Curious did they do a sample data with current temp? Since the deployment is complete. I know it will be not as good as at L2, but still.
James Webb is fully deployed
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Re: James Webb is fully deployed
#212Earlier quoted context omitted.
> double the data Yes, but the data has diminishing returns as well. The real value in a second unit is having a backup in the event of a total failure of the first. But that's a hard sell to the taxpayers who fund these things.
> Yes, but the data has diminishing returns as well. I find that hard to believe considering there's literally a universe of things to look at. We find surprising things everywhere we look.
It's not quite the same thing, but as an analogy: should we have built two CERNs (edit: LHCs, not CERNs) to "find" the Higgs boson faster? Or was it better just to build one, expecting that it had a good chance of finding the particle and other new physics, and then put future funding toward different/more advanced and capable instruments that will give us a window into even higher energies/entirely new observation spaces, rather than just accelerating our search of the same spaces by low integer multiples?
My understanding is that the JWST opens up new observation spaces, specifically very distant and highly redshifted objects that Hubble couldn't capture. So we should have a lot of data on a new class of objects in fairly short order, and thanks to the cosmological principle we can expect to see similar distributions of the same objects and phenomena no matter what direction we look in. As we gather more data, we will converge on an understanding of these new spaces, and eventually the error bars will shrink to the point where further observation is generally not giving us much new information.
Is it better to build more JWSTs, to accelerate that convergence by low integer multiples and similarly increase the chance that we'll happen to point one at something truly new and "surprising"? Or should we spend our money on bigger and more capable instruments that we know will give us access to entirely new observation spaces that are completely out of reach of the JWST and other extant instruments?
I don't think it would be such an obvious question, if we weren't constantly getting better and better at designing and launching large and complex instruments. As things stand, we can let JWST and its ilk blaze the trail, then follow up with cheaper instruments building on lessons learned and our general technological and economic progress.
Re: James Webb is fully deployed
#213Earlier quoted context omitted.
Honestly that doesn't sound like much money. Especially since these projects aren't solely funded by one country, even if one foots most of the bill. Also, $1bn over it's lifetime is really cheap even just for the US alone.
> Honestly that doesn't sound like much money Well by comparison, here is the cost of two of the most impactful recent-ish (post 2000) space telescopes the US has launched: - Spitzer: 700M$, JWST being it's successor. This telescope allowed us to detect an exoplanet through light for the first time, refine our understanding of the shape of the milky way, find candidate objects to be further observed by JWST and many…
Instead of comparing to other telescope projects maybe better to compare to other mega science projects. Or better yet, other government costs. Though of course we'd need to run a cost benefit analysis.
The thing is that these numbers are big for us and most companies, but these are government numbers and decades of work. Both factors are important. It's $11bn over 24 years, or 458m/yr. I'm happy to pay an extra $3/yr for this project.
Re: James Webb is fully deployed
#214Curious did they do a sample data with current temp? Since the deployment is complete. I know it will be not as good as at L2, but still.
They have to wait for the instruments to cool down some more first. Data is expected in 5-6 months.
Re: James Webb is fully deployed
#215Earlier quoted context omitted.
IMO your logic fits with large production runs. In space applications costs can be exaggerated compared to actual production environments because the risks aren’t mitigated by something like the FAA, meaning they are often mitigated by some downstream process. Besides, a lot of the the designs already include critical spares, so there’s more than a single run, even in a one-off design
So build a copy out of the spares! If they're there, they're already paid for.
Not every part meets the criteria to be a "critical" spare. You don't have a complete set of spares for every component.
Re: James Webb is fully deployed
#216I've never been one for being hyped about telescopes, but I am particularly excited about the images that this one will come up with.
What kind of images can we expect? I understood it's an infrared telescope. Will we get visually ... interesting images? Or just data?
Re: James Webb is fully deployed
#217Re: James Webb is fully deployed
#218Earlier quoted context omitted.
I'm hoping that the 5 months of calibration time is one of those where the engineers were asked "how long", so they thought about it and then padded the shit out of it, then the PMs took that number and padded it yet again. After all that, it only takes a few weeks. It'll be the first milestone JWST would meet early, so not too likely. We've only waited decades, so a few more months isn't that bad. At least it is off…
I can tell, you're an engineer. Of some variety.
I only play one on TV ;-)
Then again, it's not a unique situation for an engineer. It's the same for any situation for construction (and related jobs) estimates, auto-repair, etc. You always want to lean on over estimating time and finishing "early" vs the opposite.
Re: James Webb is fully deployed
#219Earlier quoted context omitted.
That doesn't sound right... > Carl Sagan played a leading role in the American space program since its inception. He was a consultant and adviser to NASA beginning in the 1950s, he briefed the Apollo astronauts before their flights to the Moon, and was an experimenter on the Mariner, Viking, Voyager, and Galileo expeditions to the planets. He helped solve the mysteries of the high temperature of Venus (a massive gree…
I've met Sagan (he came by our dorm for conversation and dinner with the students). He was a great man. He was wonderful to talk to. He has made great contributions to science. He deserves all the credit and accolades you mentioned. But I doubt he ever set foot in a machine shop. Making things is an entirely different skill.
Machine shop experience is not related project cost estimations.
Re: James Webb is fully deployed
#220Earlier quoted context omitted.
> Making two adds little cost. 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.
> huge costs in subsequent runs Often that's because they have to rebuild and reset the tooling. Within the run, though, the incremental cost should be minimal. The huge costs may be huge, but not huge compared to the cost of the prototype.
A lot of times when you make one of something, there's stuff you would make tooling for if you were going to do more than one, but which instead you do by hand. Sometimes this is even true in software, but not very often, because the advantages of being able to recompile something from source code are so huge.