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James Webb Space Telescope, information, updates and discussion
Redstone
post Aug 23 2005, 02:01 PM
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The manufacture of the JWST mirror blanks has now been completed.

Despite this milestone, the fate of JWST is still somewhat precarious, because although the scientific bang from the telescope is expected to be huge, the bucks required have increased to a staggering $4.5 billion. A Space.com article on the squeeze in NASA's space-based astronomy plans gives some background.

The JWST home page can be found here.

The Space Telescope Science Institute, which runs Hubble, also has a site here. As does ESA.
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djellison
post Aug 23 2005, 02:10 PM
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Just how does it end up costing $4.5B ( which will become $5B I'm sure)

That's just - wow. That's TEN Mer's.

TEN

I'm not saying "drop the scope, build Ten MER's" - but even the challenge of getting that mirror light enough, and deploying accurately enough surely cant cost $4.5B

Doug
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Redstone
post Aug 23 2005, 02:42 PM
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Well, a 6.5m telescope is pretty big even on the ground. And the plan is to send it to L2, not LEO, so with no repair capability, it has to be REALLY well designed, with huge redundancy and margin etc. Plus, the thing weighs nearly seven tonnes.

A little more info at this New Scientist article.

Back in 2003, it was projected to cost $2.5 billion. I'll see if I can find some more info on what is driving up the cost.
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Bob Shaw
post Aug 23 2005, 03:03 PM
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The JWST has always struck me as being a prime example of why men in space (or at least very capable robonauts) are a good idea. The mechanical requirements of unfolding those mirror segments and the sunshade, plus the inevitable limits on attitude-control and instrumentation really do demand some up-close-and-personal TLC. Hubble never really needed men (it was launched 'built') and the upgrades were always the jam on the cake (OK, they got the mirror wrong, and that fix *did* need men, but you can't say that such activities were a part of the rationale behind Hubble and the Shuttle - it was sheer luck that after a really bad start something could be done at all!). JWST, however, is exactly the sort of structure which could do with a quick tap from a guy with a rubber mallet when the main wossisname joint flange sub-assembly secondary cotter-pin stiffens up!

Personally, I'd put JWST on the back burner until it can be man-tended, and spend the money in the meantime on a series of state-of-the-art but disposable Hubbles II, III and IV. JWST smells too strongly of too many eggs in one basket for me, and after the Galileo antenna I'd as soon not have to trust my faith in interplanetary origami.


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dilo
post Aug 23 2005, 09:22 PM
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4.5 billion is a lot. If I'm not wrong, this is 2 B$ above Hubble, and still surpassing it even considering the cost of shuttle servicing missions.
How is possible? clearly, the aveniristic technology require strong investment... but consider that this will have many applications and can be an investment for future space telescopes!
[/quote]


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Redstone
post Aug 26 2005, 09:50 PM
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It seems JWST is safe from outright cancellation for the moment. A New Scientist article has some detail on how the project hopes to rein in the budget for JWST. Part of it is limiting testing. Scary. The other part is reducing the amount of polishing of the mirrors which will greatly slow down JWST's ability to image in the optical part of the spectrum. JWST was always billed as a near IR telescope, but the lack of any overlap with Hubble is going to hurt.

Launch is also delayed, probably to 2013.
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antoniseb
post Aug 26 2005, 10:31 PM
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QUOTE (Redstone @ Aug 26 2005, 04:50 PM)
JWST was always billed as a near IR telescope, but the lack of any overlap with Hubble is going to hurt.


The overrun is about a billion dollars (so far), and the reduced mirror polishing will save $150M. They've got a few other cost cutting things to do, or somehow get more funding.

Does anyone know how much of the budget is a one time expense to do research on electro-mechanical devices that work at near absolute zero temperatures? I am kind of curious to know where the money for this project has gone, as it will give some guidance for future large space telescopes such as SIM and Terrestrial Planet Finder.
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Bob Shaw
post Aug 26 2005, 10:39 PM
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IMHO, JWST should be put on hold, and then back out to competition - it's just going the way of the ISS, descoped and over budget, when Burt Rutan and Co would just build the damn thing, and hit it with a hammer as required until it was the right shape. If JWST fails, then (near) optical space astronomy goes down the tubes, period.

Failing that, a bunch of throwaway Hubbles (maybe with a He replenishment capability, but that's all).

Really, it's nuts to NOT make JWST man-tended!


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Redstone
post Oct 9 2005, 04:16 PM
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First JWST mirror segment delivered for polishing.

Northrup press release.

QUOTE
The mirrors will be polished to tolerances as tight as 20 nanometers, or less than one millionth of an inch.

After initial polishing, the segments will be tested at roughly minus 400 degrees Fahrenheit (near absolute zero) in a cryogenic test chamber at NASA's Marshall Space Flight Center in Huntsville, Ala., and returned to Tinsley for further refinement and polishing. The entire polishing process takes about two-and-a-half years.

blink.gif No wonder this telescope costs a fortune.
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Guest_BruceMoomaw_*
post Oct 9 2005, 10:07 PM
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"Really, it's nuts to NOT make JWST man-tended!"

Not when you consider that both its sensitivity and its available observation time are tremendously reduced if you put it anywhere near the radiated warmth of Earth. Considering that, it's still more scientifically cost-effective to put it at the Earth-Sun L2 point, even though it's beyond range of human repairmen. (Keep in mind that, once the design work for the first one has been done, the cost of an identical replacement would be considerably less.)
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SigurRosFan
post Oct 9 2005, 10:24 PM
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"The James Webb Space Telescope is a large, infrared-optimized space telescope scheduled for launch no earlier than June 2013."

http://www.jwst.nasa.gov/


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Redstone
post Nov 21 2005, 01:53 PM
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Some more detail on the JWST delay to 2013. The article also says that the telescope will not be "descoped" to any great degree. Only some testing and instrumentation for low priority science will be removed. Cost is still $4.5 billion, but now has less risk, and a more even funding profile. And launch is likely to be on an Ariane 5, with a launch deal set for 2006.

With HSM 4 now more and more likely, this delay doesn't bother me so much. HST will last that long, and there will still be overlap between the two observatories.

And SIM, which is seen as a casualty of the JWST overruns, has been giving a funding boost by Congress, and is on track for a 2012 launch, according to this story.
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Guest_AlexBlackwell_*
post Mar 8 2006, 08:56 PM
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I moved this from a thread I started to this one. Thanks to ljk4-1 for pointing it out to me.

I apologize if there is already a thread on JWST; I didn't take the time to look (very hard). However, if there isn't, I'll kick-start it by pointing out Tony Reichhardt's excellent news article in the March 9, 2006, issue of Nature:

US astronomy: Is the next big thing too big?
Tony Reichhardt
Nature 440, 140-143 (2006).
doi:10.1038/440140a
Full Text

Excerpt:

QUOTE
So no one is denying that the JWST will be a first-rate telescope, perhaps even a revolutionary one. Just last August an independent assessment team charged by the project to review the telescope's science potential reported that "the scientific case for the JWST mission has become even stronger" since the Decadal Survey's endorsement in 2000. But what of its expense? NASA's latest budget puts the project's price tag, including $1 billion for a decade's worth of operations, at $4.5 billion. That's more than the entire annual research and development budget of the National Science Foundation; it represents more than $1 million for each full member of the American Astronomical Society.


Nature also has an editorial ("Refocusing NASA's vision") on the subject in the same issue. Following is an excerpt:

QUOTE
It is now clear that when NASA first requested funds for a Next Generation Space Telescope a decade ago, the project's advertised price of under $1 billion was little more than a fiction. But it was a fiction that the space agency, the Congress and many in the astronomy community wanted to believe.


And, of course, there's the recent NASAWatch/Spaceref article "JWST Talking Points."
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Guest_BruceMoomaw_*
post Mar 14 2006, 03:07 AM
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My attempt to attach this article failed; it overloaded available space on this site. I'll have to do a summary of it later -- it makes a great many important points about the current space science proram.
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Guest_BruceMoomaw_*
post Mar 14 2006, 03:47 AM
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Particularly interesting quotes from the article:

(1) "At the beginning of the millennium, US astronomers thought that their most-wanted project would cost $1 billion...NASA's latest budget puts the project's price tag, including $1 billion for a decade's worhthof operations, at $4.5 billion. That's more than the entire annual research and development budget of the National Science Foundation; it represents more than $1 million for each full member of the American Astronomical Society." Which, I think, makes my point again about the low cost-effectiveness of most space science, and the immense difficulty it would have competing for government funding in any honest competition with other kinds of scientific research.

(2) One part of the problem DOES seem to be NASA HQ's fault. "A delay in the government's decision to move from a US launcher to the Ariane added an estimated $300 million as highly paid engineers were unable to move forward until they knew which rocket they were designing for. The situation is particularly embarrassing given that the cost of delaying the decision ended up being greater than the cost of the launch." Ah, the rationality of government. Still, this is only 1/12 of the total cost rise.

(3) As for the other causes of the cost underestimate: "The Decadal Survey guessed the cost as $1 billion. Studies in the mid-1990s had pegged the price as between $500 million and $1 billion. These were based on the hope -- unfulfilled, as it happened -- that the Webb Telescope might take advantage of advances in building low-cost spaceraft developed by the military."

However: "Garth Illingworth of UC-Santa Cruz, who chaired the 1990 panel [which much more acurately predicted its current cost], chalks the anomalously low estimates from the 1990s up to a 'lack of reality' inherent in the 'faster, better, cheaper' philosophy of Dan Goldin...Reinhard Genzel of Germany's Max Planck Institute for Extraterrestrial Physics in Garchning says it was clear at the time that a $500 million estimate for the Webb Telescope was a 'political price'...

"Today, Illingworth inveighs against the 'extraordinarily bad, artificial cost estimates' of the Goldin era. But the 2000 Decadal Survey seems to have been happy to accept them. The world of big science is well used to projects being lowballed -- a process that gets schemes started on the basis of a low-cost estimate, with the implicit hope that by the time the true costs are known inertia and vested interests will make it impossible to pull out. Lowballing is not a practice anyone would like to defend on principle, but histories like the Hubble's show it can work." That is, our old friend the Camel's Nose again -- exactly the same technique NASA used to get Shuttle and Station funded.

(4) Where Hubble is concerned: "[Hubble project scientist Robert] O'Dell recalls that in 1972, Hubble's total price including its first year of operations was projected to be...$1 billion in today's prices. According to Robert Smith, a historian at Canada's Univ. of Alberta who wrote a political history of the telescope...'the development cost of Hubble to date is certainly more than $4 billion.'

"NASA's Eric Smith adds that when new instruments and operating expenses are added, that comes to $9 billion. This doesn't include the cost of four space shuttle servicing missions to Hubble, and a fifth being planned -- the cost of a shuttle launch can be put at about $500 million. All in all, building, launching, using and refurbishing Hubble has probably been the most expensive undertaking ever made in the name of pure science; the mission is still, remarkably, costing over $300 million a year." (And that's ignoring the fact that the true cost of each Shuttle mission, using honest accounting, is over $1 billion!)

(5) Charles Beichman of JPL, a leading light of the cancelled Terrestrial Planet Finder mission...thinks that the Webb Telescope will be 'a fine machine. It will do fantastic science.' In fact, he is on one of the instrument teams. But when he goes to professional meetings, he sees more young astronomers attending sessions on planet-finding than on Hubble or the Webb Telescope." Of course, Beichman couldn't POSSIBLY be a biased witness in this matter. Heavens, no. But I do find it at least plausible that the examination of other solar systems is considered, on balance, more romantic -- and thus more interesting -- by genuine astronomers than cosmology or other fields of space astronomy are, just as it is by the nonscientific public.

Still, as the article says, "anyone who doesn't realize that TPF would be costlier than the Webb Telescope is dreaming." I shudder to think what the real cost of THAT endeavor will end up being -- which is why I have no objection at all to protractedly deferring it until Kepler and/or SIM have given us the initial census of the frequency of potentially habitable planets which we need to make even the most basic decisions as to the design of TPF.

In summary, it is very hard to blame the Webb Telescope problem itself on NASA HQ -- although of course the cuts in space science spending as a whole can be blamed on the hypertrophied (or, to be more accurate, metastasized) manned space program. But where Webb's tendency to hog most of whatever the actual space astronomy budget turns out to be is concerned, I think that space astronomers -- to quote Popeye the Sailor -- "buttered their bread and now they've got to sleep in it."
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