JWST Countdown To Terror 😳

[reezeh]

6 hours ago, Mr Spock said:

Great word isn't it. I must try and work it into some conversations 😜

Maybe you need to work it into some Scrabble games.

 

On a new note I wonder if the shuttle was still available if the JWST could have been configured in low earth orbit then pushed out saving a load of fuel for the mission. Perhaps that might have been the original plan;  I don't know. It's a thought though if nothing else. 

[reezeh]

6 hours ago, Zermelo said:

and you mentioned previously that they will sequence the successful observation requests in the most fuel-efficient order. It sounds a bit like a travelling salesman type problem.

They've probably compiled and sorted a list even before they got near testing phase on the ground. Or at least I hope they have.

Problem with that is going to be what of anything new that deviates from the list more than a small amount, like say a sudden new exoplanet that just demands attention 

[dannybgoode]

Looks like the sun shield is now deployed and is ready for tensioning  . Fingers crossed this all goes to plan. I am also hoping that it’s not a case of the really difficult bits going fine only for a snag on what should be a relatively straightforward part of the deployment 🥴

[kirkster501]

1 hour ago, dannybgoode said:

Looks like the sun shield is now deployed and is ready for tensioning  . Fingers crossed this all goes to plan. I am also hoping that it’s not a case of the really difficult bits going fine only for a snag on what should be a relatively straightforward part of the deployment 🥴

Yes agreed.  Just imagine, all the preconceived "problem" parts deploy just fine and then there's an issue with the, say, steering mirror.  That's why test, test and test again (and then test some more [and then maybe again]) was so important and why it cost so much to develop and build.

[markse68]

such a shame they didn’t put a couple of small cameras on it- bet they wished they had when switches didn’t signal when they were unfurling these membranes- “When switches did not trigger to indicate the sunshield covers were rolled up, team members used temperature data & gyroscope sensors to confirm that they had.” 😬 

[johninderby]

Read a report that said adding external camers would be too expensive. Yeah right they only had a $ 10 billion budget. 🙄

[Rusted]

27 minutes ago, johninderby said:

Read a report that said adding external cameras would be too expensive. Yeah right they only had a $ 10 billion budget. 🙄

Guilt? They didn't want anybody to see their deliberate mistakes. Nor where the gaffer tape was already lifting.
A live camera feed would be invaluable to see what went wrong at any stage and what might just fix it.
The main problem might be relaying the imagery back to a rapidly receding Earth.
Do you really want a dish dangling off your toy during deployment?
 

[kirkster501]

The reason given by NASA is that such cameras and their required wiring would add too much extra launch mass to a system already at the limit of what Ariane was capable of when the decision was made. Every few grammes of weight is critical.  Also the additional software needed to control the cameras, adding further complications to an already incredibly sophisticated and expensive system hardware and software.  There are a ton of other sensors and they can infer what they need to know to work around a problem from those.  That is the NASA official answer to that question which has been asked of them a load of times.

It would have been great to see stuff going on.

Edited January 1, 2022 by kirkster501

[ONIKKINEN]

Live video coverage with decent cameras and multiple angles is a fairly recent thing from SpaceX i think. Since they are a commercial launch company they literally make their money on public relations, like pretty videos from space.

JWST has been in development for longer than the concept of HD-video has been available (not kidding!) so this was probably not even considered in the design phase. Obviously they could add cameras later but this just adds complexity, mass and has no real mission benefit. Im sure there is a sensor for everything that could go wrong already in place and a camera would just be redundant. Also i think JWST is such a big thing now because it has been delayed for an eternity. Had it launched in 2018 as intended i dont think there would have been such a fanfare surrounding this and the public coverage would have been a lot smaller.

[Captain Scarlet]

Tomorrow is when things start to get tense (hopefully)

[kirkster501]

5 minutes ago, Captain Magenta said:

Tomorrow is when things start to get tense (hopefully)

They said it would take two days to tension all of the membranes so we should hopefully find out tomorrow, as you say.  Fingers crossed!

[kirkster501]

...hmmm, they said they had the day off today.

Webb Sunshield Tensioning To Begin Tomorrow – James Webb Space Telescope (nasa.gov)

That makes me thing have they hit a problem and want more time????  There was never any talk of days off in the middle of this critical deployment.  What do you think?

[Stu]

1 minute ago, kirkster501 said:

...hmmm, they said they had the day off today.

Webb Sunshield Tensioning To Begin Tomorrow – James Webb Space Telescope (nasa.gov)

That makes me thing have they hit a problem and want more time????  There was never any talk of days off in the middle of this critical deployment.  What do you think?

I suspect the mid boom deployments took longer than expected and they just wanted a bit of slack in between. Let’s hope so anyway.

[ONIKKINEN]

2 minutes ago, kirkster501 said:

...hmmm, they said they had the day off today.

Webb Sunshield Tensioning To Begin Tomorrow – James Webb Space Telescope (nasa.gov)

That makes me thing have they hit a problem and want more time????  There was never any talk of days off in the middle of this critical deployment.  What do you think?

I sure hope no problems were found...

A human factor would be just to allow the team some well deserved rest in the midst of what must be a horroshow for the team responsible. JWST will spend a while on the way anyway, so why the rush? Thats what i hope anyway.

[sloz1664]

I would have thought that if any there are issues "time off" would be the last thing on their minds.

Steve

[Captain Scarlet]

Also I guess the levels of personal stress would be something they cannot have yet experienced. The consequence of a fault in testing is not fatal, and would have led to a fix. Now of course it’s that much more consequential.

[johninderby]

Simple explanation here. A sensor glitch had delayed things and the team had to work late so a day off was thought best. You don’t want a tired team doing the next step.

“Spacecraft managers added the pause in the sunshield deployment after working late into the night Dec. 31 to extend two “mid-boom” structures on either side of the spacecraft. Those booms extended the sunshield to its full size. That process started late when sensors indicated that a sunshield cover had not fully rolled up. Controllers decided to go ahead with the deployment of the booms because other data, including from temperature sensors and gyroscopes, were consistent with the removal of the cover.

“The team did what we had rehearsed for this kind of situation: stop, assess and move forward methodically with a plan,” said Keith Parrish, JWST observatory manager at the Goddard Space Flight Center, in a Dec. 31 statement. “We still have a long way to go with this whole deployment process.”

Edited January 1, 2022 by johninderby

[kirkster501]

^^^Hope you are right guys, it makes sense what you say.

I've captured it again this evening.  Will share tomorrow.

[johninderby]

Just a thought. Wonder if Hubble could take some close up pics of the JWST to confirm things are on track. 🤔

[sloz1664]

17 minutes ago, kirkster501 said:

^^^Hope you are right guys, it makes sense what you say.

I've captured it again this evening.  Will share tomorrow.

Nice one Steve. I was really impressed with your first effort & especially with the Nottingham weather of late.

[Ags]

1 hour ago, ONIKKINEN said:

I sure hope no problems were found...

I have never known NASA to dissemble relating to technical mission issues. I'm certain the delay really is just to give the team a rest.

[discardedastro]

I'll add to the camera discussion - NASA's been doing a lot of complex missions with little or no imagery for a very long time. You can make lots and lots of inferences with high confidence in space with well-known systems and good data, and JWST is probably the most overanalysed (and well-instrumented) bit of kit in space right now.

I'm sure this is just to let everyone rest. Human factors are well understood to be a major cause of failure in any operational environment, and sending everyone home to sleep and giving some of the support teams a bit more time to think is definitely the right message to give everyone working on the thing - take your time, don't rush, nothing's time-critical, get it right, and we're not going to stick to the schedule if it needs to move out a bit.

Absolutely sensible engineering - humans are part of the system too!

[Gfamily]

1 hour ago, johninderby said:

Just a thought. Wonder if Hubble could take some close up pics of the JWST to confirm things are on track. 🤔

I think the HST is moving much too quickly in its orbit to be able to get much of an image.  It would need to slew at a very a-typical rate to be able to image something only a few 100,000 km away. Given the very recent issues with HST itself,  they wouldn't want to risk running the existing 'best space telescope' outside its normal use case envelope for an uncertain gain.

[F15Rules]

1 hour ago, kirkster501 said:

...hmmm, they said they had the day off today.

Webb Sunshield Tensioning To Begin Tomorrow – James Webb Space Telescope (nasa.gov)

That makes me thing have they hit a problem and want more time????  There was never any talk of days off in the middle of this critical deployment.  What do you think?

C'mon guys..it's New Year!! The guys were obviously hung over!!🥴🤗😊

Dave

[Ags]

In space they can't hear you PARTY!!!!