The James Webb Space Telescope and stuff

[ZooNamedGames]

With it delayed so far- why isn’t SLS a suitable option to launch JWST? It was initially intended to be a SLS payload.

[Ultimate Steve]

37 minutes ago, ZooNamedGames said:

With it delayed so far- why isn’t SLS a suitable option to launch JWST? It was initially intended to be a SLS payload.

With the current schedule there will not be another SLS ready to launch JWST until after 2024 if Artemis stays on schedule.

[ZooNamedGames]

1 hour ago, Ultimate Steve said:

With the current schedule there will not be another SLS ready to launch JWST until after 2024 if Artemis stays on schedule.

If JWST stays on it’s bumpy delayed course that would coincide with a ready SLS for it.

Likely been posted 10000 times already but to further my point.

 

Edited September 12, 2019 by ZooNamedGames

[Ultimate Steve]

8 minutes ago, ZooNamedGames said:

If JWST stays on it’s bumpy delayed course that would coincide with a ready SLS for it.

Likely been posted 10000 times already but to further my point.

 

I'd imagine that delays will get less common towards the end of development. A delay to 2026 at this point would mean a 3.5x schedule slip (2 -> 7 years).

[ZooNamedGames]

2 hours ago, Ultimate Steve said:

I'd imagine that delays will get less common towards the end of development. A delay to 2026 at this point would mean a 3.5x schedule slip (2 -> 7 years).

Never know though. Another rip in testing or damage in shipping or worse- a late flaw discovered after the fact (Hubble’s flaw went so far unnoticed it was actually certified for flight and then launched so this isn’t too far fetched) could all delay it. Of course, as much as I’d like to see it fly SLS- I’m rooting for it to fly period- sooner the better- no matter the launch vehicle.

[tater]

 

7 hours ago, ZooNamedGames said:

Of course, as much as I’d like to see it fly SLS- I’m rooting for it to fly period- sooner the better- no matter the launch vehicle.

JWST is flying on Ariane 5. It was never supposed to fly on SLS, part of the ESA participation has been the launch from the start.

[Ultimate Steve]

Why switch? Ariane 5 is perfectly capable of launching jwst, costs less than SLS, and has an excellent reliability record, something SLS will not be able to prove it has for a while. Plus, it frees up an SLS for a mission that needs it.

If it gets delayed for longer than Ariane 5 will be around, I'd imagine you would have several other capable vehicles to choose from by that point (although probably not too proven). Ariane 6, NG, and Vulcan should be around and flying by 2022-3. I don't think fh has a big enough fairing.

[tater]

23 minutes ago, Ultimate Steve said:

Why switch? Ariane 5 is perfectly capable of launching jwst, costs less than SLS, and has an excellent reliability record, something SLS will not be able to prove it has for a while. Plus, it frees up an SLS for a mission that needs it.

If it gets delayed for longer than Ariane 5 will be around, I'd imagine you would have several other capable vehicles to choose from by that point (although probably not too proven). Ariane 6, NG, and Vulcan should be around and flying by 2022-3. I don't think fh has a big enough fairing.

SLS was never even considered for JWST as far as I know.

 

[ZooNamedGames]

On 9/12/2019 at 10:11 AM, tater said:

SLS was never even considered for JWST as far as I know.

 

Only reason I mentioned it was because I oddly recall that being the case like 4-5 years ago. Maybe I was wrong though. I'm feeling like the Mandela Effect is screwing with me. 

[tater]

 

[jadebenn]

On 9/11/2019 at 7:35 PM, ZooNamedGames said:

With it delayed so far- why isn’t SLS a suitable option to launch JWST? It was initially intended to be a SLS payload.

There is absolutely no reason to launch JWST on SLS, and this is coming from one of the biggest SLS fanboys on this forum. In fact, there'd be a lot of risk inherent in launching on SLS (because the spacecraft was not designed around it) for no practical benefit - it's not like it'd be able to take advantage of the greater payload.

I'm sure if the designers of JWST had known that there'd be an SHLV just about ready by the time their payload was wrapping-up that they would've considered it, but when JWST started super-heavy lift was both not-at-all assured and very far-off into the future.

It's the future designs, like LUVOIR, that will be taking advantage of the SLS and using its capabilities to enable science. It's way too late to try and change the JWST.

[tater]

 

[GearsNSuch]

10 minutes ago, tater said:

Maybe they should just say something when the costs and deadline haven't increased.

Edited January 28, 2020 by GearsNSuch

[Wjolcz]

I honestly start thinking it would've been cheaper and faster to build a dedicated non-reusable BFR-like rocket and put a solid, one piece mirror on that thing as the payload.

Edited January 28, 2020 by Wjolcz

[ThatGuyWithALongUsername]

On 1/28/2020 at 6:32 PM, Wjolcz said:

cheaper and faster ... dedicated non-reusable BFR-like rocket 

"Cheaper and faster..." I'm not so sure about that

Spoiler

 

[Silavite]

On 1/28/2020 at 3:19 PM, GearsNSuch said:

Maybe they should just say something when the costs and deadline haven't increased.

Ayup. They're saying that it should be ready before the end of 2021 (for now).

https://arstechnica.com/science/2020/06/james-webb-space-telescope-will-absolutely-not-launch-in-march/

Edited June 10, 2020 by Silavite

[Hannu2]

On 1/29/2020 at 1:32 AM, Wjolcz said:

I honestly start thinking it would've been cheaper and faster to build a dedicated non-reusable BFR-like rocket and put a solid, one piece mirror on that thing as the payload.

When they began to plan JWST, they had no idea that such rockets would be available in next decades. It would have been impossible with NASA way, from which SLS is perfect example. It is typical that flagship probes take more than a decade to build and they are obsolete from hindsight perspective when they are finally launched.

[Gargamel]

Got to talking to a coworker today about the JWST.  Not sure how we got onto the subject, but I explained how the JWST would be able to see farther into the past due to the light being redhshifted due to the expansion of the universe, etc etc.  Had to simplify it some, as they were even unaware that distance = time in this regard, and that we were seeing things as they once were, on time scales not really comprehensible to human mind.   So this led to type 1a Supernovas, Hubble, and eventually coming to the heat death of the Universe.

It then occurred to me that it's about even money that Heath Death just might happen before we get to see JWST launched. 

[wumpus]

On 1/31/2020 at 7:31 PM, ThatGuyWithALongUsername said:

"Cheaper and faster..." I'm not so sure about that

  Reveal hidden contents

 

Atkin's laws of rocket design:

39. Any exploration program which "just happens" to include a new launch vehicle is, de facto, a launch vehicle program.

https://spacecraft.ssl.umd.edu/akins_laws.html

Making it a launch vehicle program simply gives it more ways to delay, and makes it that much easier for the Senate to take over the program.  Also, the thing has consumed the lion's share of NASA's non-SLS budget.  Do you really want to risk it on the maiden voyage of some "cheaper and faster" booster?  There's a reason that SpaceX launched a wheel of cheese and Elon's old Tesla on the first flight.

[linuxgurugamer]

1 hour ago, wumpus said:

Atkin's laws of rocket design:

39. Any exploration program which "just happens" to include a new launch vehicle is, de facto, a launch vehicle program.

https://spacecraft.ssl.umd.edu/akins_laws.html

Making it a launch vehicle program simply gives it more ways to delay, and makes it that much easier for the Senate to take over the program.  Also, the thing has consumed the lion's share of NASA's non-SLS budget.  Do you really want to risk it on the maiden voyage of some "cheaper and faster" booster?  There's a reason that SpaceX launched a wheel of cheese and Elon's old Tesla on the first flight.

Thank you for the link.  It's great, and I'll probably discuss the during one of my next streams

[JoeSchmuckatelli]

Aside from the covid delay - is there a reason for such a long lead time to launch? 

 

Given that they're going to put it in L2 orbit, there isn't a 'launch window' like there would be for Mars etc. 

 

So if the telescope is ready - why not build a rocket and go? 

[Gargamel]

1 hour ago, JoeSchmuckatelli said:

Aside from the covid delay - is there a reason for such a long lead time to launch? 

 

Given that they're going to put it in L2 orbit, there isn't a 'launch window' like there would be for Mars etc. 

 

So if the telescope is ready - why not build a rocket and go? 

They're making sure it's ready.  As a deployable, it's probably the most complicated automated spacecraft ever made.    Look at all the missions that have gone up and had to deal with failed deployments of dishes or solar panels.   Where this one is going, it's either it works perfectly, or it's junk.  There's no practical hope for a repair mission, like they did with hubble, and if the heat shield doesn't deploy, the camera won't work. 

[tater]

 

[RCgothic]

It's a 7 month delay:

 

[JoeSchmuckatelli]

Is there a reason why they can't get the telescope deployed and operating in LEO (to be close enough to work on if need be) ... And then later boost it to the Lagrange point for its mission? 

 

Edit - we really need a functioning space truck! 

Edited July 18, 2020 by JoeSchmuckatelli