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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

#121

Post by bumby »

phkahler wrote: post #113
derekp7 wrote: post #81

Earlier quoted context omitted.

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…

>> But I really don't know what all goes into making a space telescope so expensive currently. I think you already said it. The long life (high reliability) requirement, and I'll add the complexity of having it unfold. Both of those become non-issues if you build the telescope right into a space-X starship. There may be other issues with that, but the mirror wouldn't need to fold ;-)

Are you speaking to the reliability of the launch vehicle or of the satellite? The launch itself is typically not a primary cost driver of a satellite mission. Complexity may be, due to constraints of the fairings but the manufacturing and quality checks drive quite a bit of the cost

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

#122

Post by abz10 »

bumby wrote: post #120
mtdewcmu wrote: post #118

Earlier quoted context omitted.

Unlike the F-35, I think the taxpayers are getting their money's worth.

Unfortunately, I think it's easier to fund something like the F-35 because it can be framed as a way to avoid an existential threat. It's difficult to do the same with fundamental science

The F-35 was framed as a way to save money.

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

#123

Post by meepmorp »

CamperBob2 wrote: post #59
cnlevy wrote: post #46

Earlier quoted context omitted.

Using 3 COTS (Commercial Off The Shelf) components with 90% reliability can ensure 99.9% redundancy instead of having a Unique very reliable and even costlier 99.9% custom component can really lower costs. But it can happen only if mass is not a constraint. From Casey Handmer's blog: https://caseyhandmer.wordpress.com/2021/03/04/sls-what-now/ The Perseverance Mars rover cost $2.4 billion, which works out to a few tho…

They should put that team to work on next-generation tech, the stuff that's not yet a commodity. They can start working on habitat construction materials and hardware, for instance. Although it is interesting to consider that we've put a lot of expense into optimizing payloads that, in retrospect, would have been smarter to put into better launch vehicles. SpaceX probably isn't going to spend $2 billion developing St…

IIRC, SpaceX is getting $2.89B from NASA for the Artemis lander, which proposal is based on Starship. Although, the GAO put that on hold recently, after complaints from BlueOrigin and Dynetics. Hardly surprising, I guess.

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

#124

Post by sawjet »

mtdewcmu wrote: post #118
keanebean86 wrote: post #76

Earlier quoted context omitted.

$9.5 billion over is pocket change! If you adjust for inflation $10 billion is only $7.7 billion in 2007 dollars. Assuming the telescope works I can live with it being expensive.

Unlike the F-35, I think the taxpayers are getting their money's worth.

All those European tax payers are certainly getting their money's worth

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

#126

Post by nhoughto »

ufmace wrote: post #87
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 wh…

And you’d need to have it designed to be serviceable once deployed. I’d imagine there would be a few assumptions going into the design process, “once deployed humans won’t ever need to get to that..”

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

#127

Post by bumby »

abz10 wrote: post #122
bumby wrote: post #120

Earlier quoted context omitted.

Unfortunately, I think it's easier to fund something like the F-35 because it can be framed as a way to avoid an existential threat. It's difficult to do the same with fundamental science

The F-35 was framed as a way to save money.

That argument only holds because it was purported to replace different weapons systems that were needed for mitigating a threat. The threat is the primary motivation and cost reduction is secondary. I.e., if not but for the existential threat there's no need for the JSF or any system it would replace.

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

#128

Post by pklausler »

phkahler wrote: post #116
pklausler wrote: post #99

Earlier quoted context omitted.

It's not an orbit, per se, but... it will go around the Earth once per year.

>> it will go around the Earth once per year. I think more accurately it will go around the sun once per year. The earth will provide the extra gravitational pull (toward the sun) needed to orbit the sun at a larger radius than the earth in the same amount of time as the earth.

Sure, but it also goes around the Earth once per year, too, sidereally.

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

#129

Post by e_y_ »

bl5THJUSFXWy4ii wrote: post #95
mcbutterbunz wrote: post #78

Earlier quoted context omitted.

> I'd peg that mission at $300 - $500 million. If that was the cost for that mission, it would be worth it considering JWST cost about 20x that amount.

You are considering the entire cost of developing the JWST. Surely the cost of building another based on the finished design would be lower.

I think part of the reason the JWST took so long to build was the complexity of the design. As in, it was difficult to manufacture and assemble and test due to the way it was designed. It might be cheaper to do it a second time based on the lessons (avoiding mistakes) from the first, but it would probably still be quite expensive.

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

#130

Post by SiempreViernes »

mongol wrote: post #53

What is it hoped this can see? Is there some specific hypothesis this telescope was built to confirm?

Hopefully it'll tell us about the period of reionisation, when the light of the first galaxies made the universe transparent again.
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