James Webb Space Telescope, information, updates and discussion |
James Webb Space Telescope, information, updates and discussion |
Aug 23 2005, 02:01 PM
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Member Group: Members Posts: 134 Joined: 13-March 05 Member No.: 191 |
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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Aug 23 2005, 02:42 PM
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Member Group: Members Posts: 134 Joined: 13-March 05 Member No.: 191 |
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 $2.5 billion. I'll see if I can find some more info on what is driving up the cost. |
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Aug 23 2005, 03:03 PM
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Senior Member Group: Members Posts: 2488 Joined: 17-April 05 From: Glasgow, Scotland, UK Member No.: 239 |
The JWST has always struck me as being a prime example of why men in space (or at least very capable robonauts) are a good idea. The mechanical requirements of unfolding those mirror segments and the sunshade, plus the inevitable limits on attitude-control and instrumentation really do demand some up-close-and-personal TLC. Hubble never really needed men (it was launched 'built') and the upgrades were always the jam on the cake (OK, they got the mirror wrong, and that fix *did* need men, but you can't say that such activities were a part of the rationale behind Hubble and the Shuttle - it was sheer luck that after a really bad start something could be done at all!). JWST, however, is exactly the sort of structure which could do with a quick tap from a guy with a rubber mallet when the main wossisname joint flange sub-assembly secondary cotter-pin stiffens up!
Personally, I'd put JWST on the back burner until it can be man-tended, and spend the money in the meantime on a series of state-of-the-art but disposable Hubbles II, III and IV. JWST smells too strongly of too many eggs in one basket for me, and after the Galileo antenna I'd as soon not have to trust my faith in interplanetary origami. -------------------- Remember: Time Flies like the wind - but Fruit Flies like bananas!
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Aug 23 2005, 09:22 PM
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#4
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Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
4.5 billion is a lot. If I'm not wrong, this is 2 B$ 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] -------------------- I always think before posting! - Marco -
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