# James Webb Space Telescope general discussion thread **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Tags:** science-math\ **Created:** [December 25, 2021, 1:18pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624 "2021-12-25T13:18:56Z")\ **Posts on this page:** 20\ **Page:** 4
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [December 29, 2021, 1:29am UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/61 "2021-12-29T01:29:07Z")
I’m sure not. It would have to be quite far away and would add lots of weight and complexity for no good reason. The Mars rovers can take selfies because the cameras are there anyway. ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [December 29, 2021, 1:40am UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/62 "2021-12-29T01:40:00Z")
> [@Jackknifed\_Juggernaut](#): > > Is there, or will there be a camera, focused on the telescope itself, allowing us to view it? Probably wouldn’t be very exciting once it’s fully operational, but still. I asked that question earlier. I looked through the JWST docs and FAQ, and found no reference to local cameras for insoecting the thing. I guess it’s not surprising given that the design dates back to 1996. ---
**Author:** ![TroutMan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/troutman/32/6721_2.png) [@TroutMan](https://boards.straightdope.com/u/TroutMan)\ **Post date:** [December 29, 2021, 2:12am UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/63 "2021-12-29T02:12:38Z")
> [@wolfpup](#): > > One strange thing – I read that we would be getting hot side and cold side temperature readings within one to two days after launch. It’s been three and a half days and still no temperature telemetry, at least not on the real time reporting site. There isn’t a hot side/cold side until the sun shield is deployed, is there? I think it more likely we’d get readings 1-2 days after the shield is completely unfurled. ---
**Author:** ![Jackknifed\_Juggernaut](https://avatars.discourse-cdn.com/v4/letter/j/9de053/32.png) [@Jackknifed\_Juggernaut](https://boards.straightdope.com/u/Jackknifed_Juggernaut)\ **Post date:** [December 29, 2021, 2:40am UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/64 "2021-12-29T02:40:00Z")
> [@Sam\_Stone](#): > > I guess it’s not surprising given that the design dates back to 1996. Considering there were already cameras on the moon to record the first lunar walk, I’m sure someone must have thought of it. 😉 ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [December 29, 2021, 2:55am UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/65 "2021-12-29T02:55:53Z")
> [@Jackknifed\_Juggernaut](#): > > Considering there were already cameras on the moon to record the first lunar walk, I’m sure someone must have thought of it. 😉 It’s a matter of weight, cost, and complexity. Today you could festoon a probe with a dozen tiny cameras on a simple serial bus without adding much weight and complexity. In 1996, not so much. ---
**Author:** ![pjd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pjd/32/3009_2.png) [@pjd](https://boards.straightdope.com/u/pjd)\ **Post date:** [December 29, 2021, 3:21pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/66 "2021-12-29T15:21:09Z")
> [@Jackknifed\_Juggernaut](#): > > Is there, or will there be a camera, focused on the telescope itself, allowing us to view it? We could use the Hubble telescope for that ! Could they not have sent it (JWST) up to earth orbit, then deployed all the bits, and then push it out to L2, so there’d be some possibility of fixing anything that didn’t deploy successfully ? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 29, 2021, 3:34pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/67 "2021-12-29T15:34:24Z")
They could have gone that route, but that’d mean giving it a high-acceleration rocket burn with all of the bits fully deployed, so the deployed configuration would have to be stronger. Or you could use a lower acceleration burn, but those are less efficient. There are always tradeoffs. ---
**Author:** ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)\ **Post date:** [December 29, 2021, 3:39pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/68 "2021-12-29T15:39:28Z")
Making all the parts fixable in space would’ve complicated the design a lot and probably made the payload a lot larger. Not having to worry about repairability probably freed up significant constraints for the engineers to design a smaller package. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [December 29, 2021, 4:36pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/69 "2021-12-29T16:36:17Z")
> [@wolfpup](#): > > I read that we would be getting hot side and cold side temperature readings within one to two days after launch. Temperature data is now up. > **[Where Is Webb? NASA/Webb](https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html)** > > During Webb's launch, deployment and commissioning, 'WhereIsWebb' tracked Webb's 'flight' to L2 orbit, its state and progress during its deployment and commissioning process, and finally the release of its first images. This process is now complete.... ---
**Author:** ![k9bfriender](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k9bfriender/32/3283_2.png) [@k9bfriender](https://boards.straightdope.com/u/k9bfriender)\ **Post date:** [December 29, 2021, 4:45pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/70 "2021-12-29T16:45:03Z")
There also would be no possibility of fixing it as we don’t have a space vehicle that is capable of doing so. Even if it were in orbit, and all it needs is a bit of elbow grease, we simply don’t have the capability of doing so. If we still had the space shuttle, or a similarly capable replacement, then maybe we could, and such a consideration would have been given more weight. ---
**Author:** ![squeegee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/squeegee/32/14537_2.png) [@squeegee](https://boards.straightdope.com/u/squeegee)\ **Post date:** [December 29, 2021, 4:56pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/71 "2021-12-29T16:56:24Z")
> [@k9bfriender](#): > > we don’t have a space vehicle that is capable of doing so. There was some discussion in another thread that I can’t seem to find that Orion + the European Service Module might possibly maaybe be able to reach JWST on a mission, but there’s damn little it could do once it got there. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [December 29, 2021, 7:26pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/72 "2021-12-29T19:26:52Z")
> [@Riemann](#): > > Temperature data is now up. Thanks for that. I actually check that site quite obsessively, and it just happened to come up in between my obsessive checking! For anyone who may not have noticed: Clicking anywhere on the temperature readings brings up a pop-up that describes the a, b, c, d measurement points. Clicking on some of the other information also brings up descriptive pop-ups. Also, if you scroll down to “Explore Deployments”, it takes you to a screen where you can horizontally scroll and take an advance peek at upcoming deployments. Further info that may be of interest to some: on the main status screen, “secondary mirror deployment” is when the three support struts for the secondary mirror swing out and hold it in position (the secondary mirror reflects the focused light back into the instrument package at the base of the primary mirror; it doubles the focal length in a compact package, somewhat like a Schmidt-Cassegrain telescope). “Primary mirror deployment” is the swinging out of the left and right “wings” of the primary mirror. The “mirror segments” phase is the initial adjustments of all the hexagonal mirror segments. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [December 29, 2021, 10:17pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/73 "2021-12-29T22:17:19Z")
Course correction burns after Ariane are minimal, so there’s enough fuel to last beyond 10 years. [NASA Says Webb’s Excess Fuel Likely to Extend its Lifetime Expectations – James Webb Space Telescope](https://blogs.nasa.gov/webb/2021/12/29/nasa-says-webbs-excess-fuel-likely-to-extend-its-lifetime-expectations/) ---
**Author:** ![outlierrn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/outlierrn/32/3005_2.png) [@outlierrn](https://boards.straightdope.com/u/outlierrn)\ **Post date:** [December 30, 2021, 4:27am UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/74 "2021-12-30T04:27:15Z")
[CometJwst\_Matipon\_1080.jpg (1080×721) (nasa.gov)](https://apod.nasa.gov/apod/image/2112/CometJwst_Matipon_1080.jpg) NASA released this photo of the launch with the comet Leonard, which is pretty damn cool. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [December 30, 2021, 7:41am UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/75 "2021-12-30T07:41:15Z")
> [@outlierrn](#): > > NASA released this photo of the launch with the comet Leonard, which is pretty damn cool. Do you know where that pic was taken, or do you have a cite with more information? That’s pretty damn cool indeed. > [@Riemann](#): > > Temperature data is now up. That’s pretty damn cool too (at the Instrument Radiator in particular). ---
**Author:** ![outlierrn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/outlierrn/32/3005_2.png) [@outlierrn](https://boards.straightdope.com/u/outlierrn)\ **Post date:** [December 30, 2021, 4:27pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/76 "2021-12-30T16:27:20Z")
It was taken in Thailand and also shows a pagoda in Doi Inthanon National Park [Comet Leonard soars behind the plume from NASA’s James Webb Space Telescope launch | Daily Mail Online](https://www.dailymail.co.uk/sciencetech/article-10347275/Comet-Leonard-soars-plume-NASAs-James-Webb-Space-Telescope-launch.html) ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [December 30, 2021, 4:35pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/77 "2021-12-30T16:35:39Z")
What and when is the next critical deployment? ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [December 30, 2021, 4:41pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/78 "2021-12-30T16:41:02Z")
> [@Hari\_Seldon](#): > > What and when is the next critical deployment?   The next major deployments all have to do with the sun shield. The protective cover should be removed and rolled up later today. In the following days, various sun shield booms come out and finally the sun shield is tensioned. ---
**Author:** ![squeegee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/squeegee/32/14537_2.png) [@squeegee](https://boards.straightdope.com/u/squeegee)\ **Post date:** [December 30, 2021, 5:05pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/79 "2021-12-30T17:05:39Z")
> [@wolfpup](#): > > > [@Hari\_Seldon](#): > > > > What and when is the next critical deployment? > > The next major deployments all have to do with the sun shield. The protective cover should be removed and rolled up later today. In the following days, various sun shield booms come out and finally the sun shield is tensioned. Nasa animation of the full deployment, including what happens on what day [![](https://img.youtube.com/vi/RzGLKQ7_KZQ/hqdefault.jpg "James Webb Space Telescope Deployment Sequence (Nominal)") ](https://www.youtube.com/watch?v=RzGLKQ7_KZQ) ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [December 30, 2021, 6:57pm UTC](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624/80 "2021-12-30T18:57:42Z")
> [@wolfpup](#): > > The next major deployments all have to do with the sun shield. The protective cover should be removed and rolled up later today. Done. [Previous page](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624.md?page=3) [Next page](https://boards.straightdope.com/t/james-webb-space-telescope-general-discussion-thread/956624.md?page=5)