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I'm super excited by all these new prospects. With Starship and ..... SLS...... anyway.... coming online I'm extremely excited at the prospects of reusing JWST

I'm super excited by all these new prospects. With Starship and ..... SLS...... anyway.... coming online I'm extremely excited at the prospects of reusing JWST concepts/tech on larger arrays or larger single mirrors. A whole new upper limit of space telescopes unlocked.

credit_guy 3y ago
There's a cautionary tale there though. With Starship being able to ferry more than 100 tons into space (JWST = 12 tons), you can imagine how much cheaper it will be to launch telescopes in space. A lot of the cost of JWST was related to the need to make it foldable in complicated ways, and to make it vibration resistant, and in general compensate for the fact that current rockets are cramped. If you can put new telescopes inside a massive cargo ships, protect them with several dampeners, give them ridiculous amounts of space so there's no need for funky folding, how much cheaper can you get? My bet is that by the end of the decade we will have more multiple telescopes more powerful than JWST in the sky, built and launched at a cost below $100 million each, or 100 times cheaper than JWST. Yet, if you ask 100 people, both scientists and laypeople, mabye 99 will tell you that the $10 billion bill for JWST was worth it. I'm pro-science, but scientists refuse to even ask this question: when you ask for billions for a super-duper experiment (ITER, looking at you, post-CERN collider too), what is the chance that you could get the same experiment 30 years from now for 100 times less money? The Human Genome Project cost $2.7 million in the 90's, yet now one can sequence any genome for hundreds of dollars (if not less). At what point will scientists be willing to say that maybe the price for the JWST was too high?
- bigbillheck 3y ago
  I find it hard to believe that without all the immense effort of the HGP we'd have such cheap gene sequencing these days.
- ceejayoz 3y ago
  > I'm pro-science, but scientists refuse to even ask this question: when you ask for billions for a super-duper experiment (ITER, looking at you, post-CERN collider too), what is the chance that you could get the same experiment 30 years from now for 100 times less money? They'd correctly point out spending the money inventing the technology is precisely how it gets that cheap 30 years later. > At what point will scientists be willing to say that maybe the price for the JWST was too high? For context, the JWST cost us about as much as Americans spend on one Halloween. https://finance.yahoo.com/news/much-americans-spend-halloween-130034596.html https://finance.yahoo.com/news/much-americans-spend-hallowee...
  - tedunangst 3y ago
    But the money spent on JWST did not make the rockets bigger.
  - credit_guy 3y ago
    > For context, the JWST cost us about as much as Americans spend on one Halloween. That's a cute argument, but flawed. For any project, scientific or not, you need to estimate the return on investment and to survey the alternatives. With your argument it appears you can skip these things. If a project costs less than how much Americans spend on Halloween, then we just do it? By the way, for a lot of people Halloween is quite important. It must be, since they are willing to part with their money. But that's a choice each of them is free to make. Spending $10 billion on a science project that discovers some distant galaxies is a choice made by other people on their behalf. And when this happens it is the duty of those people to ask and answer some questions. Using your argument, it follows that the people who make that choice do not actually need to ask and answer the pertinent questions. Because, you know, science is always worth it. > They'd correctly point out spending the money inventing the technology is precisely how it gets that cheap 30 years later. They would certainly point that out, but incorrectly. In the case of JWST, none of the money spent on it resulted in technologies used by SpaceX to build the Starship.
    - ceejayoz 3y ago
      > They would certainly point that out, but incorrectly. In the case of JWST, none of the money spent on it resulted in technologies used by SpaceX to build the Starship. Sure; the Human Genome Project didn't help develop electric cars, either. JWST benefits the construction of future telescopes Starship may carry. Deployable sunshades and unfolding spacecraft will still be useful in Starship's larger payload sizes, as will the advances in optics etc. Again, the fundamental logical error you're making is that waiting 30 years will make technologies just... drop into our laps, fully formed. You mentioned ITER, for example, and implied we'd somehow just magically have cheap fusion power in a few decades without that sort of investment in research and development.
- martinclayton 3y ago
  I think the timeline and price tag are overly optimistic, but agree we can expect massive benefits from the lift capability of Starship. The cheapest big telescopes I could find with a quick trawl are the Hobby–Eberly Telescope and its "clone" the SALT. They cost about $20 million each, compared to similarly-sized telescopes in the $80 million-and-up price range. I doubt there's a project time-line since the 1970s from inception to first light of under 5 years, which would put us at 2029 already. Perhaps the aim should be to have lots of "good enough" unit instruments, rather than one world-beatingly big one that politicians or billionaires find stimulating to throw money at.
- dylan604 3y ago
  > At what point will scientists be willing to say that maybe the price for the JWST was too high? Any of them whose project was not funded because the money was tied up in funding JWST?
hn8305823 3y ago
I don't think larger single mirrors is going to be a thing. The numerous advantages of hexagon arrays far outweigh (pun intended) the single drawback of the large hexagonal diffraction spikes. The point spread function (PSF) is very well defined and can be easily worked around by some combination of PSF modeling, selecting a desired orientation, or multiple exposures. The Keck Telescope was the first major observatory to use this technique in 1993. https://en.wikipedia.org/wiki/Keck_telescope https://en.wikipedia.org/wiki/Keck_telescope
- topspin 3y ago
  > I don't think larger single mirrors is going to be a thing. With regard to optical light space telescopes, one iteration of a single large mirror would be a great advancement. Hubble is only 2.4m. Back when NASA was developing Ares V there were proposals for an 8m optical space telescope. You can still find vestiges of that at NASA[1] and various videos of the launch and deployment. Maybe that can still happen with Starship, SLS or whatever. Just need a big enough payload fairing. [1] https://ntrs.nasa.gov/citations/20100004890 https://ntrs.nasa.gov/citations/20100004890

credit_guy 3y ago

There's a cautionary tale there though. With Starship being able to ferry more than 100 tons into space (JWST = 12 tons), you can imagine how much cheaper it will be to launch telescopes in space. A lot of the cost of JWST was related to the need to make it foldable in complicated ways, and to make it vibration resistant, and in general compensate for the fact that current rockets are cramped. If you can put new telescopes inside a massive cargo ships, protect them with several dampeners, give them ridiculous amounts of space so there's no need for funky folding, how much cheaper can you get? My bet is that by the end of the decade we will have more multiple telescopes more powerful than JWST in the sky, built and launched at a cost below $100 million each, or 100 times cheaper than JWST. Yet, if you ask 100 people, both scientists and laypeople, mabye 99 will tell you that the $10 billion bill for JWST was worth it. I'm pro-science, but scientists refuse to even ask this question: when you ask for billions for a super-duper experiment (ITER, looking at you, post-CERN collider too), what is the chance that you could get the same experiment 30 years from now for 100 times less money? The Human Genome Project cost $2.7 million in the 90's, yet now one can sequence any genome for hundreds of dollars (if not less). At what point will scientists be willing to say that maybe the price for the JWST was too high?

bigbillheck 3y ago
I find it hard to believe that without all the immense effort of the HGP we'd have such cheap gene sequencing these days.
ceejayoz 3y ago
> I'm pro-science, but scientists refuse to even ask this question: when you ask for billions for a super-duper experiment (ITER, looking at you, post-CERN collider too), what is the chance that you could get the same experiment 30 years from now for 100 times less money? They'd correctly point out spending the money inventing the technology is precisely how it gets that cheap 30 years later. > At what point will scientists be willing to say that maybe the price for the JWST was too high? For context, the JWST cost us about as much as Americans spend on one Halloween. https://finance.yahoo.com/news/much-americans-spend-halloween-130034596.html https://finance.yahoo.com/news/much-americans-spend-hallowee...
- tedunangst 3y ago
  But the money spent on JWST did not make the rockets bigger.
- credit_guy 3y ago
  > For context, the JWST cost us about as much as Americans spend on one Halloween. That's a cute argument, but flawed. For any project, scientific or not, you need to estimate the return on investment and to survey the alternatives. With your argument it appears you can skip these things. If a project costs less than how much Americans spend on Halloween, then we just do it? By the way, for a lot of people Halloween is quite important. It must be, since they are willing to part with their money. But that's a choice each of them is free to make. Spending $10 billion on a science project that discovers some distant galaxies is a choice made by other people on their behalf. And when this happens it is the duty of those people to ask and answer some questions. Using your argument, it follows that the people who make that choice do not actually need to ask and answer the pertinent questions. Because, you know, science is always worth it. > They'd correctly point out spending the money inventing the technology is precisely how it gets that cheap 30 years later. They would certainly point that out, but incorrectly. In the case of JWST, none of the money spent on it resulted in technologies used by SpaceX to build the Starship.
  - ceejayoz 3y ago
    > They would certainly point that out, but incorrectly. In the case of JWST, none of the money spent on it resulted in technologies used by SpaceX to build the Starship. Sure; the Human Genome Project didn't help develop electric cars, either. JWST benefits the construction of future telescopes Starship may carry. Deployable sunshades and unfolding spacecraft will still be useful in Starship's larger payload sizes, as will the advances in optics etc. Again, the fundamental logical error you're making is that waiting 30 years will make technologies just... drop into our laps, fully formed. You mentioned ITER, for example, and implied we'd somehow just magically have cheap fusion power in a few decades without that sort of investment in research and development.
martinclayton 3y ago
I think the timeline and price tag are overly optimistic, but agree we can expect massive benefits from the lift capability of Starship. The cheapest big telescopes I could find with a quick trawl are the Hobby–Eberly Telescope and its "clone" the SALT. They cost about $20 million each, compared to similarly-sized telescopes in the $80 million-and-up price range. I doubt there's a project time-line since the 1970s from inception to first light of under 5 years, which would put us at 2029 already. Perhaps the aim should be to have lots of "good enough" unit instruments, rather than one world-beatingly big one that politicians or billionaires find stimulating to throw money at.
dylan604 3y ago
> At what point will scientists be willing to say that maybe the price for the JWST was too high? Any of them whose project was not funded because the money was tied up in funding JWST?

hn8305823 3y ago

I don't think larger single mirrors is going to be a thing. The numerous advantages of hexagon arrays far outweigh (pun intended) the single drawback of the large hexagonal diffraction spikes. The point spread function (PSF) is very well defined and can be easily worked around by some combination of PSF modeling, selecting a desired orientation, or multiple exposures. The Keck Telescope was the first major observatory to use this technique in 1993. https://en.wikipedia.org/wiki/Keck_telescope https://en.wikipedia.org/wiki/Keck_telescope

topspin 3y ago
> I don't think larger single mirrors is going to be a thing. With regard to optical light space telescopes, one iteration of a single large mirror would be a great advancement. Hubble is only 2.4m. Back when NASA was developing Ares V there were proposals for an 8m optical space telescope. You can still find vestiges of that at NASA[1] and various videos of the launch and deployment. Maybe that can still happen with Starship, SLS or whatever. Just need a big enough payload fairing. [1] https://ntrs.nasa.gov/citations/20100004890 https://ntrs.nasa.gov/citations/20100004890