James Webb Space Telescope

I was hoping somebody might be able to answer this question. The JWST seems very delicate. Is NASA planning to open and test it in low Earth orbit before sending it to that Lagrangian point 4 times the distance of the Moon? I can imagine something might jam and not open so that it might be nice to deal with these problems closer to Earth. On the other hand, I can imagine it might be too delicate to move to the Lagrangian point after it is opened-up.

reply to post by cloudyday



That is funny. Where I work we have a manager named James Webb.

Originally posted by Turkenstein
reply to post by cloudyday

 

That is funny. Where I work we have a manager named James Webb.

Is he also delicate and potentially prone to a breakdown?

reply to post by cloudyday
Here is a nice little docu that answers your question.

Originally posted by Atzil321
reply to post by cloudyday

 

Here is a nice little docu that answers your question.

Thanks for the video. It looks like they open-up at the Lagrangian point. Hope it works as planned.

There have been several updates since this post. I will try to keep it in order.

So this ATS thread asked: So just how powerful will the James Webb Space Telescope be?

Lockheed Martin delivered the camera potion to NASA's Goddard Space Center a couple years ago but integration with the other equipment happened earlier this month.

According to Lockheed Martin, the Near Infrared Camera (NIRCam) instrument exceeded requirements during Integrated Science Instrument Module (ISIM) testing and will now be integrated into the telescope's instrument cluster for combined testing.

Built by Lockheed for NASA and the University of Arizona, NIRCam acts as the primary science instrument and imager for the JWST and was delivered to NASA in March 2014 for installation and testing in the ISIM. It covers the infrared wavelength range of 0.6 (the edge of the visible spectrum) to 5 microns (the near infrared) and its focal plane assemblies consist of 40 million pixels that operate at 35 Kelvin.

In addition, NIRCam acts as the telescope's primary mirror-alignment sensor, which keeps the 18 individual, adjustable mirror segments aligned, so it comes under the heading of indispensable

Source: gizmag - Lockheed Martin component brings Webb Space Telescope into focus

And the mirrors had their protective covers removed in clean room just yesterday, April 26, 2016.

And with a width of 6.5m, JWST's will have roughly seven times the light-collecting area of Hubble's mirror.

It is so big in fact that it must be capable of folding. Only by turning the edges inwards will the beryllium segments fit inside the telescope's launch rocket.

The observatory is currently under construction at the US space agency's Goddard Space Flight Center in Maryland.

Source: BBC News - James Webb's mirror is revealed (with pics)

From the BBC report, here are the project's next steps.

Shortly, the secondary mirror,... will be collapsed into a flat configuration.

Then, the whole edifice will be flipped 180 degrees. This will permit the engineering team to attach JWST's instruments behind the main mirror.
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Once the integration of mirror and instruments is complete, the telescope will be sent for environmental testing. It will be shaken and blasted with sound to mimic the rough rocket ride to orbit.

Assuming that goes well, the whole train - mirror and instruments - will ship to Nasa's Johnson Space Center in Texas for some final deep-chill testing.

This will be conducted in the giant cryo-vacuum chamber built to accommodate the 1960s Apollo hardware.

Once that work is done, engineers must attach the spacecraft bus, which incorporates elements such as the flight computers and communications system. Finally, James Webb will be given an immense deployable visor - the structure that will shield its delicate observations from the Sun's light and heat.

"Shaken and blasted with sound"? More like, "Let's rock and roll!"

Direct NASA link explaining the mirror: The Primary Mirror has a detailed description of each piece and the entire assembly process. Contains more pics and a video.

The expected launch is targeting October, 2018.

Ooooh! They have two webcams up at Goddard Space Center where JWST is at. They auto-load every, thirty? seconds looks like. And there is a cool photo of the mirror deployed.

Link: NASA, James Webb Space Telescope - web cams on home page

[T]wo dozen engineers and technicians successfully installed the package of science instruments of the James Webb Space Telescope into the telescope structure. The package is the collection of cameras and spectrographs that will record the light collected by Webb's giant golden mirror.

Inside the world's largest clean room at NASA's Goddard Space Flight Center in Greenbelt, Maryland, the team crane-lifted the heavy science instrument package, lowered it into an enclosure on the back of the telescope, and secured it to the telescope.
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Before the procedure, the engineers and technicians had trained with test runs, computer modeling and a mock-up of the instrument package. This is a critical mission operation.

"This is a tremendous accomplishment for our worldwide team," said John Mather, James Webb Space Telescope Project Scientist and Nobel Laureate. "There are vital instruments in this package from Europe and Canada as well as the US and we are so proud that everything is working so beautifully, 20 years after we started designing our observatory."

Source: Phys.og, May 25, 2016 - Science instruments of NASA's James Webb Space Telescope successfully installed

From the previous post they are now going to rock and roll! (Shake it with sound). After a few more checks the whole things will go to the cold room and be further tested there.

Successful integration! Good job! (I missed watching on the web cams...)

Space-based observations from telescopes like the Hubble Space Telescope have amazed us for decades and the James Webb Space Telescope is only a couple of years away from launch. Recently, we have seen amazing discoveries of planets outside our solar system and the detection of gravitation waves. This is just the beginning.
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Kepler’s successes in hunting exoplanets will continue with the launch of the Transiting Exoplanet Survey Satellite (TESS) in 2017 and be augmented by the capabilities of the James Webb Space Telescope (JWST), the Wide Field Infrared Space telescope (WFIRST), and ground-based telescopes such as the Large Synoptic Survey Telescope (LSST). The LSST may be able to peer into the atmospheres of these exoplanets and conduct spectroscopy to determine the composition of their atmospheres.

Souce: SpceRef.com, July 12, 2016 - Chairman Smith's Opening Statement on Astronomy, Astrophysics, and Astrobiology Hearing.

This is the written transcript from the Chairman's opening statement he was to deliver to the House sub-committee. The upcoming missions are nice to see as managers (the House is no different than other managerial entities) tend to only see the year-to-year view. Every now and then they need to be reminded of long range goals (Vision, as they like to call it). And while Hubble is nice, the LSST sounds way better! The ability to measure another planet's atmosphere? How cool is that.

Ah, just a shame they have to go pander to the House for funding. A scientist asking a lawyer for money... what could go wrong with that? I forgot, no politics. Enough of that around this place these days.

Nice to see the JWST still being referenced and "put out there" to keep in back of everyone's mind.

The cooler will chill one of the Webb telescope's four instruments, called the Mid-Infrared Instrument, or MIRI, which will also study other stars, exoplanets and galaxies.
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MIRI will be the coldest instrument onboard the telescope, operating at... temperatures of no more than 6.7 degrees above absolute zero, or minus 448 degrees Fahrenheit. Why so cold? MIRI sees what is known as mid-infrared light, which is given off by objects at around room temperature. Desks, people and the air we breathe, for example, are aglow with mid-infrared light that we can't see with our eyes. Specialized instruments like MIRI are designed to pick up this mid-infrared glow, but they must be chilled to avoid background infrared light that can drown out what astronomers want to see.
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"The instrument has to be cold enough to not detect itself," said Ressler, explaining that the instrument gives off its own heat. Moreover, MIRI’s mid-infrared detectors, which convert light into electrical signals the way a camera chip inside a cell phone does to take photos, need to be chilled to less than 7 degrees above absolute zero to even work right.
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Engineers first fitted the compressor and their electronics into a special cold chamber and tested it, then they vibrated the compressor to mimic the effects of a rocket launch, and finally tested it once again in the cold chamber, checking-out its full range of performance.

The results showed that the device is twice as efficient as required. "If a lot of extra unanticipated heat is generated by the telescope, we can take care of it," said Sukhatme.

Source: NASA, Webb Telescope, June 13, 216 - How Cold Can You Go? Cooler Tested for NASA Telescope.

Missed this when it hit the site last month. So this has been through the cold test and the vibration test and passed! No word on if the JWST has been through the same tests. Nothing much exciting on the web cams either. The cold temp also allows the JWST to see "further back" in time. The article states that at the Lagrange point the JWST will operate at 40 °K so MIRI requires the extra cooling.

Nice to progress on this story!

Taking a "before" optical measurement of the telescope's deployed mirror is crucial before the telescope goes into several stages of rigorous mechanical testing. These tests will simulate the violent sound and vibration environments the telescope will experience inside its rocket on its way out into space.
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Webb has been designed and constructed to withstand its launch environment, but it must be tested to verify that it will indeed survive and not change in any unexpected way. Making the same optical measurements both before and after simulated launch environment testing and comparing the results is fundamental to Webb's development, assuring that it will work in space...
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The Center of Curvature test measures the shape of Webb's main mirror by comparing light reflected off of it with light from a computer-generated hologram that represents what Webb's mirror ideally should be.

Phys.org, Nov. 2, 2016 - NASA completes Webb Telescope Center of Curvature pre-test.

So this is a baseline test of the mirror prior to the sound test (see above). Then will come the sound test. Then they will retest the mirror again. And it uses a hologram! That is pretty cool! That should make interference patterns stand out when directly compared.

Get ready to rock and roll JWST! Nice to see progress in science happen. Even if I am a bit impatient about the process.

A Jet Propulsion Laboratory engineer says he was detained by U.S. Customs and Border Protection in Houston during President Trump’s travel ban and pressured into giving agents access to his NASA-issued phone.

Sidd Bikkannavar detailed his detainment in a public Facebook post two weeks ago that has since been removed, according to a cache of the page.

“Just to be clear — I’m a US-born citizen and NASA engineer, traveling with a valid US passport,” Bikkannavar wrote on Facebook. “Once they took both my phone and the access PIN, they returned me to the holding area with the cots and other sleeping detainees until they finished copying my data.”

...

NASA provided a new device and a new phone number, according to the Facebook post.

San Gabriel Valley Tribune, Feb. 13, 2017 - Jet Propulsion Laboratory employee detained at airport during Trump’s travel ban, NASA-issued phone probed.

Well, that is what happens when politics and science mix. A foreign sounding name is enough to trigger a "routine sample" with the added indignity of having your government issued phone copied! This occurred 4 days after the President's travel ban (funny how that sounds very close to "towley ban" from South Park!)

He said he contacted JPL legal in the article. Not sure what can be done. Anybody asking me for a PIN for my device is a thief as far as I would say. Just my opinion and might be different facing armed men at a security check point.

Anyway, we are the verge of great discoveries in universe while mired down here on the surface with this stuff.

End of the line for the Goddard Space Flight Center.

The Webb telescope will be shipped to Johnson [Houston, Texas] for end-to-end optical testing in a vacuum at its extremely cold operating temperatures. Then it will continue on its journey to Northrop Grumman Aerospace Systems in Redondo Beach, California, for final assembly and testing prior to launch in 2018.

The James Webb Space Telescope is the world’s most advanced space observatory. This engineering marvel is designed to unravel some of the greatest mysteries of the universe, from discovering the first stars and galaxies that formed after the big bang to studying the atmospheres of planets around other stars. It is a joint project of NASA, ESA (the European Space Agency) and the Canadian Space Agency

NASA.gov, May 1, 2017 - NASA’s Webb Telescope Completes Goddard Testing, Heading to Texas for More.

It was fun looking in occasionally to see work being done. The photos of the mirrors unfolded are spectacular. Seeing all parts put on the frame from individual assemblies was cool. This was very public and thanks to Goddard for putting in the web cams!

Congrats to Goddard and their teams!!

a reply to: TEOTWAWKIAIFF

Let's hope the Ariane 5 does its job. Can you imagine how awful a launchpad failure will be?!

a reply to: Kandinsky

Pshaw!! Say no such thing!

After all this work and years... I would probably cry.

Especially with another year to wait before launch.

originally posted by: Kandinsky
a reply to: TEOTWAWKIAIFF

Let's hope the Ariane 5 does its job. Can you imagine how awful a launchpad failure will be?!

That is my concern too. Hopefully North Korea won't try payback by jamming the rocket Electronics.

a reply to: TEOTWAWKIAIFF

I know! I was idly reading through your post and links and the thought popped in there. It'd be worse than the UK Mars mission that failed when it got there. Truly catastrophic and thankfully against the odds.

a reply to: carewemust

You never know. Anything is possible these days

ETA - I look at what these guys are achieving and how a few ATSers insist it's all fake. How can anyone read about this and then brush it all off with a four-letter F-word?

a reply to: Kandinsky

"And we have lift off of the.....well it WAS the James Webb telescope...."

I think that would only rank behind the three accidents that cost them astronauts in terms of disaster.

a reply to: Zaphod58

God yeah! We'd feel like the Russians did with their numerous failures and Moon misses.

It's like the life work of scores of scientists all gone for nothing.

a reply to: Kandinsky

I was watching Nat Geo's, The 90s, The Last Great Decade?

Watching Challenger go up still kicks me in stomach!

My vote is, "No to rocket failures"! Wikipedia say says Ariane 5 has 77 launches with no failures. But yeah, the fickle gods of fate and what have you.

Wikipedia: List of Ariane launches.