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Comment by pfdietz | Hacker News Reader

I'd be happier in a world where individual universities, or at least consortiums, could have their own space telescopes.

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The JWT is famous for costing over 10b USD to develop. AFAIK it's the most expensive object ever to be launched into space.

I don't think universities should (or could) spend that kind of money on research equipment.

If launch costs are 1% or less per mass of the Ariane 5, mass budgets could be greatly increased, and engineering could become easier. I see no reason ultimately why space telescopes should be much different in cost than terrestrial telescopes. Ultimately I see telescopes being maintained and upgraded in space much as terrestrial telescopes are.

The Webb telescope didn't go several times over budget from growing several times heavier. Novel telescope are expensive because they must address unique engineering challenges with unforeseen costs. You can't just grab a sunshade off the shelf – everything's built bespoke.

Of course, the flip side here is that it would be cheaper to build a second Webb telescope. Maybe we could mass produce a hundred more for a tenth the cost, but it's not clear that would be a hundred times better for astronomy.

That's not what I was implying. I'm implying the mass (and volume, and especially servicability) constraints required expensive engineering. Those constraints are relaxed with much cheaper launch, especially if in-space assembly and maintenance (by astronauts!) becomes affordable.

Its nice to be able to design things around Sci-Fi. However, still in 2022, there is no spacecraft that allows EVAs anywhere.

The occupants of the ISS beg to differ.

http://spaceref.com/iss/eva.html

I was unaware that the ISS was a spacecraft. I was under the impression it was a space station.

Im also unaware that the ISS is able to reach L2 or really any orbit other than LEO roughly 400km in altitude.

> I was unaware that the ISS was a spacecraft.

I can't really help that, but here is a nice page from NASA:

https://www.nasa.gov/audience/forstudents/5-8/features/nasa-...

"The International Space Station is a large spacecraft in orbit around Earth."

> Im also unaware that the ISS is able to reach L2 or really any orbit other than LEO roughly 400km in altitude.

You can tow it wherever you want, provided you attach a suitable propulsion device. That's also how it stays in that orbit, every now and then they boost it back up to offset the orbital decay.

Also: in space assembly could take place in orbit and then when the device is complete it can be sent off to L2. The problem with such a scheme is when things break down after the transit to L2.

Exactly the same kind of snark could have been uttered about lower cost launch before SpaceX upset the apple cart. It would not require enormous changes for something like Hubble servicing to be done with a Crew Dragon.

I hear what you are saying--if launches were easy they could have dropped a bunch of expensive constraints. But consider that if launch costs were truly the bottleneck for JWST, they'd have just thrown more money at the launch budget and got a bigger / fancier rocket. I'm no rocket science person but I'd assume you can scale launch capacity by throwing more money at it--it's generally a solved problem whose risks are much better understood than whatever JWST is doing. It makes sense to throw money at things to reduce risk like larger launch vehicles, regardless of their cost.

JWST is expensive because it does stuff that has never been done before. Lots of "unknown unknowns" that you need to make "known unknowns" Anything like this will be expensive--same is true for software even. You are working in uncharted water--risks are everywhere.

If they could have dropped a bunch of their constraints and reduced program risk by throwing money at a fancier launcher, they'd have done it. The fact they didn't suggests that the cost & risk wasn't constrained by the launch.

Now maybe you could argue that "if there was only a way to make it serviceable using cheap rockets"--then yeah maybe they could drop some of the more expensive and risky constraints. But however many years ago when this project started, such a thing was not even on the horizon. Only in the last few years has such a thing even begun to seem feasible. Perhaps future missions can relax their constraints because suddenly technology makes repair "easy". But JWST didn't emerge in that environment.

With lowered launch costs, and more things launched into orbit, surely over time you’d have to handle these unique engineering challenges yourself less and less.

Why can't universities launch space telescopes that don't cost as much as the most expensive one ever?

The ISS has cost a combined total of 150b$. It's apples and oranges, of course, but it can considered to be the single most expensive item ever built.

It's one of the most expensive objects period

Cubesats fill that role, for when those groups need their own. JWST is from the consortium of half the first world, because they want to measure the same thing. It’s not an either-or.

Johns Hopkins University is playing a fairly large role in the JWST mission

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