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The James Webb Space Telescope has passed the final mission analysis review

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Re: The James Webb Space Telescope has passed the final mission analysis review

#81

Post by derekp7 »

jl6 wrote: post #54

If the JWST survives launch but has a subsequent mechanical problem that prevents it deploying properly (and it’s the kind of problem that would have been fixable on Hubble, using a shuttle mission) would it be feasible to mount a robotic rescue mission to chase it down and remote-hands it back to life? For less than the cost of just launching another JWST?

I would think that a cheaper (or multiple cheaper) versions could be made if they don't require the long lifespan and reliability that previous launch costs inflicted. Once Starship is going, and if it proves to be as low cost as the current projections, I could see multiple space telescopes being designed cheaply for a launch every year, each one designed in a narrow configuration that serves a specific purpose. But I really don't know what all goes into making a space telescope so expensive currently.

Re: The James Webb Space Telescope has passed the final mission analysis review

#82

Post by wolverine876 »

BitwiseFool wrote: post #60
jl6 wrote: post #54

If the JWST survives launch but has a subsequent mechanical problem that prevents it deploying properly (and it’s the kind of problem that would have been fixable on Hubble, using a shuttle mission) would it be feasible to mount a robotic rescue mission to chase it down and remote-hands it back to life? For less than the cost of just launching another JWST?

The JWST orbits out beyond the Moon, so I don't know if the Orion capsule and European Service Module even has the Delta-V to make it to that Lagrange point and back. Plus, I'm also unsure about the life support and duration requirements for such a mission. I imagine the only realistic repair mission would be with a Starship crew, seeing as Orion and all the other Commercial Crew vehicles would probably require some…

The GP asked about robotic, not human missions.

Re: The James Webb Space Telescope has passed the final mission analysis review

#84

Post by DubiousPusher »

systemvoltage wrote: post #72
DubiousPusher wrote: post #65

Earlier quoted context omitted.

By that logic, so is the military, public schools and highway maintenance.

Any over budget and poorly run government program I see it as a jobs program. F-35, CalTrain, NASA SLS, etc. This is in stark contrast with partnerships with private industries. For eg DARPA + Moderna or NASA + SpaceX.

I fail to see the difference. Private contracts often go over budget. The F-35 itself is full of privately contracted parts. Many public/private partnerships contracts are even no bid, meaning they are essentially uncompetitive. Whether the government hires people directly to do a job or whether they contract it out is equally distortionary. By allocating tax dollars to a public rocket lab or to a private rocket company you are increasing the demand for rocket engineers and thus creating a "rocket engineer" jobs program.

Re: The James Webb Space Telescope has passed the final mission analysis review

#85

Post by wolverine876 »

cromwellian wrote: post #83

I feel like this is an all-eggs-in-one-basket mission. If it fails to launch, we have nothing. Why not build many JWSTs, surely the cost per unit would go down, and launch more than one?

> surely the cost per unit would go down, and launch more than one?

Surely? They didn't build a JWST factory. It might go up, as people with specialized skills or knowledge have moved on.

Re: The James Webb Space Telescope has passed the final mission analysis review

#86

Post by wolverine876 »

tomschlick wrote: post #11
tectonic wrote: post #3

Such an exciting, and high stakes, and dramatically late and over-budget mission.

Government red tape and contracting at its finest Edit: Downvotes with no comments as to why... This thing is 24 years in development and 20x over budget. If thats not a failure of government contracting, budgeting, etc then idk what is: https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Cos... - Obviously the platform will be cool once they get it launched, but until then its just a money pit.

What basis do you have for blaming government contracting? Lots of projects built by lots of organizations are very late and over-budget. One difference between government and private industry is that the government has the resources and motivation to persist - they aren't in it for profit. If this was a private company, it may have been canceled long ago as unprofitable. Is that a preferable outcome?

In fact, wasn't the JWST built by Northrop Grumman to a great extent? Why not blame them?

EDIT: It's hard to criticize government contracting in the same context as NASA, which has taken more risks and achieved new things far beyond any private organization in history. NASA has operations throughout the Solar System, and in interstellar space. They are the only organization to put humans on the moon - 50 years ago! Can anyone else say anything that? SpaceX?

Re: The James Webb Space Telescope has passed the final mission analysis review

#87

Post by ufmace »

jl6 wrote: post #54

If the JWST survives launch but has a subsequent mechanical problem that prevents it deploying properly (and it’s the kind of problem that would have been fixable on Hubble, using a shuttle mission) would it be feasible to mount a robotic rescue mission to chase it down and remote-hands it back to life? For less than the cost of just launching another JWST?

The trouble with robotic repair missions is that it could work pretty well if you knew 100% exactly what was wrong, and exactly what else might go wrong while applying the fix for whatever went wrong. The more potential unknowns, the harder it is. It's much harder to make a robot with enough general flexibility that it could probably handle diagnosing and repairing an unknown issue, or handle something going wrong while trying to carry out a planned repair sequence. Bolts jammed, too loose, too tight, tanks of stuff springing leaks, electrical short in some unknown place, component overheating for unknown reason, all sorts of things can go wrong that are tough to diagnose remotely or with a special-purpose robot.

Re: The James Webb Space Telescope has passed the final mission analysis review

#88

Post by DubiousPusher »

perihelions wrote: post #77
DubiousPusher wrote: post #63

Earlier quoted context omitted.

It's because this is a flippant, unhelpful attitude. If we were talking about building a mile of blacktop highway then such a casual observation about the overrun might be warranted. But we're not talking about that. We're talking about building the first non-orbital space telescope in human history. To a certain extent, no one could know the actual cost ahead of time. It's one of those things you kind of have to do…

"the first non-orbital space telescope" There've been a few others, including Gaia (SEL-2 halo orbit -- same as JWST), and Kepler (heliocentric). [edit]: also Herschel (SEL-2) https://en.wikipedia.org/wiki/Gaia_(spacecraft)#Launch_and_o... https://en.wikipedia.org/wiki/Kepler_space_telescope#Orbit_a... https://en.wikipedia.org/wiki/Herschel_Space_Observatory#Lau...

Interesting. I assumed these were in orbit like other satellites. I didn't realize they operated from the Lagrange points. Thanks.

Re: The James Webb Space Telescope has passed the final mission analysis review

#89

Post by wolverine876 »

systemvoltage wrote: post #72
DubiousPusher wrote: post #65

Earlier quoted context omitted.

By that logic, so is the military, public schools and highway maintenance.

Any over budget and poorly run government program I see it as a jobs program. F-35, CalTrain, NASA SLS, etc. This is in stark contrast with partnerships with private industries. For eg DARPA + Moderna or NASA + SpaceX.

All those projects were built by private industry, including the latter two.

Re: The James Webb Space Telescope has passed the final mission analysis review

#90

Post by bronson »

bpodgursky wrote: post #43
baggy_trough wrote: post #2

Going to be amazing if this thing can actually unfurl, but I'm scared.

I almost want the unfurling to get stuck, just b/c SpaceX launching a manned Starship out to a LaGrange point to hotfix it would be super cool.

Fly out there, spacewalk over, give it a little jiggle, looks good, fly home.

It would be like driving six hours to push a power button, but epic.

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