141–150 of 522 posts
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Right, but NOVA said that running out of fuel ended Kepler.
It worked for 9 years and 7 months, whilst being planned to operate for 3,5 years, so beyond it's expected lifetime then.
BTW, I doubt there's enough experience with space hardware to accurately predict it's life, especially since each machine is a one-off.
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So that more researchers have access. Afaik access is shared and researchers have to make a proposal and get it approved before use, which to me suggests some kind of queue
Queueing researchers should be fine given the universe will be around for a while.
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Because it's a wrong assumption. Significant cost come from the assembly and testing of all the components itself, that you would have to redo entirely. Also if you were to build just 2 or 3 of them, you can't expect any economy of scale. On top of that, the operational cost of JWST is expected to be around 1B$ for it's lifetime, you could expect that to be similar for every single replica you have. And finally, you…
Assuming your figures are correct, you'll get double the data for another 30% cost. If you wait a month before launching #2, if problems appear in #1 (like the telescope mirror was ground improperly) it can be fixed in #2. The operational cost will not double. The same ground facility, equipment, and staff can manage both. If you're buying two identical launches, you can get a quantity discount. > the benefits of a s…
Sending just another similar telescope that provides more same typed data (wavelength, angular resolution) is probably not worth it. Spending the same sum for different type of telescope would be better use of the money.
Hubble, Hershel and Webb were are made for different wavelengths, they are complementary.
The Extremely Large Telescope (ELT) is ready around 2027 and it will be the next revolution. 0.005 arc-seconds compared to 0.1 arc-seconds of JWST. (978 m2 vs 25.4 m2 collecting area)
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This question comes up in every one of these threads and this is the correct response. If you look at the line items on a build, you might see something like a $200 bolt. It’s not that there was $198 of R&D going into the design of the bolt, it’s that quality management drives the cost. Chain-of-custody, bonding, material testing, witnessing etc. are all part of that effort and they don’t scale like a design spec doe…
If it's a one-off bolt with a custom design, it will likely cost thousands of dollars.
(I’ve worked in a custom machine shop for aerospace, and depending on the tolerances, the actual build is typically not thousands until you factor in all the aspects in my previous post)
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That's not entirely true. Any reasonably complex system will almost certainly have single points of failure, including airliners. Those single points of failures might be very unlikely, but they are still there. E.g. what if the front fell off?
It is entirely true. Source: I worked on 757 flight controls design for 3 years. > what if the front fell off? All structural components are redundant and have redundant attachments. The wing spars are doubled, for example.
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Because it's a wrong assumption. Significant cost come from the assembly and testing of all the components itself, that you would have to redo entirely. Also if you were to build just 2 or 3 of them, you can't expect any economy of scale. On top of that, the operational cost of JWST is expected to be around 1B$ for it's lifetime, you could expect that to be similar for every single replica you have. And finally, you…
Assuming your figures are correct, you'll get double the data for another 30% cost. If you wait a month before launching #2, if problems appear in #1 (like the telescope mirror was ground improperly) it can be fixed in #2. The operational cost will not double. The same ground facility, equipment, and staff can manage both. If you're buying two identical launches, you can get a quantity discount. > the benefits of a s…
I think you are overextending your experience in a production environment here.
I’ve worked in both, and the type of builds in these aerospace applications still have huge costs in subsequent runs. Hell, even rebuilding an existing component can be prohibitively expensive.
Much of the GSE was likely existing so that’s probably a non-issue.
Earlier quoted context omitted.
Because it's a wrong assumption. Significant cost come from the assembly and testing of all the components itself, that you would have to redo entirely. Also if you were to build just 2 or 3 of them, you can't expect any economy of scale. On top of that, the operational cost of JWST is expected to be around 1B$ for it's lifetime, you could expect that to be similar for every single replica you have. And finally, you…
Assuming your figures are correct, you'll get double the data for another 30% cost. If you wait a month before launching #2, if problems appear in #1 (like the telescope mirror was ground improperly) it can be fixed in #2. The operational cost will not double. The same ground facility, equipment, and staff can manage both. If you're buying two identical launches, you can get a quantity discount. > the benefits of a s…
I wouldn't be surprised though if we start to see clever design proposals coming down the pipeline, like several cheaper telescopes, swarm designs for giant radio telescope arrays, and even amateur designed and operated space telescopes. Remember that the JWST started it's design phase back in 1996, and the economics of space launches have changed considerably since then.
Earlier quoted context omitted.
Assuming your figures are correct, you'll get double the data for another 30% cost. If you wait a month before launching #2, if problems appear in #1 (like the telescope mirror was ground improperly) it can be fixed in #2. The operational cost will not double. The same ground facility, equipment, and staff can manage both. If you're buying two identical launches, you can get a quantity discount. > the benefits of a s…
Agree. A replica wouldn’t have to be sent to L2 for that matter. Pretty sure a lot of science could be done with even a slow trajectory leaving the solar system, if orbiting something else is infeasible.
Since 90% of the cost is probably in R+D of the telescope, one could build and deploy another for another 10%. Why isn't this done? Why is every space telescope completely unique?
> 90% of the cost is probably in R+D of the telescope While I might have guessed that, IIRC someone at NASA said that most of the cost is parts, assembly, and testing of a massive, highly sensitive, highly unusual custom build. Many (most?) parts are custom made, and even finding vendors to make them again would be difficult - wasn't the manufacturing completed several years ago? Again, IIRC, they said a second one m…