, and InfraRed observatory (LUVOIR, Большая ультрафиолетовая оптическая инфракрасная обсерватория) с диаметром зеркала 15 метров. Ожидается, что решение будет принято в 2019 году, а вывод в космос может состояться в 2035 году.
На смену Hubble
Именно James Webb должен заменить Hubble. Первоначально предполагалось, что это произойдет еще в 2013 году. Однако реализация проекта, в который уже вложено около $8 млрд, сильно отстала от графика.
В конце сентября NASA в очередной раз объявило о переносе даты запуска новой обсерватории - с октября 2018 года на весну 2019 года, обосновав это сложностью испытаний ее конструкции и оборудования.
На телескопе, названный в честь Джеймса Уэбба, руководителя программы "Аполлон", позволившей человеку побывать на Луне, установлено зеркало диаметром 6,5 метра, оптические приборы и инфракрасные датчики, которым предстоит работать в открытом космосе при температуре примерно минус 233 градуса по Цельсию.
Обсерваторию предполагается вывести далеко за Луну на орбиту, находящуюся на расстоянии примерно 1,6 млн км от поверхности Земли. В течение шести месяцев вся бортовая аппаратура будет проверена, и James Webb приступит к изучению Вселенной. Срок его эксплуатации рассчитан на 10 лет.
Большие затраты
Ряд конгрессменов, в частности, председатель подкомитета по космосу Брайан Бэбин, выразил беспокойство по поводу перерасхода средств при реализации программ создания новых орбитальных обсерваторий. "Предполагается, что эти три телескопа обойдутся нам по меньшей мере в $12,4 млрд, что составляет примерно 50% всех средств, выделяемых NASA на астрофизические проекты, - указал он. - Хотя для NASA важно расширять технологические границы исследований, так же важно осуществлять финансовый контроль над проектами".
В качестве примера он привел программу разработки телескопа James Webb. "Ожидается, что в конечном счете на него будет затрачено $8,8 млрд, что на 78% больше, чем первоначально называлось при утверждении проекта", - заметил Бэбин.
По его словам, расходы на TESS составят $336 млн, на WFIRST - от $3,2 млрд до $3,4 млрд.
На начавшийся 1 октября 2018 финансовый год Конгресс выделил на деятельность NASA $19 млрд.

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ЦитироватьHighbay Integration Progress of NASA's James Webb Space Telescope (JWST)

 Northrop Grumman

Опубликовано: 19 дек. 2017 г.

Watch a time lapse video of the integration progress of NASA's James Webb Space Telescope (JWST) in Northrop Grumman's Redondo Beach facilities! Northrop Grumman is proud to lead the industry team building JWST. This revolutionary observatory is the largest telescope built for space and the most powerful infrared telescope ever made. It is the scientific successor to the Hubble Space Telescope. The Webb telescope will travel 1 million miles from earth and look back over 13.5 billion years, providing images of the first galaxies formed and observing unexplored planets around distant stars. The breakthrough technology developed for the Webb Telescope will expand our understanding of the universe, rewrite textbooks and inspire a future generation of engineers and scientists.
https://www.youtube.com/watch?v=abJ_g1nzSbchttps://www.youtube.com/watch?v=abJ_g1nzSbc (4:00)

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https://www.nasa.gov/feature/goddard/2017/webb-telescopes-silver-and-gold-decorations
ЦитироватьDec. 21, 2017

Webb Telescope's "Silver and Gold Decorations"

You won't catch NASA's James Webb Space Telescope saying "Bah, humbug!" to seasonal festivities.

Like in the classic holiday song, Webb's "silver" sunshield and "gold" mirrors shimmer brightly in this image mashup. These are more than decorations for Webb, and their worth is measured by the scientific discoveries the telescope will make.
Спойлер

This image mashup highlights two achievements NASA's James Webb Space Telescope had in 2017. In October, Webb's sunshield was tensioned for the first time at Northrop Grumman Aerospace Systems in Redondo Beach, California. In November, Webb's combined optics and science instruments completed cryogenic testing inside Chamber A at NASA's Johnson Space Center in Houston.
Credits: NASA/Chris Gunn

Webb telescope, or Webb, is NASA's upcoming infrared space observatory, which will launch in 2019. The two photos that compose this image highlight two important achievements Webb had in the latter part of 2017.

In early December, Webb's combined optical element and science instruments emerged fr om Chamber A at NASA's Johnson Space Center in Houston, where it successfully completed cryogenic testing. During testing, scientists and engineers at Johnson put Webb through a series of tests designed to ensure the telescope functioned as expected in an extremely cold, airless environment akin to that of space.

Webb's primary mirror consists of 18 beryllium mirror segments, and each segment is gilded with a tiny amount of gold — about a golf ball's worth for the entire mirror. Each mirror segment was gilded through a process called vacuum vapor deposition, wh ere a miniscule amount of the precious metal is vaporized and deposited on each segment inside of a vacuum chamber.

In October, Webb's tennis court-sized, five-layer, deployable sunshield was fully tensioned at Northrop Grumman Aerospace Systems in Redondo Beach, California. During the tensioning process, engineers at Northrop carefully and deliberately stretched the sunshield to its fully deployed position. This was the first of several tensioning sessions the sunshield will undergo.

Though the sunshield appears silver, each layer is actually coated with reflective aluminum. The sunshield is composed of what are essentially sheets of special plastic that maintain their integrity at extreme temperatures. Each sunshield layer is only about 1/1000th of an inch thick.

These two halves of the James Webb Space Telescope observatory — Webb's combined science instruments and optics, and its combined spacecraft bus and sunshield (called the spacecraft element) — will be integrated at Northrop Grumman in 2018. Webb will launch from Kourou, French Guiana in 2019.

Webb's eventful year

These most recent accomplishments were among several Webb had for 2017. In March, the telescope's combined optics and science instruments completed acoustic and vibration testing at NASA's Goddard Space Flight Center in Greenbelt, Maryland, before moving to Johnson for cryogenic testing.

"This was a pivotal year for Webb. With launch environment and cryogenic testing completed, we have demonstrated our science payload functions as planned," said Eric Smith, program director for Webb telescope at NASA. "In 2018, the telescope will meet up with the other iconic and now completed component of Webb, its sunshield and spacecraft, to form the observatory."

On the scientific front, September saw worldwide participation from the science community for the Director's Discretionary Early Release Science (DD-ERS) program, and in November, NASA announced the proposals it sel ected for the DD-ERS program. The science observations for these proposals will be completed within the first five months of Webb's science observations.

"Though there is still observatory testing ahead of us, the response this year fr om the science community for Early Release Science shows that there are exciting questions already queued up for Webb to answer," Smith said.

The James Webb Space Telescope is the world's premier infrared space observatory of the next decade. A barrier-breaking mission for engineers and astronomers, 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 (ESA), and the Canadian Space Agency (CSA).

For more information about the Webb telescope visit: www.webb.nasa.gov or www.nasa.gov/webb

By Eric Villard
NASA's Goddard Space Flight Center
[свернуть]
Last Updated: Dec. 21, 2017
Editor: Lynn Jenner