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James Webb is fully deployed

nasa.gov

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Re: James Webb is fully deployed

#271

Post by heavenlyblue »

idealmedtech wrote: post #266
frosted-flakes wrote: post #234

Earlier quoted context omitted.

With Hubbles's highest resolution optics, the JWST will be about one-tenth the size of a pixel.

How can it make out galaxies at billions of light years away, but not a truck sized craft at a few million miles? I haven't done the math myself, so I'm certain one side of that equation is wrong, but that seems hard to believe!

It’s interesting that you are expressing an opinion about something that you could calculate in the same amount of time it took to write down that opinion.

Re: James Webb is fully deployed

#272

Post by weaksauce »

jl6 wrote: post #192

More great news. Congratulations to all who have worked on the project. I understand the reasons for not putting a camera on or near the JWST, but I’m still a little sad that we’ll probably never get to see the thing in situ in all its operational glory. Maybe one day when it finally expires, we can launch a “sample return” mission to tow it back.

the plan as i understand it is to have a drone refuel it after about 10 years or so... that might have a camera on it perhaps?

Re: James Webb is fully deployed

#273

Post by weaksauce »

heavenlyblue wrote: post #271
idealmedtech wrote: post #266

Earlier quoted context omitted.

How can it make out galaxies at billions of light years away, but not a truck sized craft at a few million miles? I haven't done the math myself, so I'm certain one side of that equation is wrong, but that seems hard to believe!

It’s interesting that you are expressing an opinion about something that you could calculate in the same amount of time it took to write down that opinion.

It seems like they are going for the "the easiest way to get a right answer is give the wrong answer on the internet" approach.

Re: James Webb is fully deployed

#274

Post by Spare_account »

idealmedtech wrote: post #266
frosted-flakes wrote: post #234

Earlier quoted context omitted.

With Hubbles's highest resolution optics, the JWST will be about one-tenth the size of a pixel.

How can it make out galaxies at billions of light years away, but not a truck sized craft at a few million miles? I haven't done the math myself, so I'm certain one side of that equation is wrong, but that seems hard to believe!

>a truck sized craft at a few million light years?

JWST is three light seconds from earth

Re: James Webb is fully deployed

#275

Post by weaksauce »

dredmorbius wrote: post #239
divbzero wrote: post #232

Earlier quoted context omitted.

Since L2 is an unstable equilibrium, won’t there also need to be routine adjustments throughout the mission?

Yes. Those adjustments, as well as unloading of the reaction wheels used to position JWST, and the fuel burns reqiured for them, are the principle determinants of the JWAT's lifespan, estimated at 10 years. Nasa have lowballed such estimates for numerous missions in the past (Hubble and numerous Mars lander and rover missions come to mind), and it's possible JWST will exceed the planned lifetime, potentially by a wid…

I was under the impression that they were planning on making a drone that would refuel it in 10 years or so? Is that not correct?

Re: James Webb is fully deployed

#276

Post by Spare_account »

weaksauce wrote: post #273
heavenlyblue wrote: post #271

Earlier quoted context omitted.

It’s interesting that you are expressing an opinion about something that you could calculate in the same amount of time it took to write down that opinion.

It seems like they are going for the "the easiest way to get a right answer is give the wrong answer on the internet" approach.

Cunningham's Law

https://en.wikipedia.org/wiki/Ward_Cunningham#%22Cunningham'...

Re: James Webb is fully deployed

#277

Post by dheerendra73 »

idealmedtech wrote: post #266
frosted-flakes wrote: post #234

Earlier quoted context omitted.

With Hubbles's highest resolution optics, the JWST will be about one-tenth the size of a pixel.

How can it make out galaxies at billions of light years away, but not a truck sized craft at a few million miles? I haven't done the math myself, so I'm certain one side of that equation is wrong, but that seems hard to believe!

Well galaxies at billions of light years distance are also 100000s light years wide. Rest of the math you can do about resolution now!

Re: James Webb is fully deployed

#278

Post by newman8r »

bichiliad wrote: post #250
JohnBooty wrote: post #208

Earlier quoted context omitted.

Great blog post from NASA themselves explaining it: https://blogs.nasa.gov/webb/2022/01/06/why-doesnt-webb-have-... the post is really not very long and I would suggest getting it straight from the horse's mouth, but for those not willing to devote a click here are arguably the most relevant bits! "deployment surveillance cameras would not add significant information of value for engineering teams commanding the spac…

One thing they mentioned that kinda sends it home to me is that the telescope is aimed at the dark and away from the sun, and the other side is especially reflective[0]. In other words, one side is too dark to see, and the other is too bright to see. [0]: https://twitter.com/NASAWebb/status/1479161991252131841

Couldn't they just use an image intensifier tube for night vision? I think they should just stick with the excuse of it being costly and unnecessary.

Re: James Webb is fully deployed

#279

Post by smoe »

_Microft wrote: post #114
WalterBright wrote: post #75

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?

Why spend money on JWST 2 when you could as well spend it on ... LUVOIR ? ^^ https://en.wikipedia.org/wiki/Large_Ultraviolet_Optical_Infr...

There are several space telescope projects under consideration besides luvoir.

Habitable Exoplanet Imaging Mission https://en.wikipedia.org/wiki/Habitable_Exoplanet_Imaging_Mi...

Lynx X-ray Observatory https://en.wikipedia.org/wiki/Lynx_X-ray_Observatory

Origins Space Telescope https://en.wikipedia.org/wiki/Origins_Space_Telescope

Re: James Webb is fully deployed

#280

Post by xvector »

weaksauce wrote: post #272
jl6 wrote: post #192

More great news. Congratulations to all who have worked on the project. I understand the reasons for not putting a camera on or near the JWST, but I’m still a little sad that we’ll probably never get to see the thing in situ in all its operational glory. Maybe one day when it finally expires, we can launch a “sample return” mission to tow it back.

the plan as i understand it is to have a drone refuel it after about 10 years or so... that might have a camera on it perhaps?

I thought there were no plans for any refuel or repair mission.
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