What are you doing today?

AG_PhamD said:
Well, obviously the issue is cost, but I suspect the cost of constructing the the telescope and launching it is a fraction of its $10B cost. The development, many engineering complications, and many, many program delays due to funding made the program as expensive as it is. So to build another telescope with all the engineering sorted out and proper amount money allocated to build an additional unit should cost not that much more, relatively speaking. It’s pretty typical to build backup satellites, historically speaking.

They’re obviously going to have spare parts of things that’s could potentially fail on the ground. In fact, some parts are actually made in multiple batches, each batch is tested, and the best performing batch has those parts used. As it is, a lot of the sensors are those used (ir derivatives of) existing sensors on spacecraft. But as I’m sure you know, the JWST, unlike Hubble, will be hanging out in a place in space inaccessible for future repairs and does not inherently have a mechanism to dock to other spacecraft and if in fact we have a spacecraft to make it there (Orion possibly- though it lacks a way of manipulating the spacecraft).

There is no design to support to support a robotics fuel resupply mission, though that doesn’t mean it’s impossible. But it would likely be much more risky and dangerous. There was talk of adding an adapter so it could dock with other spacecraft, but that apparently doesn’t appear to have made the final design.

In that the JWST has almost 350 single point failures, and a bunch that are mission critical, I think having a backup would have a good idea. A lot can go wrong between now and deployment. Additionally, with as little as a 6 year lifespan due to the fuel limitations, if the primary program is successful the backup could be used to essentially extend the program as has been done with many space programs. If JWST fails (knock on wood) it’s pretty unlikely we’ll see a second one built.
Click to expand...
Not to belabor the point, but if the current mission were to fail and there were a backup plan and equipment in place, I'm sure there would be a lengthy investigation to determine how to avert failure the next time, which might involve expensive re-design. Then, too, with so many single points-of-failure, wouldn't there still be considerable risk on a second go-around?

In any case, I'm also enthusiastic about the JWST and hope that all the years of engineering will pay off with success. Webb's antenna assembly was deployed a couple hours ago. Apparently, it will allow downloading of at least 28.6 GB of data two times a day.
 
Roller said:
Not to belabor the point, but if the current mission were to fail and there were a backup plan and equipment in place, I'm sure there would be a lengthy investigation to determine how to avert failure the next time, which might involve expensive re-design. Then, too, with so many single points-of-failure, wouldn't there still be considerable risk on a second go-around?
Click to expand...

Yep. And quite a few components of the telescope's functionality were custom-made by hand, according to one of the newspaper articles I read about the decades-long implementation. So in the event of a later discovery that something had very laboriously been done wrong twice-- for the first go with an identical backup "just in case" -- NASA would probably receive a Congressional tongue-lashing worth tuning in to watch.

File all that under "damned if you do and damned if you don't", I guess.

Bill Nelson was right in emphasizing yesterday that a venture with potentially vast rewards usually comes with great risks as well. American taxpayers are not always good at remembering that, and politicians up for re-election even less so. It's weird too, because private industry supposedly understands the need for risk taking, at least until their IPO occurs and lets ordinary shareholders in on the measuring of how much risk is warranted by the prospect of an adequate reward.

We Americans also like to hang onto a sort of "origins story" of ourselves as rugged frontiersmen, ever at the forefront of risk and peril in building a better nation. We act, however, like it's way more fun to watch TV re-enactments of such tales of old, rather than to reach into our pockets to help fund the modern-day versions.

Roller said:
In any case, I'm also enthusiastic about the JWST and hope that all the years of engineering will pay off with success. Webb's antenna assembly was deployed a couple hours ago. Apparently, it will allow downloading of at least 28.6 GB of data two times a day.
Click to expand...

I find it all so exciting. As far as the data transmission capability goes, that's probably way more than I manage to wring out of my DSL setup on the average day lately... and that only runs from here to the central office half a mile down the road.
 
AG_PhamD said:
In that the JWST has almost 350 single point failures, and a bunch that are mission critical, I think having a backup would have a good idea. A lot can go wrong between now and deployment. Additionally, with as little as a 6 year lifespan due to the fuel limitations, if the primary program is successful the backup could be used to essentially extend the program as has been done with many space programs. If JWST fails (knock on wood) it’s pretty unlikely we’ll see a second one built.
Click to expand...

Yeah but they must have done the exponential math there. I mean who's to say that having a backup ready to go, sticking in some fix and getting that one off to a perfect launch #2 would not subsequently result in a fail at critical path point #78 instead of at #43?

They had to have done their best with superlative QA and let it rip. If it fails, hope it fails late in the rollout of preparation for usage, so they can know as much as possible about what worked great and what needs work.

I bet they have a short list of hotly debated fail points. If a consensus implementation on one of those argued issues turns out to moot the mission, sure, then there will be recriminations. But we'll still build another space telescope, and other stuff we haven't even figured out we need to invent yet. It's human nature. We can't stop being ourselves, thank goodness. :D:love::LOL::ROFLMAO:
 
Man this was not a good weekend for riding. I usually get off early on Christmas Eve but it was raining and 37 so thats not a fun tandem Christmas light ride. Its not fun commuting in that weather. Well yesterday I guess I had too much sugar and felt too tired to ride. It does not take much to make me feel loopy but I think it was because I didn't to have breakfast before I had that small amount of cashew brittle. But last time I piloted the tandem after too much carbs we crashed so was not going to take any chances. It snowed a bit this morning and was pretty cold. So by afternoon its nice and thawed and we were going to go to a big display lane called peacock lane about 5 miles away. But the temps down to 33 and it's supposed to start snowing. The streets are dry here but I don't know around town. It does not take much for the front to slide on the tandem. I had wanted to change the bar on the tandem. I changed it a bit ago and it was great but just a tad too short when I wear heavy gloves. It was the hump in the center of the bar would not let me move the brake levers in enough. I wanted a straight bar with no angle at all but never found one but this one has little angle. I use duct tape around the bar to thicken it a bit before I use bar tape and trying to remove that the nit is 37 degrees is almost impossible. But got everything changed over ready for the ride that just got canceled. I was going to replace the headlight that came on. The tandem. It was a great light that only lighted the ground nice and wide but it was not bright enough on places with no light and I cracked its mount it was just plastic. So I bought a new light to replace it same as on my commuter. But of course I forgot all my wiring tools to splice the wires. I can only work on the bike on weekends as I don't have light to see it in the evenings.
 
Roller said:
Not to belabor the point, but if the current mission were to fail and there were a backup plan and equipment in place, I'm sure there would be a lengthy investigation to determine how to avert failure the next time, which might involve expensive re-design. Then, too, with so many single points-of-failure, wouldn't there still be considerable risk on a second go-around?

In any case, I'm also enthusiastic about the JWST and hope that all the years of engineering will pay off with success. Webb's antenna assembly was deployed a couple hours ago. Apparently, it will allow downloading of at least 28.6 GB of data two times a day.
Click to expand...

Well, assuming it would be a single component failure, a complete redesign would probably be an extreme possibility. And a redesign of a faulted part would likely cost a lot of time, money, and political arguments, but it would be a lot cheaper than at the best rebuilding a new satellite, and worst having to design an entirely new one. I’m sure NASA wouldn’t be launching without ensuring the lowest chance of failure on these non-redundant mechanisms. And I’m sure the parts at highest risk of problems are those involving the opening the the sunshade, which they presumably only have to get right once.

I think the better argument is that with $10B invested, a fraction of that being the actual cost to build and launch the telescope, building a second telescope to replace JWST when it runs out of fuel in a mere 6-10 seems reasonable. I read an article somewhere that said normally to build a second satellite (at the same time as the first) costs 20-30% as building just one. And that wasn’t with the context of JWST that has had extreme technical and political challenges that only add delay and therefore cost. 6 years for $10B seems like an awful of money for the investment.

That said, it seems NASA tends to underestimate project lifespans, I imagine to prevent political backlash if things go south prematurely, get political brownie points when projects last longer than “expected”, and to help justify new projects on budgets. Famepuslt the Votager spacecraft were “designed” to last 5 years but are going on 44 years. Hubble was designed last 15 years and is still kicking around 30 years later. I doubt we’ll see anything close with Webb, but hopefully 6 years is really a low ball.

Anyways, it’ll be exciting to see what images and discoveries come back.
 
TBL said:
With my last dentist appointment of the year out of the way this morning, I am now obligation-free until January 3rd. :cool: I'll be going up to Tahoe the day after Christmas and staying through New Year's. 😁
Click to expand...
Hey TBL, just thought I would check in on you here. Did you end up going up to Tahoe? Looks like all roads in and out on both 80 and 50 are closed out and people have been trapped there.
 
TBL said:
Postponed :(

Right now the plan is to leave Wednesday. So hopefully that will work out. Can't complain about the snow and rain though--it's been amazing.
Click to expand...
Yeah Tahoe is killing it with snowfall. Really happy for them because it’s my favorite ski destination overall and they have some really lean years there.
 
Edd said:
Yeah Tahoe is killing it with snowfall. Really happy for them because it’s my favorite ski destination overall and they have some really lean years there.
Click to expand...

Snow hogs! 😉 Some of that s/b covering the slopes in the Catskills and Adirondacks. We got bupkis so far.

Today I'm hauling out some pots and pans I haven't used for decades, cleaning them up for sticking on a table at a friend's yard sale next spring with a price that's right, like 25c, just to make sure they don't come back home at day end.
 
Back to work today 😒
Stock taking for the next three days. Normally we are pretty quiet at this time of year. However I notice there are a good number of orders on the system. So with people off it’s going to be a busy three days.
And as I had to cancel my day off today I’m not feeling very happy about it!
 
Apple fanboy said:
Back to work today 😒
Stock taking for the next three days. Normally we are pretty quiet at this time of year. However I notice there are a good number of orders on the system. So with people off it’s going to be a busy three days.
And as I had to cancel my day off today I’m not feeling very happy about it!
Click to expand...

Will you be able to take another day off in lieu of today's cancelled day off?
 
ericwn said:
Finished the last day of work for this year. Have been busy in the evenings building the 1989 Lego Batmobile with my son who’s very excited about it as well.
Click to expand...

Pics when finished :D
 
Back
Top