JWST Countdown To Terror 😳

[kirkster501]

A week on Wednesday it is set to launch.

Just so many single points of failure.  In most engineering systems we try to eliminate as many of these as possible to reduce as much entropy in the system as possible.  On JSWT there are a dozen mission critical failure points with no backup, to say nothing of the launch itself.  The most critical:

1. The High gain antenna HAS to deploy as do the solar panels.  Pretty low entropy there but they can never take anything for granted.

2. If the sun shield doesn't fully deploy there will still be a mission but a drastically degraded one

3. The bus tower HAS to rise up

4.  The secondary mirror HAS to deploy - zero mission otherwise.

5.  At least one side of the foldable mirror HAS to fold out.   JWST needs at least 15 segments.

6. The radiator HAS to open

Pls others 😱

Gee whiz, scary stuff or what?!!!!!  Let's all keep our fingers crossed.  If it works it is going to be a bonanza of astronomy science this next few years

Has everyone got a launch pass to view it live next week?

Steve

Edited December 14, 2021 by kirkster501

[kirkster501]

James Webb Space Telescope Registration, Wed, Dec 22, 2021 at 7:20 AM | Eventbrite

[Alien 13]

I dont hold out much hope for a successful mission, I will be pleased if I am proved wrong though..

Alan

[Stu]

1 minute ago, Alien 13 said:

I dont hold out much hope for a successful mission, I will be pleased if I am proved wrong though..

Alan

Looking on the bright side 😉

I’m just keeping my fingers crossed that all goes well. All those years of hard work put in by hundreds of engineers deserve some luck! 🤞🤞

[kirkster501]

I know Alan.  I am equally terrified, I must say! 

[Alien 13]

5 minutes ago, Stu said:

Looking on the bright side 😉

I’m just keeping my fingers crossed that all goes well. All those years of hard work put in by hundreds of engineers deserve some luck! 🤞🤞

I used to run the testing facilities for a lot of MOD and aerospace projects and I know how hard it is to cover every eventuality no matter how many hundreds of hours you put in, its obviously harder still when you are at the cutting edge..

Alan

[Richard_]

Could you imagine the size of their FMEA for the entire mission and individual components?!

[Stu]

3 minutes ago, Alien 13 said:

I used to run the testing facilities for a lot of MOD and aerospace projects and I know how hard it is to cover every eventuality no matter how many hundreds of hours you put in, its obviously harder still when you are at the cutting edge..

Alan

Yes, it’s hugely challenging I know. I find it annoying when the ‘masses’ assume these things are easy, and that very clever scientists are ‘stupid’ when things go wrong! The complexity is ludicrous and all we can do is hope that all goes to plan.

[tomato]

They’ve deployed and folded it up that many times on the ground, a lot of components must be someways into their working life…

Still I’ll be willing it on next week and through the 30 days of terror.🤞🙏🙄

[Ags]

I'll watch the launch through my fingers.

[jjohnson3803]

1 hour ago, Alien 13 said:

I don't hold out much hope for a successful mission, I will be pleased if I am proved wrong though..

Strange.   I've been having this feeling that the thing is not going to get off the launchpad or crash after launch.  I thought I was just being a morose Finlander.

9 minutes ago, Ags said:

I'll watch the launch through my fingers.

Dr. Becky said in her latest video that she's going to hide behind her couch.

[Stu]

2 hours ago, jjohnson3803 said:

I thought I was just being a morose Finlander.

🤣🤣🤣

[Gfamily]

A further delay,  now "no sooner than 24th December "

https://blogs.nasa.gov/webb/2021/12/14/webb-space-telescope-launch-date-update

[kirkster501]

Would rather they get it right. Just imagine…. “who left the eye piece cover on?!”

[kirkster501]

13 hours ago, Richard_ said:

Could you imagine the size of their FMEA for the entire mission and individual components?!

It would be huge. Just imagine the decision tree.  IF x does not work THEN….   Imagine all the workarounds they must already have in place as contingencies.

[DaveS]

We need to be able to send people out to L2. Can you imagine the debacle if the HST had been launched to L2?

[Stu]

9 hours ago, Gfamily said:

A further delay,  now "no sooner than 24th December "

https://blogs.nasa.gov/webb/2021/12/14/webb-space-telescope-launch-date-update

Turkey roast served at desks I guess this year?

[Captain Scarlet]

52 minutes ago, Stu said:

Turkey roast served at desks I guess this year?

No chance. Can’t let pursuit of an expensive hobby get in the way of something as important as Christmas Dinner!

[kirkster501]

I can’t see it launching this side of Christmas now.

[Chris]

The facepalm that must have happened when they realised the Hubble was myopic (all down to a spec of dust on calibration equipment I believe!) and against all odds they 'popped' back up with a pair of specs and sorted it, amazing!

I basically have high hopes as long as the James Webb gets up there! Adrenaline wont be in short supply the day of the launch that's for sure!

[jock1958]

Bet your bottom dollar that all the systems including mission critical have back-ups and everything has been thoroughly tested, so I’ve every confidence that it will be a stunning success....however there’s always the great unknown or unseen element that can catch you out!!

Edited December 15, 2021 by jock1958

[Alien 13]

10 minutes ago, jock1958 said:

Bet your bottom dollar that all the systems including mission critical have back-ups and everything has been thoroughly tested, so I’ve every confidence that it will be a stunning success....however there’s always the great unknown or unseen element that can catch you out!!

The problem is that its easy to test individual components but not the whole payload as a complete entity, for example I doubt but maybe wrong that they could have got the whole thing into a HALT/HASS chamber capable of simulating the thermal shock as it leaves our atmosphere.

Alan

Edited December 15, 2021 by Alien 13

[jock1958]

4 minutes ago, Alien 13 said:

The problem is that its easy to test individual components but not the whole payload as a complete entity, for example I doubt but maybe wrong that they could have got the whole thing in a HALT/HASS chamber capable of simulating the thermal shock as it leaves our atmosphere.

Alan

I’m no rocket scientist but I’m hoping they’ve taken things like that into account especially the huge cost of it all, but like I say there’s always the great unknown so fingers crossed 🤞 

[tomato]

1 hour ago, Alien 13 said:

The problem is that its easy to test individual components but not the whole payload as a complete entity, for example I doubt but maybe wrong that they could have got the whole thing into a HALT/HASS chamber capable of simulating the thermal shock as it leaves our atmosphere.

Alan

It has been in the SES chamber  at Goddard so it's operation has been tested in space like conditions. I understand the nose cone fairing has some custom venting arrangements to reduce the pressure shock when the fairing is released, this might help lesson the thermal shock also? I guess they have engineered this into the design, even if they cannot test for it.

[Alan White]

Something that like so many have looked forward to for a long while

Something I think we all are equally concerned about as well

So let’s hope as well as all the fine science and engineering that has and is going on that Lady Luck is available at launch and deployment.