Comment by uoaei | Hacker News Reader

Comment by uoaei | Hacker News Reader

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Have you done any research into the budgeting process?

Edit: I googled it. Here's the first paragraph of the first link from DDG:

> The James Webb Space Telescope (JWST) is expected to cost NASA $9.7 billion over 24 years. Of that amount, $8.8 billion was spent on spacecraft development between 2003 and 2021; $861 million is planned to support five years of operations. Adjusted for inflation to 2020 dollars, the lifetime cost to NASA will be approximately $10.8 billion.

So "spacecraft development" comprised about 90% of the total budget. Of the remainder, 96% is allocated to "five years of operations". So we have about $39 million left over, which I assume covers the launch and everything around it. If you want to try optimizing that, go ahead, but it is nearly a rounding error (0.4% of budget) in the grand scheme of things.

There is an argument to be made that a few million dollars saved is valuable. I would propose a counterargument, that the amount of friction induced by working with private contractors (especially contentious and manipulative ones like those who run SpaceX) would add to some of the development costs, so the savings may not be as big as you think from a naive comparison.

Part of the huge cost to develop it was getting a mechanism that could deploy the mirror segments into a large enough array with sufficient accuracy, a task that would be dramatically simplified by a a launch platform with a wider fairing and greater mass to the L2 Lagrange point. So yes, if SpaceX Starship was available, it would've saved a ton of money on JWST, albeit mostly by relaxing the design parameters of the telescope rather than through cheaper launch costs.

An engineering way to deal with inaccuracy is to make things adjustable with feedback.

It's like the silly analogy I hear now and then that sending a probe into the solar system is like throwing a baseball from LA to NYC and hitting a small target there. It isn't like that at all. The probes undergo course corrections as necessary.

> if SpaceX Starship was available, it would've saved a ton of money on JWST

How much? How much did it cost for the actual JWST? Do you have any evidence of this great cost?

The glorification of Musk's ego is endless. Can JWST see the farthest reaches of it? Is it expanding or contracting?

It's pretty trivial to tell that a large portion of JWST's delays were related to the unfolding mechanism (first building it, then the 5 years of delays from a ripped sunshield, loose screws and more), much of which would be rendered unnecessary by Starship's wider payload bay. Thus of course it would've saved a ton of money on the telescope. The telescope wouldn't have needed so much testing if it didn't have 344 single points of failure, and it wouldn't have that many of those if it didn't need its unfolding mechanism.

If that isn't convincing enough, the budget plan including all folding mechanisms etc before testing was $6.5B, so the $3.5B extra was spent entirely on testing and repairs. Thus, if a folding mechanism was not needed, they could have saved at least that much on testing and fixing said mechanism.

Might be a good idea to take off your blinders before complaining about someone being more successful than you. Since your jealousy is blinding you so much, it would have been just as convenient for costs if any other rocket had a wider payload fairing than Ariane 5.

This has nothing to do with Musk. A larger payload fairing diameter means fewer/no elements of the mirror have to be folded up for launch, means reducing or completely avoiding the multi-hundred step deployment procedure, the design of which was both an enormous engineering undertaking and most of the over 300 single-points-of-failure[0] in the final design. It doesn't have to be the SpaceX Starship, but there's no other launch vehicle currently in development with a comparable payload diameter. Since it's a purely hypothetical as the entire design process took place with launching on Ariane 5 in mind, I have no idea what the cost savings would be, but it is self-evident they would be considerable. The thing isn't made of $8B worth of metal, the cost was in engineering it.

[0] https://www.space.com/james-webb-space-telescope-deployment-...

> it is self-evident

Nope! It doesn't cost 8 billion to unfold a mirror. Seems like a rather straightforward mechanical problem to me. And your baseless theories and mine are worth nothing without evidence. That's the reason we built the JWST - we need evidence. Baseless nonsense is the stuff of cults of personality, not knowledge. We need much more of the latter and much less (i.e., none) of the former in our society.

Okay, engineering time costs money. Absolutely staggering amounts of engineering time were spent ensuring that the extremely intricate, highly prone-to-failure deployment process would be successful. With a larger payload diameter, the mirror deployment process could have been dramatically simplified, thus saving some percentage of the staggering amounts of engineering time expended, thus saving some percentage of the billions of dollars spent to get the telescope to the launchpad. I do not care what company produces the launcher with the bigger payload diameter, OP specifically asked about Starship, and the answer is YES, a launcher with a significantly larger payload diameter than what is currently available, like Starship if it is ever successful, would make an undertaking like the JWST easier to design, and thus cheaper to design. I dislike Musk as much as any disinterested party (I'm sure people he's scammed with his "FSD next year" or people he's sexually harassed, and definitely his children dislike him more), but a better launch vehicle WILL make bleeding-edge space missions cheaper, and better. That is wholly unrelated to one obnoxious egomaniac.

I think OP is saying they would have had the space to simply built one large mirror instead of many different mirror segments that require complicated motors and moving parts to deploy into position.

The mirror segment deployment technology is surely a significant percentage of the cost.

> surely

Is there a more common or obvious trap of reasoning? If 'surely' worked, we wouldn't have needed the Enlightenment, science, or the JWST to learn about the universe.

IIRC (much stronger evidence than 'surely', but still lacking), it's in fact not significant to the cost.

>IIRC

Is there a more common or obvious trap of reasoning? If 'IIRC' worked, we wouldn't have needed the Enlightenment, science, or the JWST to learn about the universe.

And if SpaceX was available with a larger payload, engineers would have built the same folding telescope, only much larger and more costly.

Basically, it's the cost of designing and building a complete one-off that's going to be launched off into space, deployed, no opportunity to repair, etc. There are a million things that can go wrong. And you have one shot.

I know someone who was one of the test engineers on SDO (solar dynamics observatory) and there were all manner of concerns about this, that, and the other thing that were really hard to say were almost absolutely certainly "just fine."

> Basically, it's the cost of designing and building a complete one-off […]

As a simple analogy: there's a difference between going to 3-for-1 Suite Warehouse and going to Saville Row and getting something bespoke.

It's just there are no COTS satellites that do what JWST do, so if you want to do cutting edge science you're paying for Saville Row.

Probably even worse than that. They're effectively often designing special fabrics, threads, and tools to do the sewing. Not that I have a need any longer, but custom suits in lower cost of labor areas aren't a big deal and even off-the-rack suits pretty much have to be tailored for many of us to look good.

First rule in government spending: why build one when you can have two at twice the price?

> especially contentious and manipulative ones like those who run SpaceX

I don't think you know anything about the space industry. SpaceX is famous for being wildly easier to work with than any other launch provider (including semi-national providers like Arianespace).

Famous among who? Are you in the space launch industry?

Is it possible that cheaper and more frequent launches will keep and up dropping the development prices as maybe more regular launches will enable the development process to be less strict and leave more room for error?

That is essentially what's driving the popularity of smallsats and megaconstellations. Since launch costs are dropping and flights are becoming more regular (eg SpaceX's transporter flights, where the rocket flies regardless of payload readiness and anyone who wasn't ready just moves to another flight, eliminating the main issue from other rideshare arrangements), it's potentially cheaper to make more replaceable satellites. So far this mainly applies to Earth observation and internet constellations.

This doesn't really carry-over to large projects like JWST yet though.

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