JWST Countdown To Terror 😳

[UKDiver]

32 minutes ago, Alien 13 said:

I am scared now, would feel safer with a Musk or Russian launch 😱

Alan

I think it won't fit inside a Falcon. It just fits the Ariane.

[Sunshine]

Some may be interested in this cool breakdown of some of Webb’s systems.

 

Edited December 24, 2021 by Sunshine

[nfotis]

On 17/12/2021 at 03:28, johninderby said:

A repair mission would be possible if NASA got the billions in funding that would be needed but might be cheaper to build a new more advanced telescope. 

JWST isn't repairable.

It isn't designed for that, in contrast to Hubble (the latter had lots of grabbing irons and oversize screw heads for handling via astronaut thick gloves etc).

You see, because they exhausted the JWST mass budget very early early (mission creep and all that), they had to cut weight everywhere. And that included removing screws everywhere possible.

So, they are using mostly glue for the assembly of the scope. If they found some broken item, they would have to disassemble (unglue) it first, replace the problematic items, then reassembly using glue etc. And there's just no way to replace subsystems in it, no rails and slots for that - it's extremely tight integration.

Even if a spaceship was able to reach JWST in the destination place/orbit at L2, how would it approach it without the engine exhausts damaging the extremely sensitive instruments? *Maybe* they could refuel the cooling liquid in order to keep one of the infrared instruments in operation. Maybe they could manage to refuel it in space etc.

I am pretty certain that JWST will be the last of its kind (and first). In the near future, boosters like the SpaceX Starship, Falcon Heavy, Vulcan, New Glenn etc could offer a much higher mass budget, which could permit a more robust and cheaper construction, with redundancy etc. A great part of JWST's cost came from testing and redesign within the strict mass budgets. Imagine if you had 60 tonnes of mass budget instead of 6 - you could use a heavier steel construction instead of exotic stuff, much more robust mechanisms for the sun shield, add cameras around the scope for self-monitoring, add 10 tonnes of fuel for orbital maneuvers etc.

N.F.

 

 

 

[UKDiver]

1 hour ago, Ags said:

Ariane has a superb launch record, the bigger risk is surely when JWST goes all origami in deep space.

I've been wondering about the origami working without gravity loads being the same as on earth. Can't test for that so easily.

[nfotis]

1 hour ago, Alien 13 said:

I am scared now, would feel safer with a Musk or Russian launch 😱

Alan

 

ESA participates on the JWST mission with the contribution of an Ariane 5 and two of the four instruments, so the telescope was forced to be designed within the volume and mass constraints of the Ariane 5 fairing and mass capabilities. NASA, ESA etc contribute to each other's mission usually 'in kind', without money being exchanged. Also, note that SpaceX wasn't available when JWST started being designed (and the recent launch failures of the Proton didn't inspire much confidence, I suppose).

The management of the JWST project by NASA was a near disaster, as the mass budget was exhausted quickly, and there was no room for making a more robust sun shield system. The cost skyrocketed as a result, and JWST has been termed "The scope that ate astronomy", because all the NASA budget available for the various astronomy projects has been drained by this program.

If the launch and mission is a success, few will complain. But the hard lessons from the JWST management haven't been lost on NASA on other groups, with WFIRST telescope (based on a donated tube from NRO) was more tightly managed, and when mission creep raised its ugly head, there were measures to limit the scope to the original specifications.

There are two nice press kits in multiple languages from Arianespace and ESA (I put the English versions below):

https://arianespace.com/wp-content/uploads/2021/12/VA256-launchkit-EN.pdf

https://esamultimedia.esa.int/docs/science/Webb-LaunchKit_EN.pdf

N.F.

Edited December 24, 2021 by nfotis

[kirkster501]

No matter what guys, less than four hours to go….. gosh, I’m nervous enough, never mind the people who have devoted their lives to this telescope. 

[UKDiver]

31 minutes ago, kirkster501 said:

No matter what guys, less than four hours to go….. gosh, I’m nervous enough, never mind the people who have devoted their lives to this telescope. 

I've a friend who has spent the last 10 years or so studying and working to get access to JWST data. I hope for their sake that launch etc is a success. A stressful time for many.

[Ags]

I thought JWST data would all be public domain?

[kirkster501]

41 minutes and counting and the veg needs to go on.....🙈

[Davey-T]

25 years in the making now 25 minutes to go 🤞

[Mognet]

If anyone hasn't found it yet, live launch coverage here. Not long to go!

 

[kirkster501]

Watching it on my iPad in the kitchen! 

[Sunshine]

It’s 7am Christmas morning here, last night I ate too much, surely too much wine too,but my alarm was set, I wasn’t going to miss this. All last night family members asked “so who’s this James Webb guy you keep talking about”

[Space Hopper]

The weather looks a bit dicey there, like theres a storm brewing.....??

[Chris]

Anyone else got butterflies!? I think it will be ok unless there's lightning. 

 

[Ian McCallum]

15 hours ago, JeremyS said:

And I was thinking it was the Brussels sprouts …

Genuine rocket fuel, along with cauliflower and cheese sauce!🤣

[kirkster501]

The number of software systems running at the moment in mission control, on JWST itself and in the Ariane must be incredible.

[kirkster501]

Everyone in the family watching it...!

I've got to take the turkey out, doh....

[Sunshine]

Here we go everyone! Oh my gosh 

[Swoop1]

No turning back now!

[ONIKKINEN]

No 10 billion dollar fireworks! Lets hope the space origami works out.

[kirkster501]

So far so good.  Proper separation will be key 😱

[Dave Lloyd]

30 minutes ago, kirkster501 said:

Everyone in the family watching it...!

I've got to take the turkey out, doh....

Apart from washing dishes, mopping up spills etc I'm banned from the kitchen on Christmas morning so I've been able to watch it all.  At least it wasn't bothered by the clouds unlike the rest of us. 

[UKDiver]

I'm quite happy it was delayed until today. Newton's birthday.

[Sunshine]

It’s away!!