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Comment by HenryKissinger | Hacker News Reader

If the rocket explodes on the launch pad, it will be a bad day.

At the same time, it shouldn't take twenty years to build a space telescope, especially since it's not like it's the first one ever. The first atomic bomb was built in 4 years.

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It's not the first space-based observatory, but it's still a _wholly novel_ device, containing instrumentation designed by scientists and engineers in concert to leverage every piece of bleeding edge technology available at the time, and some throughout the process. Everyone of the flagship observatories is moon shot. It's not a mass-produced helicopter or missile. This project in particular is easily one of the wildest feats of science and engineering _ever_ just like Hubble, Cern, and LIGO.

Regarding the bomb, we were trying to end a global conflict, so the comparison couldn't be further off base.

Plus the bomb was built with the literal opposite purpose of the JWST: blowing up!

Worst case scenario it doesn't blow up exactly right and you just build another one?

I see your point, but you could also argue that worst case scenario for atomic bomb malfunction is much more awful than worst case for JWST

With the mindset at the time, the worst case scenario for the atomic bomb would have been it not going off in anyway way, and then they just handed their greatest enemy dud version if a top secret weapon.

Since it likely would have just blown up (fizzle) even if it didn’t fully detonate that is a pretty remote possibility.

Second worst would be it went off on a base somewhere and nuked a US base. Considering the location of these bases and the nature of the war at that point, it would have been a footnote causality wise, but embarrassing.

The worst case considered at the time was an uncontrolled chain-reaction annihilating the planet. It was calculated to be impossible, but it still weighed on the minds of many scientists involved, even well into the hydrogen bomb era.

https://www.insidescience.org/manhattan-project-legacy/atmos...

The first atomic bomb was nowhere near as precisely-built as the James Webb telescope has to be.

It is a completely novel design for a space telescope though. On top of that there's no capability [0] to go patch up a sloppy job like we did with Hubble.

[0] Currently at least. Starship could I guess but it was planned way ahead of Starship even being a glimmer in Musk's eye. Do they have any grapple points on it as insurance? I would at this point, just put one of the posts they use on the ISS for Canada Arm to grapple.

And that is the problem with 20 year (30 year?) product lifecycles. A lot can change in 20 years. For example the ability to service it might now be feasible. But since it’s almost entirely built, good luck making it serviceable!

There is a docking ring on the JWST.

Yeah, there is a docking ring as a "maybe we can design something to use this in the future". Since JWST is going out to a Lagrange point it would definitely be robotic servicing at this point unless our human spaceflight capabilities expand very significantly.

The Nancy Grace Roman (formerly WFIRST) space telescope also has grappling points for robotic servicing so it is something that is being considered in designs for programs of record.

It took 25 years to replace the SF Bay Bridge, a much less complex endeavor.

It’s simply how things are done around here these days.

That is not a good comparison. The SF Bay Bridge replacement project was conducted as a competition. The design that won was so much more complicated than all the other entries that at first it was not clear that it could be built and in fact the finished product is flawed with cracks and other failures. There is nothing particularly complex about the basic problem and the simple viaduct design that was advocated by the Governor at the time was expected to involve an order of magnitude less cost and time of construction but was rejected for being too simple and not beautiful enough. This management structure and these considerations have not been used for any space missions.

there has never been and never will be anything like the Apollo or Manhattan projects. They had levels of productivity that are not normally seen.

If the Starship program succeeds in reaching the moon in the next few years then I think that is comparable to Apollo. Ofc it is easier to do things the second time than the first but safety standards are higher and this time it will have been done at an enormously reduced price.

Well, there were the Egyptian Pyramids, Great Wall of China, Roman Aqueducts and a whole bunch of Great Projects in the past and I certainly hope there will be lots more in our future.

Those projects took centuries to complete.

As far as I know, the pyramids were each constructed for a single pharaoh, and during their single lifetime. I don't know about all of them, but that's at least true of Great Pyramid of Giza.

Or just a few turns, depending on your difficulty setting. (-;

We don't know how some of the Egyptian pyramids were constructed, or when, or how long it took.

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