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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

#211

Post by spaetzleesser »

jasonwatkinspdx wrote: post #178
7373737373 wrote: post #160

Earlier quoted context omitted.

I wonder the same for large (especially international) companies, government bureaucracies or other organizations. With thousands of employees and branches in different locations, it must be impossible to get a full understanding of the state of the system.

This is what Systems Engineers do. There's no magic bullet, but the basic process is lots and lots of documents. Much of what NASA does is published openly so you can get a feel for what some of these document types are like. The wiki page gives a decent summary. Building a model for the system is indeed a big part of the challenge. These days it's increasingly done as a fully detailed software simulation. The big CA…

“ There's no magic bullet, but the basic process is lots and lots of documents.”

That’s probably it. My company has systems engineers and even in relatively small projects you often have inconsistent and incomplete requirements. It’s one thing to design a piece of hardware but you also need to track how logistics and other factors have an impact on the system. So you need a lot of people who constantly check these changes.

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

#212

Post by spaetzleesser »

sydthrowaway wrote: post #200
jasonwatkinspdx wrote: post #178

Earlier quoted context omitted.

This is what Systems Engineers do. There's no magic bullet, but the basic process is lots and lots of documents. Much of what NASA does is published openly so you can get a feel for what some of these document types are like. The wiki page gives a decent summary. Building a model for the system is indeed a big part of the challenge. These days it's increasingly done as a fully detailed software simulation. The big CA…

Ugh, I can't deal with Systems Engineering. It's a whole lot of gobbledygook before getting to the crux of the problem. A software engineering analogue would be FizzBuzz Enterprise Edition https://github.com/EnterpriseQualityCoding/FizzBuzzEnterpris...

I don’t like it either but in regulated industries like space, medical or aerospace it seems the only way to manage things in a controlled way.

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

#213

Post by techdragon »

bane wrote: post #191

It's my personal belief that these massive R&D space telescope programs are nearing their end. Computational approaches among multiple sensors, combined with good 'ol factory mass manufacturing powered by low-cost reusable launch technology allows for the money spent on one-shot programs like this to be spent and allocated in radical different ways. Instead of building one huge short life-span spacecraft, why not lau…

I'm building this! Minus the "computational methods" magic... Because as someone has already commented, there are significant issues with just merging the telescope data together with computational magic.

With the advent of SpaceX's Starship providing a 100% (and the 100% is crucial to the economics of this project) reusability there is significant potential to reduce many of the costs that normally increase the price of a satellite. From not throwing away a $10,000 PPOD (cubesat deployer) to the myriad cost savings available when you know the next flight is cheap and you don't need to buy a $500 part, where a $50 or even $5 part would do the job, due to the different risk profile in many smaller satellites, compared to a few larger ones.

> Instead of building one huge short life-span spacecraft, why not launch hundreds or thousands of lower cost, less capable birds incrementally? You can start with a small "first light" capable instrument with a dozen or so spacecraft, then over time and more launches put up more and more capability and decommission failed or low capability pieces.

Thats the basic plan in a nutshell. Start small, build up, from the ~10cm primary mirror "phase one" prototypes, to eventually using ~50cm primary mirrors. Steady progress using a standardised telescope "chassis" for each generation, with each having a specific camera/instrument rather than the common (for space telescopes) practice of having complicated multi-instrument optical pathways.

Think Planet Labs, but facing out at the universe, not down towards the ground, and a non-profit/charity not a commercial company.

I'll spare the whole spiel that I've regurgitated into grant proposals (space costs money and it would be nice if I didn't have to pay the entire $250,000 or more out of my own pay-check over the course of a decade) if you want to know more (or just talk about it, or offer to help, or whatever else at all) you can contact me directly (email in my HN profile) or wait till I publish the eventual website later this year, I'll be sure to post a Show HN once I have pretty pictures of hardware.

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

#214

Post by imglorp »

nine_k wrote: post #203
bane wrote: post #191

It's my personal belief that these massive R&D space telescope programs are nearing their end. Computational approaches among multiple sensors, combined with good 'ol factory mass manufacturing powered by low-cost reusable launch technology allows for the money spent on one-shot programs like this to be spent and allocated in radical different ways. Instead of building one huge short life-span spacecraft, why not lau…

As already said, the problem is in coordination of multiple telescopes in spacetime. It might be better to build one giant telescope piecemeal, by adding more and more small mirrors. A similar approach is taken by several terrestrial telescopes. It would still be very interesting to have a few space telescopes distributed across the Solar system, much wider than the Earth orbit. It could give a sort of stereoscopic p…

Actually, pulsars can be used for timing and position, and all telescopes in your fleet could have sight of the same ones. It's probably far easier to do interferometry if you don't have atmospheric distortion to deal with.

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

#215

Post by caconym_ »

minikites wrote: post #70
endymi0n wrote: post #69

While it‘s awesome to finally see the JWST finally come to close to launch after all those years, now it‘s a close race between it and SpaceX Starship that could have taken the 6.5 meter mirror up to space in one whole piece in its 9m diameter belly rather than having to do all the miraculous origami that took two decades to develop in the first place…

I wouldn't trust any payload on a SpaceX ship given their track record.

Falcon 9 (and Heavy) has not experienced any kind of mission failure since 2016, the latter period accounting for (if I'm counting right) 69% of its total launches including the Amos-6 pad failure (which did not actually launch). Its actual failure rate is 1.5%.

It's not a track record that deserves any more derision than its contemporaries. Doing so in such vague terms just makes you look like you don't know what you're talking about, which goes double if you're thinking not of F9, but rather of those big shiny rockets they've been blowing up in Boca Chica recently. That (Starship) is a development program.

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

#216

Post by frakkingcylons »

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.

Your comment doesn't add anything to the conversation. But for anyone else that is actually interested: the cost of JWST is really not that extravagant considering how much more capability it provides compared to HST.

> Not even including its four space-shuttle servicing missions, Hubble cost $4 billion or $5 billion in today's dollars just to build and launch," Dressler notes. "Here we are, building a telescope that is almost seven times bigger, it is cryogenic, it is operating 1.5 million kilometres away, and it is costing the same amount as Hubble did, if not less. That is remarkable, and this is probably the biggest scale on which we will consider building such things in this country."

From this article: https://www.nature.com/articles/4671028a

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

#217

Post by caconym_ »

jasonwatkinspdx wrote: post #103
endymi0n wrote: post #69

While it‘s awesome to finally see the JWST finally come to close to launch after all those years, now it‘s a close race between it and SpaceX Starship that could have taken the 6.5 meter mirror up to space in one whole piece in its 9m diameter belly rather than having to do all the miraculous origami that took two decades to develop in the first place…

While I'm rooting for SpaceX with Starship, lets be clear: they're still trying to get hovering grain silo versions working. Meanwhile JWT is ready to go. If it's a race one side has already won rather emphatically.

Actually, they're well beyond the "grain silos" by now. They've successfully demonstrated the "bellyflop" landing maneuver from a terminal velocity fall, and now they're (credibly) trying to launch a full prototype Starship stack to orbit within the next few months.

Wiki says JWST is planned to launch by this November, so I think there is a decent chance Starship beats it into space. That won't be a production-ready vehicle, and launching anything valuable on it (let alone something like the JWST) would be certifiable, but let's give credit where it's due.

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

#218

Post by wolverine876 »

gpt5 wrote: post #208
bane wrote: post #191

It's my personal belief that these massive R&D space telescope programs are nearing their end. Computational approaches among multiple sensors, combined with good 'ol factory mass manufacturing powered by low-cost reusable launch technology allows for the money spent on one-shot programs like this to be spent and allocated in radical different ways. Instead of building one huge short life-span spacecraft, why not lau…

Even if this computational photography vision is years away, JWST might still become obsolete quickly. SpaceX's Starship would be able carry telescopes than JWST as a single piece. This would dramatically simplify development and increase optical quality.

Could you back that up with anything? There is so much excitement about SpaceX, it seems like all I read about on HN.

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

#219

Post by nullifidian »

gpt5 wrote: post #208
bane wrote: post #191

It's my personal belief that these massive R&D space telescope programs are nearing their end. Computational approaches among multiple sensors, combined with good 'ol factory mass manufacturing powered by low-cost reusable launch technology allows for the money spent on one-shot programs like this to be spent and allocated in radical different ways. Instead of building one huge short life-span spacecraft, why not lau…

Even if this computational photography vision is years away, JWST might still become obsolete quickly. SpaceX's Starship would be able carry telescopes than JWST as a single piece. This would dramatically simplify development and increase optical quality.

https://www.youtube.com/watch?v=kEECPKLHwl8 https://en.wikipedia.org/wiki/Large_strategic_science_missio...

They are already planning telescopes using Starship's capabilities, and one of these telescopes has a mirror that consists of several segments, albeit not hexagonal and is pre-assembled. The telescope is being touted as an overall cheaper solution due to the diameter that Starship could carry. But there is also a telescope that is an enlarged version of JSWT.

JWST is probably a required stepping stone for these future telescopes.

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

#220

Post by wolverine876 »

abhiminator wrote: post #52

On a related note, I highly, highly recommend watching this well-made documentary on JWST, released around 3 and a half years ago -- https://www.youtube.com/watch?v=FLD9LKq0u9E This documentary was produced by Northrop Grumman Corporation -- the builders of JWST under a NASA contract.

> This documentary was produced by Northrop Grumman Corporation -- the builders of JWST under a NASA contract.

Is it promotional material?

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