I think the James Webb Space Telescope is going to be positioned beyond the moon. Which would bring into question: Can it be serviced, or is it going to be a one shot deal?

ToSeek can tell you more certainly, but I think it is being designed to support robotic servicing.

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As far as I know the JWST is going to be over a million kilometres away from Earth. There is currently no manned spacecraft capable of going there and servicing it. The Orion craft from the Constellation program could get there with an Ares I and Ares V, but at the moment it's being debated whether these will even be built, so who knows.

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I doubt that it is intended to be serviceable robotically, since that would
depend on robotic capabilities not yet possible. The time delay makes
remote manipulation extremely difficult. Twenty years ago I attended a
colloquium in which planetary scientist G. Jeffrey Taylor advocated manned
bases on the Moon to operate robotic lunar exploration devices remotely,
because the time lag from Earth is too long. Robotics which could do the
job semi-autonomously is certainly conceivable, but since the technolgy is
not yet in hand, it can't be counted on, and would be difficult for engineers
who aren't clairvoyant to design JWST for.

-- Jeff, in Minneapolis

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"I find astronomy very interesting, but I wouldn't if I thought we
were just going to sit here and look." -- "Van Rijn"

"The other planets? Well, they just happen to be there, but the
point of rockets is to explore them!" -- Kai Yeves

JWST is not intended to be serviced at all. It's all or nothing. Kind of like Cassini (which was of similar engineering magnitude).

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NASA JWST FAQ:

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when you get right down to it, it's just a really big, really expensive disposable camera.

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The.. Best.. Thread..Ever...

NASA: NASA Pondering a Future Grapple on the James Webb Space Telescope (2007 May 31)

Anyone know the results?

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That pretty much covers anything that's been launched for exploration. There are a (very) few exceptions (like HST).

Fred

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No - as others have pointed out, it is not designed to be serviced at all. It'll either work or it won't.

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Well...

I don't think I'd have to say how wonderful HST was.

So cheers to hoping to JWST and the future!

was/is......

Has been, has beer!

-- Jeff, in Minneapolis

__________________
http://www.FreeMars.org/jeff/

"I find astronomy very interesting, but I wouldn't if I thought we
were just going to sit here and look." -- "Van Rijn"

"The other planets? Well, they just happen to be there, but the
point of rockets is to explore them!" -- Kai Yeves

The Ares V type telescope would feature a monolithic mirror and a docking port in back according to one paper I've seen. Webb's a harder fix I should think.

You think wrong again. Webb would be easier to fix since it is not monolithic

Chandra was planned for servicing early in its construction, before its location was changed to an unreachably high Earth orbit. That's one reason that its grazing-incidence mirrors deliver better images than can be properly sampled by any of its detectors; the original spec allowed for upgrades in orbit, and the lead time for the mirrors meant they were pretty much finished by the time servicing was out of the question.

I suppose you'd have to consider the price of a maintenance mission versus the cost of building and launching a new telescope. I suspect it would be a big saving to send something with a robotic arm up there and fix it.

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Or, they just build it right the first time. Like Cassini.

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"What do you care what other people think?" -- Richard Feynman
"For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." -- Feynman, at the conclusion of his Challenger report

It doesn't have a docking port to allow interior access either, as some of the drawings of the simpler monolithic scope explain. More to a scope than just mirrors. But you're bigoted against anyone at MSFC of course.

Augustine: Moon Return a No-Go. . . .

Augustine: Moon Return a No-Go. . . .