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The James Webb Space Telescope (JWST) project could be fantastic, It has the promise of seeing farther than Hubble, almost to the beginning of our space/time.

But, orbiting at L2 - while closer by far than other LaGrange points - is still 1.5m KM away from Earth. That is four times more distant than humans have ever travelled.

My question is this: This project has had a difficult construction history. (Most do but this has been more challenging). Are there ideas or plans for rescue/repair/restore missions if/when something goes wrong?

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ICL1901
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    You are swearing in church! JWST, the major space telescope project of our quarter of a century will succeed and will be a triumph. If there's an issue then entrepreneurial and astronautic supermen will emerge and somehow simply improvise a fix. Docking Dragon with Bigalow and something else and just go there and make things good. When everything is at stake on one single mission, nerves and politics are at play and the tendency is to postpone the potential fiasco to keep the dream alive. But honestly, the failure ratio is getting very low even for more challenging missions like Mars landings. – LocalFluff Jun 30 '14 at 14:49
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    I like your attitude! – ICL1901 Jun 30 '14 at 15:06
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    Not worthy of an answer, but note that the JWST will "break" about ten years after launch. That's when it runs out of fuel. – David Hammen Jun 30 '14 at 21:09
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    It is imho, worthy of an answer.. But anyway, can the fuel cells be replaced? It's taken a long time to build the JWST, and wouldn't we have to start on its replacement now to be ready in 10 years? – ICL1901 Jul 03 '14 at 11:54
  • Interesting question! This is slightly related: http://aviationweek.com/new-space/no-second-chances-webb-telescope-deployment – uhoh Nov 09 '16 at 10:03

3 Answers3

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There is a docking ring on the JWST, so in theory astronauts could visit it. It would be easier to get to JWST than to the Moon, but more difficult than LEO like we have been doing. Edward Weiler, director of NASA Goddard Space Flight Center, had this to say on the subject:

We cannot make the James Webb Space Telescope fully serviceable like the Hubble because that would cost so much money that I don't think this country could afford it. However, what if you have a bad day when you put this thing a million miles out and everything folds out except for an antenna ... it gets stuck? Or a solar panel doesn't fold out completely, and you say, 'gee, I wish we could send an astronaut just to give it a kick'?

PearsonArtPhoto
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  • Your source is 7 years old. Is the docking capability still in the mission? – LocalFluff Jun 30 '14 at 14:40
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    I can't find anything to suggest that it's not. Still, there doesn't seem to be much about this in the last several years... – PearsonArtPhoto Jun 30 '14 at 14:45
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    "that would cost so much money that I don't think this country could afford it" I find that hard to believe. We spent just under $1 billion a day in Iraq for years; we could no doubt "afford" to do whatever we wanted with JWST. The question is not whether we can afford to, but whether we want to. – TylerH Feb 01 '18 at 20:17
  • James Webb Space Telescope Program Scientist Dr. Eric Smith spoke about this on TMRO recently and mentioned that there were optical targets near the fuel ports that could potentially be used for refueling. – Head Pancakes Apr 15 '19 at 03:41
  • @HeadPancakes optical targets potentially used for docking perhaps? – uhoh Dec 29 '21 at 03:01
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As of 2013, NASA still had a docking ring for the JWST. ① While they have no plans to service JWST, they left the docking capability just in case.

The most likely service vehicles are either an Orion capsule (4 man) or Dragon 2 Capsule (7 man); a Dragon 2 atop a Falcon Heavy could easily reach and have delta-V sufficient for return. ②

References

① Space.com JWST Infographic (http://www.space.com/21232-nasa-james-webb-space-telescope-infographic.html)

② SpaceX Dragon 2 (http://www.spacex.com/news/2014/05/30/dragon-v2-spacexs-next-generation-manned-spacecraft)

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aramis
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    Great. Thanks.. +1 Any idea when those vehicles will come online? (and how did you make your 1 and 2 circles/numbers :) – ICL1901 Jul 03 '14 at 11:52
  • Is there a published mass breakdown for the Dragon 2? – MercuryPlus Jul 03 '14 at 14:22
  • The circled numbers are standard unicode (U+2460 to U+2469), @DavidDelMonte. – aramis Jul 03 '14 at 17:36
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    @MercuryPlus a total mass has been mentioned in videos by Elon Musk. He's mentioned previously that the design is intended as a shuttle capability replacement. – aramis Jul 03 '14 at 17:38
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None whatsoever. If JWST has issues, it is basically out of luck.

Maybe one day, Orion might be able to go visit, but Orion is a lousy repair platform compared to the Shuttle.

Shuttle had more crew (7 vs 4), more room for equipment, a place to dock the Hubble as a work platform, an RMS to move heavy equipment around (in and out of the Hubble).

geoffc
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    Thanks for the answer, although I was hoping for something more optimistic.. This is what I feared.. Well. I hope all the low bidders got their pieces right. – ICL1901 Jun 30 '14 at 11:52
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    I like the idea that private industry would mount an effort to fix and takeover the spacecraft/telescope.. – ICL1901 Jun 30 '14 at 15:20
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    @David DelMonte "Takeover", yeah, I can see how Elon Musk's South African grandfather Auric Goldfinger and his cat will defrost back to life and space pirate the JWST in a Dragon capsule to hold the world astronomical society ransom for... a million dollar! – LocalFluff Jun 30 '14 at 16:00
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    You know I meant takeover in the sense of engineering project management, and not in the sense of ship piracy... – ICL1901 Jun 30 '14 at 16:10
  • JWST will be at least 15 years in space before the SLS will be able to get astronauts out there to fix it. As noted, there are no provisions for fixing anything on it beyond whacking it with a hammer. I suspect that was deliberate as it will justify the expense of another, 'bigger and better' telescope. If they were really serious about this project being long-term - like Hale 200-inch at Mt. Palomar now 75 years and STILL working - they would have put this puppy on the Moon. Or, better, Mercury. – MercuryPlus Jun 30 '14 at 17:29
  • @MercuryPlus As noted by PearsonArtPhoto, it will be easier to get to JWST's selected orbital position than the Moon. And much easier than Mercury. The Moon is in a gravity well, and on top of Mercury also being in a gravity well it is in a different orbital plane around the Sun and further away. I believe your pro-settlement bias is clouding your judgment here. – called2voyage Jun 30 '14 at 18:48
  • @called2voyage. Understood. Still, delta-V is just one parameter used to determine a mission's cost. Cost always has to be measured against gain. It is short sighted to say let's save the money on delta-V and doom this telescope to , maybe, 25 years useful life when putting it on the Moon makes it permanently available to base (established for a variety of missions) for anyy decades to come. – MercuryPlus Jun 30 '14 at 18:58
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    @MercuryPlus The Moon rotates. Albeit tidally locked with Earth, that puts nearly any location on it with exception of a few crater rim peaks at its North pole in the shadow for half of its orbital period (so nearly 328 hours). That means a lot of problems providing power for solar powered JWST, thermal cycling, need to relay comms, and complicate targeting its objects of study. Moon's surface isn't exactly a static environment. In SEL2 halo orbit, you get sunlight all the time, and ample time to precisely point with reaction wheels at large part of the skies as Earth rotates around the Sun. – TildalWave Jul 01 '14 at 01:44
  • All of the reasons you mention are why you want the telescope integrated into a Lunar Base operation. The base has the same problems to resolve and can readily incorporate power, thermal and comm. management. Plus maintain and upgrade. As for thermal cycling, I agree the Moon is too stressful. Now, if the telescope were on Mercury, you would have six times as long (88 days vs 14) to view a specific object, even if you are using cryo-cooled sensors. Pointing and tracking are simpler too. As for the delta-V, for a telescope likely to be useful for 100 years, I'm ok with the cost. – MercuryPlus Jul 01 '14 at 03:27
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    @MercuryPlus What Lunar Base operation? I wish I could tell you otherwise, but we don't have any. – TildalWave Jul 01 '14 at 14:32
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    @TidalWave: That's right. We don't have a Lunar Base. Why? My pet theory is that, had NASA combined its astronomy/physics/planetary programs with a Lunar Base program, we would have a Lunar Base doing valuable work in all these fields plus other interesting tasks (satellite retrieval, asteroid defense etc.) all while developing an infrastructure to get humans to Mars economically. So again, why no Lunar Base? Because dissertations on gravity waves are nowhere near as fascinating to the general public than watching a cute little go-cart trundle around on Mars, so NASA says its Mars. – MercuryPlus Jul 01 '14 at 15:12
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    @MercuryPlus I'd argue it's more likely STS costs stopped manned exploration outside of LEO. I think this discussion merits being taken to chat. – Ezra Bailey Jun 26 '15 at 18:23