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Tangent / maybe unrelated / maybe not notable, but. I actually found something quite funny about ML-1... Look here, PDF page 34-36 / in-document page numbers 29-31: the program plans to incorporate lessons learned from developing the first Mobile Launcher into the acquisition approach for a second Mobile Launcher ... developing and maintaining a three-dimensional (3D) model to facilitate integrated design and then We have also found that the U.S. Navy and the commercial shipbuilding industry use 3D product models as tools to document design stability.27We found that there are aspects of shipbuilding that are analogous to building a Mobile Launcher in that both involve designing and building a large metal structure and installing multiple complex integrated systems to support complex functions such as launching spacecraft, or in the case of the Navy, launching aircraft and/or missile systems. NASA officials agreed that developing a Mobile Launcher is analogous to shipbuilding. Best practices for commercial shipbuilding indicate that 3D product models documenting 100 percent of the system’s basic and functional designs should be complete before construction begins. • Basic design includes fixing the ship steel structure; routing all major distributive systems, including electricity, water, and other utilities; and ensuring the ship will meet the performance specifications. • Functional design includes providing further iteration of the basic design, providing information on the exact position of piping and other outfitting in each block, and completing a 3D product model. The combined basic and functional designs in conjunction with the 3D product model provide the shipbuilder a clear understanding of the ship structure as well as how every system is set up and routed throughout the ship. This detailed knowledge allows commercial ship builders to design, build, and deliver complex ships such as floating production storage and offloading vessels, which are able to collect, process, and store oil from undersea oil fields, within schedule estimates. The improved design processes the EGS program is pursuing in the development of the second Mobile Launcher, including the development of a 3D model to facilitate integrated design, have the potential to improve program outcomes. Further, achieving design stability before beginning construction would also improve this potential.
I'm not sure where it might fit best. Maybe On top of this, the costs to assemble, integrate, prepare and launch the SLS and its payloads are funded separately under Exploration Ground Systems (EGS),[97] currently about US$600 million[98] per year. EGS bears costs such as modifying the launch pads and platforms at LC-39B to support SLS variants. Somewhere around there? Leijurv (talk) 21:25, 16 September 2020 (UTC)
Funding history section
Thanks so much to the editors who have worked to create a clear section on the large amount of public funding that has gone into the development of this heavy launch vehicle over its 11 year history to date! This is exactly what encyclopedias can, and should, do well! ... and is not easy to cover thoroughly, including how the optimistic estimates meet with actual reality in these sorts of government cost-plus funded procurement and development contracts, in tradition media articles that cover the space.
This well-sourced article section on Wikipedia is now the go to place for an accurate summary of rocket development funding for SLS. N2e (talk) 02:13, 18 January 2021 (UTC)
Rewrite of paragraph in funding history
I'd like to rewrite this bit:
There are no current NASA estimates for the average costs per flight of SLS, nor for the SLS program recurring yearly costs once operational. In 2016, the projected annual cost for Orion, SLS, and ground systems was US$2 billion or less.[102] NASA associate administrator William H. Gerstenmaier has said that per flight cost estimates will not be provided by NASA.[103] In May 2019, NASA's Office of Audits reported that the SLS Block 1's marginal cost per launch is to be at least US$876 million.[104] By comparison, a Saturn V launch cost roughly $1.23 billion in 2016 dollars.[105][106] A letter from the White House to the Senate Appropriations Committee revealed that the SLS's cost per launch is estimated at "over US$2 billion" after development.[107] NASA did not deny this cost and an agency spokesperson stated it "is working to bring down the cost of a single SLS launch in a given year as the agency continues negotiations with Boeing on the long-term production contract and efforts to finalize contracts and costs for other elements of the rocket".[108]
I talked about this way back in July (#Coverage of Cost in the Article Itself) but it's probably time to get back to it for real. I'd like to add some analysis (sourced analysis; don't worry) on what's really going on - why there are wildly different numbers from different sources.
I plan to use Space_Shuttle#Budget as a model, because it's a featured article, and because that paragraph actually makes cohesive sense, and isn't just a list of people that disagree with each other on how much the Space Shuttle costs.
Here's a first stab at it (only put in a few sources, will add more after some editing):
There are no NASA estimates for how much SLS will cost per launch, nor for the SLS program recurring yearly costs once operational. Cost per launch is not a straightforward figure to estimate as it depends heavily on how many launches occur per year. For example, similarly, the Space Shuttle would have cost $576 million per launch at 7 launches per year, but the cost of adding a single additional launch in a given year was determined to be just $252 million of marginal cost. However, at the rate that it actually flew, the cost in the end was $1.64 billion per Space Shuttle launch, including development.[1]: III−490
NASA associate administrator William H. Gerstenmaier has said that there will be no official per flight cost estimates of any variety provided by NASA for SLS.[2]
Several internal NASA programs and project concept study reports have released proposed budgets that include future SLS launches. For example, a concept study report for a space telescope that would launch in 2035 was advised by NASA HQ in 2019 to budget $500 million for an SLS launch.[3] Another study also proposing a space telescope, also scheduled for a "mid-2030s" launch, budgeted $650 million for their launch.[4]
Europa Clipper is a scientific mission that was required by Congress to launch on the SLS. Oversight bodies both internal and external to NASA disagreed with this requirement. First, NASA's Inspector General office published a report in May 2019 about this requirement.[5][6] It said that Europa Clipper would need to give up $876 million for the "marginal cost" of its SLS launch. Then, an addendum to the letter, published in August 2019, increased this estimate and stated that switching to a commercial rocket would actually save over $1 billion, although this savings may have included a portion of costs related to the delay in launch schedule. A JCL analysis cited in that letter put the cost savings at $700 million, with SLS at $1.05 billion and the alternative at $350 million.[7][8] Finally, a letter from the White House Office of Management and Budget to the Senate Appropriations Committee revealed in October 2019 that the SLS's total cost to the taxpayer per launch is estimated at "over US$2 billion" after development is complete (program development has cost $20 billion to date in 2020 dollars). The letter urged Congress to remove this requirement, in agreement with the NASA Inspector General, adding that using a commercial launch vehicle for Europa Clipper instead of SLS would save $1.5 billion overall.
NASA did not deny this $2 billion cost of launch and an agency spokesperson stated it "is working to bring down the cost of a single SLS launch in a given year as the agency continues negotiations with Boeing on the long-term production contract and efforts to finalize contracts and costs for other elements of the rocket". This White House figure depended on the rate of construction, so building more SLS rockets faster would decrease the per-unit cost[9] (for example, Exploration Ground Systems (whose only role is to support, assemble, integrate, and launch SLS) has separately budgeted fixed costs of $600 million per year on facilities, spread across however many rockets launch that year). Jim Bridenstine then shared informally that he disagrees with the $2B figure since the marginal cost of an SLS launch should decrease after the first few, and is expected to end up around $800M to $900M, though negotiations were only just beginning for the later cores.[10]
References
^Jenkins, Dennis R. (2016). Space Shuttle: Developing an Icon – 1972–2013. Specialty Press. ISBN978-1-58007-249-6.
^"I do not agree with the $2B number, it is far less than that. I would also say that the number comes way down when you buy more than one or two. And so I think at the end we're going to be in the $800M to $900M range - I don't know, honestly. We've recently just begun negotiations on what number three through whatever - we don't have to buy any quite frankly, but we intend to. But we're looking at what we could negotiate to get the best price for the American taxpayper, which is my obligation as the head of NASA."
There's a first pass at it. I erred on the side of including too much rather than too little. Perhaps the two internal studies are too unreliable to cite even descriptively like that. Perhaps we don't need the entire story of the Europa Clipper cost estimates. But for better or for worse, I managed to include every source that was originally in the infobox and added explanations for each. Also, in the case of any contradiction between what I say now and what I said back in July, I defer to my past self, because I'm just skimming now things I read in depth & wrote back then lol
I don't think There are no NASA estimates for how much SLS will cost per launch, nor for the SLS program recurring yearly costs once operational. is true. I think it'd be more accurate to say: There are multiple, conflicting NASA estimates for how much SLS will cost per launch and for SLS program recurring yearly costs.
If we're presenting the information this way, I would also not use the term "marginal cost" when referencing the Clipper report, unless it's stated in the context that this is a reasonable assumption based on the context of the figure. Otherwise it gives the impression the report itself says that when the reality is a bit... unclear.
I don't think ... is true Well it's currently written in the article (There are no current NASA estimates for the average costs per flight of SLS, nor for the SLS program recurring yearly costs once operational.) I thought the problem was that all the numbers we have are indirect NASA estimates, nothing in any official capacity and nothing from the actual "SLS team". As in, they are not claiming any specific cost publicly as "The Cost", and Gersteinmaier said that they won't ever. Perhaps it would make more sense as "There are no current official NASA estimates"? In the context of what I wrote up there, I think replacing the Saturn V comparison with a Space Shuttle comparison is better (and more honest tbh) because the Space Shuttle has a clear example of the cost of adding one more launch in a given year (0.25 billion) versus the actual cost of launch in the end (1.6 billion) being two very different figures so it will help the reader understand why there are such different numbers being thrown around by different parties. If we add the context that NASA is not committing to Any Specific Number then I think that will help hold the reader's hand through why the next few paragraphs are so wacky.
Otherwise it gives the impression the report itself says that It does though, see here document page 18 / PDF page 24, second paragraph: NASA officials estimate the third SLS Block 1 launch vehicle’s marginal cost will beat least $876 million while commercial launch vehicle costs are estimated to be approximately $450 million (see Table 3). So I think this does make sense. Leijurv (talk) 22:08, 18 January 2021 (UTC)
Given that the first issue is already in the article and just needs tweaked wording, and the second is a direct quote from the source, I might just add this to the article and then it could be tweaked further in main space? Leijurv (talk) 00:14, 20 January 2021 (UTC)
Added to main article here, with a few tweaks to wording to make it more clear what's going on, and a whole lot of citation fixes. Leijurv (talk) 21:37, 20 January 2021 (UTC)
Great. I can see a few tweaks, and the need for citations, but overall, is a good attempt at improving the Wikipedia explication of an important and notable topic. I'll take a look at it in the article space. N2e (talk) 18:28, 21 January 2021 (UTC)
@N2e: About the two remaining clarification tags, I'm not really sure how to address them: {{clarify|was the "study" advised by NASA to do ...? or did the "study" just point out that some group was advised by NASA to ...? }} and {{clarify|does the study show what sort of estimates on annual flight rate NASA was assuming in providing those per flight numbers to a potential payload user?}} The citation has the quote right there. It's just "The launch cost ($500M for the SLS launch vehicle, as advised by NASA Headquarters) is also included." on page 281. That's all the information there; they say they were advised and that that's the cost. I'm not sure what else I could say. Leijurv (talk) 18:56, 21 January 2021 (UTC)
"first two flights"
@2603:7080:1b07:97ac:e102:e997:501:3be0: Regarding edits [2] and [3]. First, please follow WP:BRD, second, see my edit summary in the first revert ([4]) revert ip edit: cited sources do not indicate this applies to only the first few, see the RfC on the talk page for this exact figure. If you look at from #RfC for SLS Launch Cost to this section you can see there has been tens of thousands of words of discussion on this particular infobox entry. Also see the section of the main article Space Launch System#Per launch costs. The cited reliable sources do not say that that figure only applies to the first two. For example, we have the Bridenstine source saying that I would also say that the number comes way down when you buy more than one or two. And so I think at the end we're going to be, you know, in the US$800 million to US$900 million range - I don't know, honestly but this is offhand, non-independent, unofficial/informal, etc. Bridenstine has every obligation to make the cost lower, and to make the cost seem lower. He is also no longer the head of NASA. We need to be careful of WP:CRYSTALBALL here, and we should not treat speculation of future contract negotations as anything but speculation. Please follow WP:BRD and do not reinstate the edit, if you still want to make it please discuss here what sources you have to support the claim, otherwise it is WP:OR. Leijurv (talk) 20:22, 30 March 2021 (UTC)
Detail here versus artemis
@StarshipSLS: What do you think about maybe putting your table in Artemis 1 instead? I feel like that article is the place to go into detail about this specific booster, while this article is more for general information about the rocket. And I'm not just referring to the table but also to some or all of the paragraph right before it. Leijurv (talk) 18:49, 26 May 2021 (UTC)
"world's highest-ever total thrust at launch" disputed
First of all, The N1 (rocket) had a significantly higher thrust at liftoff with a total of 45,150 kN compared to SLS's 39,440ish kN
Second, the 5-segment booster's listed thrust seems(?) wrong. The best citation I could find for it (an Orbital ATK fact sheet from December 2017) says the booster has a maximum thrust (which I would think means Vacuum) of 3,600,000 lbf (16,000 kN). The 4-segment SRBs used for the shuttle had a 2,700 kN difference between their Sea Level thrust of 12,000 kN and their vacuum thrust of 14,700 kN. If the SLS SRBs have a similar thrust downgrade (down to ~13,300,000 kN but I cannot find a good source for their sea level thrust), then the Sea Level Thrust of Boosters+Core would be 34,040 kN. This is less than the sea level thrust of Energia, 34,800 kN. This would give the SLS Block 1/1B the 3rd highest-ever total thrust at liftoff for all flown rockets, or 2nd highest for rockets that successfully delivered payloads to orbit.
Of course, NASA may have simply forgotten about Energia and the N1 when they claim it is the most powerful rocket (it certainly has the highest thrust of any American Rocket or Rocket currently(ish) flying). Or they may already be thinking about Block 2, whose boosters may surpass the Energia or even (though Unlikely) the N1.The.dad.drew (talk) 23:55, 19 September 2020 (UTC)
@The.dad.drew: I think you're working off a bad assumption in regards to SRB thrust ASL being lower than thrust in vacuum. Everything I've seen suggests the opposite is true.
The N1 is probably being excluded due to the lack of successful launches. Kinda like how the old 4-segment SRBs aren't the most powerful SRBs ever built, just the most powerful to actually fly. – Jadebenn (talk·contribs·subpages) 02:10, 27 September 2020 (UTC)
@Jadebenn: For one thing, no, all rocket engines produce a lower thrust at sea level than in vacuum, you literally have to subtract off ambient pressure as one of the terms of the rocket thrust equation. But I have found a good source for the thrust of the SLS 5-segment SRBs, a NASA Technical report about the SLS Booster Development. 3.6 Million lbf is indeed its vacuum thrust, with a Sea Level thrust of 3.28 Million lbf. This is marginally more powerful than the Energia, and so I will concede that the SLS will be the most powerful rocket to successfully deliver payload to orbit. The.dad.drew (talk) 18:56, 1 October 2020 (UTC)
I'm confused. It appears that NASA is saying that the SLS Block 2 will have a higher total payload to LEO than any rocket ever built up to the time of the claim in 2017. That's all well and good, but the first launch is Block 1 and it hasn't happened yet, Block 1 is less capable than Saturn V, Block 2 won't launch until after 2024, and SpaceX Starship is supposed to launch at about the same time as Artemis 1. This means that there is a very high probability that SLS will never have the "highest-ever total payload to LEO" as (sort of) implied in the lede. I think we should just remove the statement from the lede completely, as it will be too hard to replace it with something that is both truthful and concise. A discussion of the nuances could be added later in the article, probably in the "criticisms" section. -Arch dude (talk) 04:13, 11 August 2021 (UTC)
I simplified the statement by just comparing to Saturn V and removing "highest-ever". Feel free to add a new comparison section later in the article.-Arch dude (talk) 18:21, 12 August 2021 (UTC)
Can you clarify where in the MOS you are referring to, regarding these changes? When I look at MOS:UNITS I see In non-scientific articles with strong ties to the United States, the primary units are US customary (pounds, miles, feet, inches, etc.) This article is, however, fairly plainly a scientific article. However, later on, it says or such other units as are conventional in reliable-source discussions of the article topic. Related to this idea of matching the source, the next bullet point:
I would prefer if we stuck with the cited numbers (e.g. 101,400 lbs), but used the convert template to display to the reader something in the desired units. Is this possible using that template? The reason is that while WP:CALC does exist, and it is allowed for you to do these conversions manually yourself, it is still better (per WP:V) if the number directly matches the cited source in both quantity and unit.
For example: you changed {{cvt|101400|lbs}} to {{cvt| 46| t| lb}}. This changed the visual outcome to the reader from Block 2 Cargo: > 101,400 lb (46,000 kg) to Block 2 Cargo: > 46 t (101,000 lb). The cited source says SLS Block 2 will be designed to lift more than 46 t (101,400 lbs.) to deep space. Perhaps we should instead have {{cvt|101400|lbs|t|0}} which renders visually as 101,400 lb (46 t)? I would prefer that since then both numbers match the source, both 101400 and 46, as opposed to 46 matching the source, and 101000 not matching 101400.
To maintain a consistency between numerous launch vehicles, we need a standard template, but of course to include Metric as well as Imperial to make it readable to both the parties
In both the cited source you mentioned (nasa.gov) pages, they had given Metric unit tonne in primary and given lb in bracket, so I don't think there is any confusion there
But to your point, as we are losing on the specifics, I will modify the convert template to feed in the accurate decimal value for tonne in primary unit, which will resolve to specific lb
I think simpler approach is to use {{Cvt}} with order=flip which will retain the original value as well as change the primary unit to Metric according to MOS Chandraprakash (talk) 20:23, 23 June 2021 (UTC)
Proof for Citation reference nasa.gov using Metric as primary unit.
@Frozenprakash: Whoa, you shouldn't upload images like that. While you can upload it in this case due to commons:Template:PD-NASA, you certainly shouldn't have marked it as "own work" or set your own copyright license. I would recommend marking them with commons:COM:GCSD#G7.
Sounds good, makes sense to have the more accurate figure with |0 and order=flip as needed. I still see a number of changes though when I compare the revisions: [5]. What is the reason for those? For example, I picked a random one: there's | length = {{cvt|177|ft|m}} which was changed to 54 meters. This is wrong for the same reason; the cited source says 177 feet. So it should convert from 177 feet into meters, instead of the other way around. If you want to flip the order per MOS, just add the order flip option, don't change the source unit. It seems to me like all of these changes should be reverted to the original values, but with a few units changed or order=flip added... Or is there something I'm missing? Leijurv (talk) 00:08, 24 June 2021 (UTC)
Checking back in @Frozenprakash:, are you down to make those changes? I don't particularly want to sort through all the edits you made and the newer ones since then updating unit figures. But I see you did not edit since June 23 and you say you were going to make an update ^ on June 27. I believe the issue is mostly still present, even though some other editors have updated some of the figures?
Also you really should mark those two Commons screenshots for deletion. They are copyright violations because they are not your own work, they are screenshots from NASA's website. It has been more than a week so my earlier suggestion to mark them as commons:COM:GCSD#G7 is no longer on the table. You should clear up the copyright status by correcting it away from "Own work", which it isn't, and determining whether the images are allowed on commons. If they are actually free images, mark them as such (something valid other than "own work"), and if they are not, mark them as commons:COM:CSD#F1 (or I will soon). Leijurv (talk) 22:46, 12 August 2021 (UTC)
Planned timeline?
I think this article needs some sort of description of NASA's future development and launch timeline. The article does not appear to discuss when the first Block 1B will launch or when the first Block 2 will launch. This is particularly important (to me, at least) to a reader's understanding of the the capabilities of the system compared to other systems like the Saturn V. I added the 2029 date for Block 2 to the lede, but my reference, while reliable, is a bit vague. -Arch dude (talk) 05:46, 13 August 2021 (UTC)
Artemis 3 is 2024, and there are only three ICPS missions, meaning EUS (so block 1B) will start after that, making it no earlier than 2025. Specific sources are hard to come by but here is one for EUS still being in testing phase in 2024. Also this one that I just cited says that BOLE test firings will begin in 2024. Leijurv (talk) 06:35, 13 August 2021 (UTC)
Also from the second page of this there is this image and it says Credit: NASA and it says it's from a NASA presentation but I can't quite find which one. It might be a good infographic to add or page to cite. Leijurv (talk) 06:37, 13 August 2021 (UTC)
Thanks! I will tighten up the Artemis paragraph in the lede and consolidate the dates for the blocks, making the lede shorter and (I hope) more coherent. -Arch dude (talk) 22:11, 13 August 2021 (UTC)
I use old-fashioned wikitext editing. Editing the lede was almost impossible because the citation templates were so long. Therefore, I have moved the citation text into the reflist. This has no visual effect on the article. See WP:LDR. Does this cause any problems for folks using the visual editor? I will now start actual copyediting of the readable text. -Arch dude (talk) 18:48, 14 August 2021 (UTC)
That's cool I wasn't aware of that. I also do wikitext editing and when there's a ton of references I use a ton of "show preview" and ctrl+f for certain phrases. Perhaps I will use list defined references in the future :) Leijurv (talk) 21:39, 14 August 2021 (UTC)
New lede
I think I retained all of the information that was in the old lede, and I added the planned first launch dates. I now need to make sure I have the correct references connected to the correct facts in the lede. This will be tedious. I did remove four refs temporarily, but I will add them back if we still need them, so I'm storing them here. I strongly suspect that some of the older refs should be removed, as they are superseded.
Here are the refs I temporarily removed:
[1][2][3][4]
I think it is a little oversimplified to call it just three phases (1 1B 2). There are many subvariants. For example, the RL10 engine in the ICPS will be changed from the B-2 variant (perhaps) to the C-2 variant between Artemis 1 and Artemis 2 (yet still remaining at one engine). Additionally, the main engine switch from RS-25D to RS-25E will increase thrust (and supposedly decrease cost even though that is highly questionable), but it isn't actually given a label. (in my personal opinion it might make sense to call the RS-25E variant "Block 1C" but that's just my opinion there are no sources that actually do that). Also from the third to the fourth launch, the RL10 C-2 will be swapped to RL10 C-3 and increased in quantity from one to four (per Exploration Upper Stage). Additionally, at some point within Block 2, the RS-25E contract will end and will be replaced with RS-25F which has additional improvements and a couple percent more thrust.
Anyway all that being said I think the lede might want to make some mention of how there are many subvariants in each block, I don't really know how to phrase it right, but I think it's important to call out that nearly every rocket will unique and there are constant changes even within each block. Even though Congress put out certain requirements for each, might be good to mention that it isn't all the same rocket in each block.
Glad you like it. I'll add something brief, but this is the lede: details belong in the body of the article. Can you work on it? -Arch dude (talk) 01:57, 15 August 2021 (UTC)
Special:Diff/1038835975 This is good 👍 Those details are sprinkled throughout. I also do not have a WP:RS on the specific RL10 variants, those are rumors / indirect leaks / insider info. NASA has changed their plans so many times on this that there are a lot of conflicting sources :( For example, this sentence of the main article However, this competition was planned for a development plan in which Block 1A would be followed by Block 2A, with upgraded boosters. NASA canceled Block 1A and the planned competition in April 2014. seems simple but it took a lot of research to understand exactly what happened, and why the sources pre/post that time wildly conflicted with each other. Just yesterday I realized the plans for BOLE were wrong and fixed those too. Leijurv (talk) 02:38, 15 August 2021 (UTC)
@Fcrary: The reference I cited supports that SLS will transition from RS-25D to RS-25E (so, an increase in thrust) in the middle of Block 1B. But whatever that detail is already in the article body so it doesn't particularly need to be in the lede if you really feel strongly against it. Leijurv (talk) 19:34, 15 August 2021 (UTC)
Are we talking about the same reference? It looks like the one connected to the edit I reverted was a NASA press release from 2017, talking about things like the "first flight test of SLS with Orion in 2018". It doesn't mention anything about upgrades within a SLS block. So I don't see that as a relevant reference. And if the article is going to make a point about upgrades within a SLS block, in the lead, I think we should limit it to significant upgrades. You wrote, above, that "the RS-25E contract will end and will be replaced with RS-25F which has additional improvements and a couple percent more thrust." A couple percent increase in thrust does not sound like a significant upgrade. Fcrary (talk) 01:39, 16 August 2021 (UTC)
if the article is going to make a point about upgrades within a SLS block, in the lead, I think we should limit it to significant upgrades ... A couple percent increase in thrust does not sound like a significant upgrade Fair enough. I don't feel strongly about that.
As I said above, I have had trouble pinning this down as plans have changed a lot, and all of this is hypothetical. None of these rockets have flown :) Leijurv (talk) 06:04, 16 August 2021 (UTC)
Those eight references are all in the loooong sentence at the end of the history section that has all of the dates in the text. I left them in as a less brutal way of saying "about one announced slip per year, thus doubling the development time".-Arch dude (talk) 01:54, 15 August 2021 (UTC)
Yeah I understood where they came from, I'm just not sure I would do it that way. The first one in particular, that the initial date was 2016, was contentious about a year ago, see User_talk:Leijurv#Space_Launch_System. I agree in spirit that the delays are comically long and expensive and that should be conveyed, so I don't feel strongly enough to remove any cites myself though... but I wouldn't be surprised if someone else did so while pointing to WP:CITEKILL :) Leijurv (talk) 02:38, 15 August 2021 (UTC)
What we really need is a single citation to a reliable source article whose subject is the woes of the SLS. Maybe someone will write that some day in some liberal or conservative magazine that likes to bemoan "government waste". -Arch dude (talk) 05:18, 15 August 2021 (UTC)
The closest thing that we have is the series of articles written by Eric Berger in Ars Technica :) (many are already cited) Leijurv (talk) 00:08, 16 August 2021 (UTC)
Hello, I have taken a look at this article for a while, and here're the things that can be improved:
Captions must be succulent. NASA moved out US$889 million of costs relating to SLS boosters, but did not update the SLS budget to match, a March 2020 Inspector General report found. This kept the budget overrun to 15% by FY 2019. At 30%, NASA would have to notify Congress and stop funding unless Congress reapproves and provides additional funding. The Inspector General report found that were it not for this "masking" of cost, the overrun would be 33% by FY 2019. The GAO separately stated "NASA's current approach for reporting cost growth misrepresents the cost performance of the program". is just way too long. The maximum length is about 3-4 lines of text, and no more.
Lead should be shorter. It should be from 2-3 paragraphs and be capitating to the reader.
70 t (69 long tons; 77 short tons) should be converted to 70 metric/imperial ton (... lb) since practically no one use long and short tons, and ambiguous. (imperial or metric?)
Block 1: Core stage, 5-segment SRBs, ICPS 2nd stage. [...] should be converted to prose, and remove bolding.
Replace / for or.
If possible, convert lists to prose, such as Costs of payloads for the SLS (such as Orion crew capsule) [...]
Be specfic. [...] an alternative to be designed and fabricated by the company, but it was rejected by NASA in November 2019 on multiple grounds. What alternative? Why is it rejected?
Check the article for redundant dashes. 140- to 150-tonne should be 140 to 150 (metric/imperial) ton. This unit would also benefit from {{cvt}} template as well.
This is way too tiring to read: The intended uncrewed first flight of SLS has slipped multiple times: originally from late 2016 to October 2017, then to November 2018, then to 2019, then to June 2020, then to April 2021, then to November 2021, and then to some time between January 2022 and March 2022. It should be simplified, and consider worth including. The intended uncrewed first flight of SLS has slipped multiple times: late 2016, October 2017, November 2018, 2019, June 2020, April 2021, November 2021, and then to some time between January 2022 and March 2022. and The intended uncrewed first flight of SLS has slipped multiple times, and as of October 2021 the launch date is between January 2022 and March 2022. is a good alternative in my opinion.
Regarding the first one, I've made that edit here: Special:Diff/1048452526. (btw "succinct" is not quite the same as "succulent" but captions should be both). Regarding units see #Units, it was messed up some months ago and I have not gotten around to fixing (I hoped the other editor would). Regarding the slips, Arch dude moved them into a refnote, perhaps the same could be done? Or maybe that was just to save space in the lead. @Arch dude: thoughts? Leijurv (talk) 02:35, 6 October 2021 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
Captions must be succulent. NASA moved out US$889 million of costs relating to SLS boosters, but did not update the SLS budget to match, a March 2020 Inspector General report found. This kept the budget overrun to 15% by FY 2019. At 30%, NASA would have to notify Congress and stop funding unless Congress reapproves and provides additional funding. The Inspector General report found that were it not for this "masking" of cost, the overrun would be 33% by FY 2019. The GAO separately stated "NASA's current approach for reporting cost growth misrepresents the cost performance of the program". is just way too long. The maximum length is about 3-4 lines of text, and no more.
70 t (69 long tons; 77 short tons) should be converted to 70 metric/imperial ton (... lb) since practically no one use long and short tons, and ambiguous. (imperial or metric?)
Be specfic. [...] an alternative to be designed and fabricated by the company, but it was rejected by NASA in November 2019 on multiple grounds. What alternative? Why is it rejected?
I'm confused by this one. For SLS payloads, Orion is the only one that we know of. NASA might launch further payloads on SLS in the future, but currently, the only planned ones are Artemis 1 through 3 which are Orion. (all that is said elsewhere in the article). So I'm not sure how that could be more specific. And for the second one, Strikethrough because I simply misunderstood where one suggestion ended and the next began, oops What alternative? Why is it rejected?, look at the next sentence of the article rejected by NASA in November 2019 on multiple grounds. These included lower performance compared to the existing EUS design, unsuitability of the proposal to current ground infrastructure, and unacceptable acceleration in regards to Orion components.. This is a summary of the secondary source [6] which goes into more specifics, such as instead of unsuitability of the proposal to current ground infrastructure it actually says the total height of the SLS rocket's core stage with Blue Origin's upper stage exceeds the height of the Vertical Assembly Building's door, resulting in "modifications to the VAB building height and substantial cost and schedule delays.". If it doesn't fit in the VAB that's a big issue. I will edit the two sentences so that they flow better and make more sense. Leijurv (talk) 02:57, 6 October 2021 (UTC)
Check the article for redundant dashes. 140- to 150-tonne should be 140 to 150 (metric/imperial) ton. This unit would also benefit from {{cvt}} template as well.
This is way too tiring to read: The intended uncrewed first flight of SLS has slipped multiple times: originally from late 2016 to October 2017, then to November 2018, then to 2019, then to June 2020, then to April 2021, then to November 2021, and then to some time between January 2022 and March 2022. It should be simplified, and consider worth including. The intended uncrewed first flight of SLS has slipped multiple times: late 2016, October 2017, November 2018, 2019, June 2020, April 2021, November 2021, and then to some time between January 2022 and March 2022. and The intended uncrewed first flight of SLS has slipped multiple times, and as of October 2021 the launch date is between January 2022 and March 2022. is a good alternative in my opinion.
Resilience section should be merged. Lone sentences should be merged as well. The level 3 sections (2.3.1.) should be deleted, as it is way too overkill. Merge the subject to a paragraph.
Infographic from the March 2020 Inspector General report, demonstrating how NASA used accounting to "mask" a cost increase by moving US$889M of boosters from SLS to another cost center, while neglecting to update the SLS budget to match. is way way too POV pushing.
A lot of sentences have an unnecessary details, such as Ars Technica, in an article published on the same day, highlighted that over the entire RS-25 contract the price of each engine works out to US$146 million and that the total price for the four expendable engines used in each SLS launch will be more than US$580 million.
In my opinion, a lot of acronyms can be expanded, such as TLI for trans-lunar injection.
Done Too many diffs to link because I hit save on each one :) But I read through a few times and removed all acronyms that were only ever used in expanded form, and linked or expanded the rest. I believe the acronym situation is now Acceptable. Leijurv (talk) 06:07, 10 October 2021 (UTC)
This can be a bit too demanding, but incorperating criticisms to the develop history would be epic
Oh god... I don't know if that would make conceptual sense. I struggle to imagine a way to do that cleanly, I'm not sure that would be better than what we have now. Leijurv (talk) 06:34, 7 October 2021 (UTC)
(suggestion from Discord) We have a lot written about the construction history of the first SLS, for Artemis 1. We should also write similar sections for the other ones being built. Artemis 2 had a forward join very recently and the spray-on orange foam is being applied. Artemis 3's main liquid hydrogen tank is assembled. And we should also write about Artemis 4 through whatever and all the contracts that have been signed for future parts ordered. Leijurv (talk) 05:59, 10 October 2021 (UTC)
I don't think so, if it doesn't work well in this article I think it should instead go into each mission's page. Artemis 1 basically already has this with its table of stacking progress and such. Leijurv (talk) 06:58, 10 October 2021 (UTC)
Although, I still think it would be good to get more than just that one source [7] for construction progress of artemis 2 through 4. Leijurv (talk) 06:33, 11 October 2021 (UTC)
Maybe we could reference the occasional NASA press releases when a major milestone occurs or the addition of images(and their captions) to images.nasa.gov when a (usually more minor) milestone is achieved? DeltaDizzy (talk) 15:24, 14 October 2021 (UTC)
(suggestion from Discord) A section on potential applications beyond Artemis. We already have some sources cited for this (e.g. we already cite [8] and [9]), we just should write about them, what SLS brings to the table, etc. For example we could write about how SLS would have made Europa Clipper get to its destination faster (even though it could not be done due to the vibration issues). Some others are Luvoir, Lynx, Europa Lander, Interstellar probe, Persephone, Neptune Odyssey. Leijurv (talk) 05:59, 10 October 2021 (UTC)
(suggestion from Discord) Talk more about the changes from RS-25D -> RS-25E -> RS-25F. Specifically because they don't align with "block boundaries" and it's basically constant improvement within a block (sort of). It has a nontrivial impact on cost and thrust. Several percent more thrust is a big deal. I mentioned some of this info at Special:PermanentLink/1049129520#New_lede. Was previously reverted by Fcrary in Special:Diff/1038843853 and Special:Diff/1038952752 on grounds of WP:OR/lack of WP:RS, so solid sources are needed. Some ideas are [17], [18], [19], and [20] which is an image from [21]. Leijurv (talk) 05:59, 10 October 2021 (UTC)
Speaking of blocks, we might want to mentions all of the changes in the block graphics to prose, for assesibility and MOS compliance. You might wabt to scrool up in Wikimedia discord. CactiStaccingCrane (talk) 06:50, 10 October 2021 (UTC)
GA criteria: there are some things mentioned in the lede (such as deep space exploration) that are not mentioned elsewhere in the body. Although perhaps this would be fixed by talking about the interstellar probe ^^^ Leijurv (talk) 06:36, 10 October 2021 (UTC)
Should revisit all the image sizes, like all the upright=1.2 and such, I think CRS-20 added those or something. All unnecessary ones should be removed. Leijurv (talk) 06:36, 10 October 2021 (UTC)
This section need to be written as prose, because of accessibility and MOS. Also, it makes that section a lot more nuanced. CactiStaccingCrane (talk)
That section that you've linked is already prose. Did you mean #Variants instead of #Upper stages? The table is just an aid to explanation that is already in prose. The numbers for payload can also be found in the infobox. Leijurv (talk) 06:23, 11 October 2021 (UTC)
Not done What information specifically is only in the table, and cannot be found elsewhere? There's nothing wrong with tables lol, such as the table down below for the planned future launches of SLS. Leijurv (talk) 06:37, 11 October 2021 (UTC)
Oh wait, sorry, did you mean the three exploded diagrams? Those used to be down in the gallery, they are not "load bearing" they're just visuals. Again I'm open to the idea but what specific bits of information are missing from prose? Leijurv (talk) 07:58, 11 October 2021 (UTC)
What information specifically, please? Do you mean, like, naming all the little components and bits and bobs? For example, looking specifically at File:Block_1_70t_Crew_Expanded_View.jpg, the only thing I can see that belongs on this article (and not on Orion (spacecraft)) would be something like The core stage is attached to the ICPS using something called a "Launch Vehicle Stage Adapter", is that what you mean? I mean I suppose we could say that, but there's an unlimited pool of more and more technical detail we could go into of how it all fits together. At that point I would defer to WP:DUE and say that the components we should talk about are the components that WP:RS talk about. Leijurv (talk) 17:52, 11 October 2021 (UTC)
I think that the differences between blocks are already covered in prose. Unless there's something specific in those diagrams that you think should be in prose but isn't, I say DoneLeijurv (talk) 05:01, 13 October 2021 (UTC)
You might want to remove ( ), and rephrase the facts inside them. CactiStaccingCrane (talk)
A bad example: (Although these savings may have included a portion of costs related to the delay in launch schedule; a commercial alternative could launch sooner than SLS)
Hi, I am the reviewer, CactiStaccingCrane (talk). I have helped fixed a lot of small errors, as well as bigger ones such as organisation of the article. I am not exactly sure if the 4 (currently not assessed) criteria has been met, so I want someone with more experience to hit home with the review. For you, @Leijurv: you might want to take a look at the criteria and explain why article met them. In the meantime, I would continue review as much as I can. Good luck! CactiStaccingCrane (talk) 01:21, 10 October 2021 (UTC)
I am not quite ready yet to say that the article meets all criteria. I still need to rearrange some things, fix some acronyms (expand them, or remove them), etc. Of course, I will continue to go through the rest of the things you've mentioned, and of course if someone else wants to make specific suggestions that would be very welcome. Leijurv (talk) 04:03, 10 October 2021 (UTC)
I wouldn't review it, but I just want to mention that cleanup tags need to be addressed (sorry if it was discussed before): [altitude and inclination needed], US$2.257[inconsistent], the Exploration Upper Stage[inconsistent]. Artem.G (talk) 08:22, 10 October 2021 (UTC)
The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
Core stage detail - eg avionics - and possible split
I'd like to see/add a lot more detail on the core stage, eg. on its constituent systems especially the avionics (3 flight computers, each of triple PowerPCs ...), IMU, APUs ... but maybe it would make sense to split/start an SLS core stage article that could also take much of the detail of core stage construction and green run testing ? - Rod57 (talk) 10:28, 18 October 2021 (UTC)
Reorganization
@CactiStaccingCrane: I WP:BRDreverted your changes because while reading through, I think all of them make the article's organization less sensical.
Launch costs makes much more sense as a subsection under Funding, it should not be its own top-level section.
Criticism should not be a subsection under Funding. Not all criticism is about cost.
Development should not be the first section. The origin of SLS could be mentioned near the top, but the detailed history of alternatives considered and construction is out of place. It makes more sense to have description of what the SLS is, as the first section after the lede.
Some images were moved to the left sidebar rather than the right. I suppose this could have been because of the infobox? This is, I suppose, part of the previous bullet, where cramming development up top makes it less readable since the images end up on the left. Whereas, the previous setup with Description at the top didn't have this problem.
The SLS block evolution image that was added shows the old design with black/white instead of orange colored SLS, this is more confusing than explanatory.
There may have been more changes, but these are the ones I saw on first readthrough, and I don't think any of them make the article better. Leijurv (talk) 21:33, 8 February 2022 (UTC)
What can we say about launch mass of the block 1, 1B and 2
What can we say about launch mass of the block 1, 1B and 2 ? Article has initial thrust figures, but not gross lift-off mass. - Rod57 (talk) 12:51, 22 February 2022 (UTC)
Lead image
As NASA prepares for the rollout for WDR, we're getting to the point where the lead image should be switched from a render to a real image, in my opinion. For example, see this image, which, if it were taken from a different angle and were higher resolution, would work well as a lead image. I see the comment Do not replace with hardware until a similar pic on the pad becomes available on the lead image in a comment, which I agree with. Are there other criteria that we should think about? Does it really need to be out on the pad, or could we use a pic from inside the VAB. Thoughts? Leijurv (talk) 20:30, 16 March 2022 (UTC)
@Ultimograph5: Haha, looks like you beat me to it. That's what I get for not being on top of my game during the rollout. I may wait for the image to show up on images.nasa.gov and swap it out, because those are generally higher quality than Flickr. But, good timing, good choice, I like your crop, overall thumbs up! Leijurv (talk) 00:02, 18 March 2022 (UTC)
Thanks! I'm thinking if a helicopter shot of it on 39B eventually pops up, it might be good to make that kind of image the lead. But until then I think this image is more than good! Ultimograph5 (talk) 00:06, 18 March 2022 (UTC)
I should've notice this earlier when assessing SLS for good article status. This article contains a section for indiscriminate criticisms (they should be integrated), as well as not including opinions that favor the program. CactiStaccingCrane (talk) 06:12, 1 April 2022 (UTC)
This article contains a section for indiscriminate criticisms (they should be integrated) I disagree that they should be integrated.
not including opinions that favor the program As I mentioned in my edit summary, I disagree that we need to include opinions that favor the program into that section. We would, if it were WP:DUE, but when you look at the criticism section (mostly about cost / funding), we would need WP:INDEPENDENTWP:RS opinions that speak positively about how much SLS has cost. I don't even know if ANY exist, let alone enough for it to be WP:DUE (and not WP:FRINGE) to mention. Leijurv (talk) 03:05, 2 April 2022 (UTC)
A criticism section is intrinsically negative. There is no need for balanced views so long as they are rational and supported with evidence. In most cases the most positive that criticism can be is going to be silver lining such as, "It exploded shortly after launch but it was a beautiful fireball in the sky..." This is a very political program and no matter what criticisms it faces from the public or NASA itself, it will continue to be funded beyond any rational limits. The OIG says 4.1 billion per launch but with the dumpster fire that was Constellation added on, that number goes to more like 7.6 billion per launch. It will still get funded regardless despite the fact that most people within nasa would rather spend that money on science rather than an Alabama jobs program. The criticism section has been repeatedly neutered and it needs to start swinging back towards actual reality. This is a rocket that is supposed to support moon missions that can't actually land anything on the moon. SandowTheHeretic (talk) 02:11, 25 April 2022 (UTC)
@SandowTheHeretic: Ok, this is a little much, you took a well cited paragraph (even with page numbers) that explained the cost breakdown of SLS/EGS/service module/Orion, deleted it, and replaced it with just saying that SLS is 4 billion. Come on. Leijurv (talk) 17:34, 25 April 2022 (UTC)
Which is the most current official pricetag from an oversight audit. The previous number which I'm mostly responsible for was the best official numbers at the time and was the best that could be pushed through given some editors insisting on numbers in the 500-800 million range. Look at the dispute resolution on it if you care. Over 2 billion is a pretty general figure and 4.1 billion is an actual specific number based upon the best current data. It is what nearly every other webpage on the subject currently references. The real cost until 2030 is more like 7.6 billion per launch including development so 4.1 is still a pretty mild figure. Here are more references but they are pointless as they all reference the same source document which is what I referenced with the revision.
@SandowTheHeretic:The previous number which I'm mostly responsible for was the best official numbers at the time and was the best that could be pushed through given some editors insisting on numbers in the 500-800 million range. Look at the dispute resolution on it if you care. Now that is ripe! Referring me to a discussion where I was by far the largest contributor by edit count or word count. I'm not sure about mostly responsible, perhaps look at Talk:Space Launch System/Archive 3 and Talk:Space Launch System/Archive 4, ctrl+f search for my username leijurv versus yours. We were on the same side in that one. most current official pricetag from an oversight audit ... was the best official numbers at the time Also, if you let me refresh your memory, that isn't accurate. At the time in 2020, the OIG for europa clipper said $876M for SLS, which you argued against.
That humor aside, you're just misinterpreting the source. 2.2 billion is the cost for SLS, 4.1 billion is the cost for the whole mission including payload. Every source agrees on this. The paragraph you removed explains this clearly.
Regarding sourcing for this, we don't have conflicting sources, we're both referring to the same OIG. For the three extra you linked, the first has a paywall, but the second says Later in the hearing, Martin broke down the costs per flight, which will apply to at least the first four launches of the Artemis program: $2.2 billion to build a single SLS rocket, $568 million for ground systems, $1 billion for an Orion spacecraft, and $300 million to the European Space Agency for Orion's Service Module. NASA, Martin said, had checked and confirmed these figures. This is straightforward.
If you want to put the 4.1 billion figure somewhere, put it on Artemis program or Artemis 1 I'd say. That would be supported by the sources: the secondary ones you linked were careful to say that "4 billion" is the cost of the Artemis missions, not the cost of the SLS. If you want to replace "over 2 billion" with "2.2 billion" I'd say that could be reasonable. Leijurv (talk) 20:54, 25 April 2022 (UTC)
What on Earth is a "block"?
Is a block like a phase of development? A version? A stage? A configuration? Where did the term come from? It's not normal English, so explain it on first use. ★NealMcB★ (talk) 15:39, 30 June 2022 (UTC)
It's not terribly common, but it's certainly English. It refers to the government buying a number of identical, major items of the same design (a block buy), with the implication that the next purchase will be of the same thing but with a modified design. Fcrary (talk) 19:01, 30 June 2022 (UTC)
The SLS is being developed in three major phases with increasing capabilities: Block 1, Block 1B, and Block 2.[6] I think this explanation in the lede is fine? "Block 1" is the name of the first major phase of development towards increasing capabilities. How could it be phrased better? Leijurv (talk) 19:29, 30 June 2022 (UTC)
Yes, Bubba73, million Newtons. I've linked the first occurence of the "MN" abbreviation in that table to make it more grokable by diverse global readers of the article. N2e (talk) 13:21, 25 July 2022 (UTC)
The "Then-planned launch date history" table, with the meticulous and complete source citations for all of the nearly six-years of schedule slips, is great! For a US government funded program that is spending US$30 billion+ of public funds over a decade or so, the US public, and global readers of the English Wikipedia, will appreciate the encyclopedia of human knowledge covering this topic well. This curated and well-sourced information makes the article much better!
Having said that, I'm not sure that the best place for the information is in a mere "Note" at the bottom of the article. Seems the table might better be placed in a section on the fascinating history of this very costly government funded rocket program. What are others thoughts on placement? N2e (talk) 13:14, 25 July 2022 (UTC)
It's been in a footnote since about a year ago, the recent edit that I made in March was this one which converted the footnote to a table. Thanks for the compliment on the table, I've spent a while on it. It's actually tricky to figure out, and I left some comments in the wikitext to that effect. Anyway, my opinion is that weighing WP:DUE and looking at other articles, my judgement is that the footnote is about right. I don't have any policy or guideline that specifically says this, it's just a judgement call. I was inspired by the table on the side of James Webb Space Telescope#Cost and schedule issues. That article has many WP:RS talking about the delays as a coherent whole. Like, over the course of JWST's 14 years of delays, there was WP:SIGCOV given specifically to the delays themselves, and the history of said delays. That isn't to say that there aren't similar sources for SLS, in fact this one is a perfect example of what I'm talking about, it's just that this is in the minority of SLS coverage, so WP:UNDUE comes into play. I also wanted to avoid WP:SYNTH as much as possible. Come to think of it, the statement "it has been delayed at least X times" and then a citation to X sources is definitely WP:SYNTHy and should probably be removed. As an example of why, I explained here why two different sources for slips were actually just one slip. Anyway, I think that a table in the body is a bit much, just as a judgement call based on prominence of sources and how much they talk about the delay. However I don't feel extremely strongly about this; I just think that a table in the body is less than ideal. If it were in the body, it should be aligned sort of like how it is in the JWST article, where it doesn't break the flow, but rather complements it. Leijurv (talk) 01:21, 26 July 2022 (UTC)
Usage beyond Artemis
The text in the "Usages beyond Artemis" section is technically correct, but I think it would be better to rephrase it. As it says, all of the listed missions are "proposed". But lots of things get proposed. Currently, NASA has no actual plans to fund, develop or fly any of the listed missions. NASA has just funded some paper studies of the mission concepts and some people have said they would be a good idea. Europa Lander, for example, was something the recent National Academies Decadal Survey specifically did not recommend as something NASA should fund. I think the current phrasing implies there are many non-Artemis missions with a real possibility of actually existing and flying on SLS. Can anyone think of a way to rephrase? Perhaps "missions which have been proposed but not selected or funded"? Fcrary (talk) 15:41, 26 July 2022 (UTC)
I think the sentence is fine as written (although, since I wrote it, "I would say that, wouldn't I" (MRDA (slang))).
While the SLS is only confirmed for use on the first few Artemis missions, many other proposed NASA missions intend to launch on the SLS:
I think this is good because 1. it explicitly says that SLS isn't "confirmed" on these others 2. the others are "proposed" and only "intend" to launch on SLS. I think this accurately covers what you say, which is that NASA has no actualized plans to do these things.
I think the current phrasing implies there are many non-Artemis missions with a real possibility of actually existing and flying on SLS. Wait, but isn't this true? I suppose it depends on how you define "real possibility"?
But a rewrite is of course on the table. I think missions which have been proposed but not selected or funded is a little wordy. I think "proposed mission" clearly gets across the idea that it's just a proposal, no? Maybe we could change "intend to launch" to "would launch", because "intend" conveys a bit too much certainty? And if you really want, maybe we could do [...], many other proposed NASA missions would launch on the SLS, if they were selected for funding and development.? Or something like that? Leijurv (talk) 21:28, 26 July 2022 (UTC)
Broadly, I think that "proposed" means "proposed", and we don't need to weaken it with additional phrases that cast doubt on the proposals. It wouldn't be WP:NPOV to put WP:UNDUE emphasis on the chance that the proposals won't be selected. My thinking is along the lines of MOS:WTW, while your phrasing isn't literally listed under MOS:DOUBT, I feel like the spirit of it might apply. Leijurv (talk) 21:35, 26 July 2022 (UTC)
At some point we do need to case doubt on (or remove) some of those proposed missions. It would be misleading if we listed proposals which have been rejected. So this is really about where to draw the line. The Neptune Orbiter wasn't actually a proposal in the formal sense. It was a concept study to provide the Decadal Survey with reasonably worked out options which they could recommend. They specifically did not recommend that one, and specifically said the plan to on SLS was part of their reason. The same is true of Persephone. The Europa lander was also a concept study rejected by the Survey as infeasibly expensive. I really think we should limit the list of "proposed" missions to those which are still actively under consideration. That would include Interstellar probe, since the Heliophysics Decadal Survey is still in the works and they are considering it as a possible recommendation to NASA. Perhaps this is about what "proposed" means. It actually has a formal meaning when it comes to NASA missions, and that makes it stronger than some concept study someone came up with. If we included all concept studies, we'd have an unmanageably long list. Fcrary (talk) 22:49, 26 July 2022 (UTC)
Ok! I think it's reasonable to remove from that list anything that is verifiably no longer under active consideration. Which would those be, in all? Leijurv (talk) 00:42, 27 July 2022 (UTC)
That might take some digging. Before I do, what would count as "verifiably no longer under active consideration"? All of these are concepts for flagships (Large strategic science missions), and NASA almost always goes along with what the Decadal Surveys recommends. But not always. Is it ok if the mission was a concept proposed for consideration by a Survey and the Survey didn't recommend it to NASA? I'm inclined to say that means it's no longer on the table. If so, we'd leave Interstellar probe on the list, since the heliophysics Survey isn't out yet. HabEx, Origins Space Telescope, LUVOIR, and Lynx were all considered by the astronomy and astrophysics Survey and it recommended a merged version of Origins and LUVOIR B; I'd have to check if they said anything about launch vehicles for that. Neptune Odyssey, Europa Lander, and Persephone were considered and rejected by the planetary Survey. It recommended a Uranus orbiter instead. Again I'd have to check what that would launch on, and there might be another flagship they recommended which I'm forgetting. But if basing our criteria on the Decadal Surveys' recommendations is acceptable, I'll go off and look up those details. Fcrary (talk) 16:56, 27 July 2022 (UTC)
Yes that sounds good: if a project was plainly aiming to be recommended by the decadal survey (or equivalent), but was not included, and there is no other reason to believe it's still under consideration, then it can be removed from this list. Also the linked article on that project should be updated accordingly, I suppose. For the case of a merged recommendation, let's keep both links but combine it maybe? e.g. HabEx/LUVOIR (replacing the comma with slash). I'm not sure what's going on with habex/origins/luvoir for example (the habex page says it was merged with luvoir?) Leijurv (talk) 20:57, 27 July 2022 (UTC)
I've just gone through the planetary and astro Decadal Surveys, and now I'm not sure if simply deleting the missions which were not recommended makes sense. If we do, we may be left with only Interstellar Probe (pending the still in progress heliophysics Survey) and Enceladus Orbilander, which is the one I'd forgotten about. The astronomy/astrophysics missions may be hard to describe. The Survey did recommend something like those mission concepts, including a merged HabEx/LUVOIR telescope with a smaller mirror than LUVOIR-B as the highest priority. But "something like" is the problem. The Survey basically pushed it off and didn't clearly recommend any of them. Due to high costs and long development times, it recommended a "maturation" program to develop the technologies and have a later Survey (presumably the one for the 2030s) decide what NASA should do. No mention of launch vehicles was made. It's unclear if the reformulated missions, after that maturation program will need to launch on SLS. So those particular missions are off the table, and we have no idea if the ones which are "something like" them will use SLS.
So how about this. Leave the current list intact, with the addition of Enceladus Orbilander, but change the sentence to describe them as "examples of concept studies submitted for consideration". Then add some text saying that Orbilander was recommended, a technology development program to reduce cost and schedule was recommended for the telescopes, so the launch vehicle is unclear, and that the heliophysics Survey is still in progress and considering Interstellar probe. That's wordier than I'd like, but it's accurate and wouldn't reduce the list of missions to just two. Fcrary (talk) 00:27, 28 July 2022 (UTC)
So, something like While the SLS is only confirmed for use on the first few Artemis missions, many other concept studies submitted for consideration intend to launch on the SLS? Sounds reasonable to me! Leijurv (talk) 18:03, 28 July 2022 (UTC)
I also agree in general that given that these other missions mostly have Wikipedia articles, it would be nice to retain links to them, even if we have to rephrase it to "X Y and Z canceled proposals would have launched on SLS". I feel it's encyclopedially relevant, for example given how much time the article spends talking about failed proposals to modify SLS. Leijurv (talk) 20:58, 28 July 2022 (UTC)
SLS Lead Paragraph - location and dates
Pasted from here: Hello! I noticed that you reverted my edit on the lead paragraph of the SLS article. Appreciate the edit was reverted to keep the lead simple, but I don’t think adding a location and some dates adds any complexity. SLS is all over the news at the moment and this is the information that people will be looking for when they search for it, and so I have added this information back in. Starlights99 (talk) 06:43, 11 August 2022 (UTC)
The lede is meant to represent the highest level overview of SLS. I don't even think that the first launch should be the second sentence. That information makes much more sense as front-and-center of Artemis 1 in my opinion. See MOS:LEDE for more. However, perhaps we could compromise as a single sentence, what about something like: The first launch is scheduled for no earlier than 29 August 2022 from [[Kennedy Space Center|KSC]].? KSC could maybe be mentioned, but the backup launch dates are definitely not appropriate to include in the second sentence of the lede on the rocket (not even the article on its first mission). Also, please follow WP:BRD and discuss instead of reinstituting the disputed change, until consensus is reached. Leijurv (talk) 08:02, 11 August 2022 (UTC)
Hi, thank you for moving this here. I felt that it was a good addition of some key information that people would be looking for at this point in time, especially as the launch has been a popular topic recently, which is why I thought it would be good in the lead paragraph. However I do understand your view and am happy to agree with your compromise. Additionally, thanks for the pointer - will review WP:BRD for future edits going forward. Starlights99 (talk) 18:48, 11 August 2022 (UTC)
Ton-force is Earth-centric and is not a standard unit of measure. One ton's gravitational force on Mars will not equal to one ton's gravitational force on Earth. If you really insist on using tons, just remember that 1 MN = 0.1 kilotons of force. CactiStaccingCrane (talk) 16:34, 29 August 2022 (UTC)
Units on page should be in US Customary Units
SLS universally uses US Customary Units even in technical documentation. We should not be rewriting that from such units, and even sourcing them directly in the page after-conversion rather than using conversion templates. Ergzay (talk) 06:12, 17 August 2022 (UTC)
Firstly there's a general ignoring of this rule from WP:MOS "In a direct quotation, always retain the source's units. Any conversion should follow in square brackets (or, an obscure use of units can be explained in a footnote)." Units in this article are generally given after the conversion, rather than maintaining the source's units, even if conversion is deemed appropriate. Ergzay (talk) 06:22, 17 August 2022 (UTC)
Secondly the rule "Scientific articles may also use specialist units appropriate for the branch of science in question." applies here. In US rocketry, for most historical rockets, they were explicitly designed in and continue to be designed in US customary units for many vehicles. The "specialist" in the above quote refers to the specialist units in question as things like "Mlbf" for "million-pound-force" and similar units. Here's an example of such use (one of the sources on this page): https://ntrs.nasa.gov/citations/20150016519Ergzay (talk) 06:22, 17 August 2022 (UTC)
@CactiStaccingCrane Thanks for changing some more entries, however I noticed you just flipped the units. Often what happened is that these entries were originally in US Customary Units in the source but the editor who put them into the article converted them in-place into metric, losing the original US customary unit. Back converting them in the wiki from SI units back to US customary units now has likely resulted in some incorrect values because of rounding.
If you have the time (I haven't yet), could you also re-source the original US customary unit (often using the attached source, if it's there) and use that in the article instead (while also providing a converted SI unit)? Ergzay (talk) 17:53, 30 August 2022 (UTC)
The SLS core stage propellant tanks are rated for 22 fuel load cycles, with 9 cycles allocated for testing.
This has resulted in confusion where 9 load cycles are being reported as the limit.
This information should be added to the main page.
"Currently, the SLS core stage can still be loaded with propellant and pressurized 20 more times for a total of 22 cycles. Rocket stages like the core stage are designed to be loaded with cryogenic propellant and pressurized a specific number of times. These are called cryogenic loading cycles. Before Green Run testing began, SLS had allocated nine cryogenic cycles for testing at NASA’s Stennis Space Center..."
quote from [Secondary Ref URL] and [Primary Ref URL ].
Following a question on StackExchange, it's clear that the statement that the SLS is the successor to the Shuttle is at best unclear and at worst untrue, because the mission objectives for the SLS and Shuttle do not even slightly overlap. The SLS is (as all 3 references say) actually the successor to Saturn V.
Amen! The SLS is designed for lunar flight to succeed the Apollo program. Its design just happens to incorporate some Shuttle-derived components (External Tank and Solid Rocket Boosters), but that doesn't mean it's a "successor to the Shuttle". (BTW: please sign your Talk page posts by typing four tildes ("~~~~") at the end. This signs it with a timestamp. JustinTime55 (talk) 20:52, 23 September 2022 (UTC)
On further reflection, perhaps the intent of the original author of that phrase is that SLS (plus a spacecraft) will replace the Shuttle to resume NASA's human spaceflight capability. Still, it's meant to succeed Saturn V is the right thing to say. JustinTime55 (talk) 22:42, 23 September 2022 (UTC)
Improved wording needed
The section on the Core stage includes the phrase "expended use". I thought this might be a typo for "extended use", but I suspect it really means "one-off use" (by contrast with the use of similar engines on the space shuttle). I feel a better phrase should be used for clarity of communication.Elroch (talk) 16:45, 29 September 2022 (UTC)
My understanding that "payload to TLI" is understood as the payload that is put into an orbit from which TLI is possible? Leijurv (talk) 21:56, 20 November 2022 (UTC)
Is there a better phrase? Like, is this the difference between a geosynchronous orbit versus a geosynchronous transfer orbit? Leijurv (talk) 21:56, 20 November 2022 (UTC)
By your reasoning, if Artemis II is TLI, then Artemis I should be lunar orbit. If it is the next step after the final impulse provided by the launcher... Hektor (talk) 02:57, 21 November 2022 (UTC)
I am not an expert on this, sorry if this is wrong! My understanding that TLI is not a specific orbit, but a maneuver that takes a spacecraft from an orbit around earth to an orbit around the moon. Orion does that maneuver. SLS delivers Orion to the earth orbit from which this maneuver is possible. Therefore, "payload to TLI", with respect to SLS, reasonably means the payload that SLS delivers to a place from which TLI can occur? Am I correct when I say that the confusion comes from how the other two columns are orbits (LEO and HCO), whereas this column is a maneuver, so it's ambiguous whether it means payload to the beginning or end of the maneuver? Leijurv (talk) 04:41, 21 November 2022 (UTC)
Also wait, no, ICPS does the TLI burn, not Orion. And ICPS is very arguably part of SLS, it's the second stage, and Orion is the payload. Orion is delivered into a lunar orbit by SLS (the first and second stages together). Leijurv (talk) 05:00, 21 November 2022 (UTC)
We're talking specifically A2, in which SLS drops the partially-fuelled ICPS and Orion off at a 71760 x -5km suborbital trajectory. Sub31k (talk) 05:25, 21 November 2022 (UTC)
For all other Block 1 missions SLS is throwing the spacecraft onto its merry moon-bound way. But it doesn't hold for A2, yet it's still listed as a TLI mission for the SLS. I think Hektor's got a good point. Sub31k (talk) 05:28, 21 November 2022 (UTC)
Table about localisation of ICPS or EUS
I think it would be good to indicate, for instance with a table, the fate of each SLS Upper stage, per mission. I understand for instance that the ICPS-1 now orbits the Sun. Fate can be, Earth entry, orbits the Sun, orbits Earth, impact with the Moon, Escape trajectory, etc. Hektor (talk) 23:15, 3 February 2023 (UTC)
Budget question
Fiscal year 2019 says 2.144 billion in the table, but the cited source [22] says 2.150 billion. Every year that I've checked at random has been close but not quite right. What's going on? Also, it says Enhanced Upper Stage (EUS) development (non-add)*** but we say that the EUS costs are included with the SLS costs. It appears they are not. Should we be adding them in for consistency in the years where they weren't (per WP:CALC)? I can't figure out who added this number since the "Who wrote that?" plugin doesn't work on tables, otherwise I would ping them. Thoughts please? Leijurv (talk) 06:00, 7 October 2021 (UTC)
The Budget sections says "Included in the above SLS costs above are (1) the Interim Cryogenic Propulsion Stage (ICPS), a $412 million contract[103] " but the reference (now says $1 Bn) and its archived version don't have that figure. And the ref doesn't say if it has been increased to include delivery of 3 (rather than 1) flight ready ICPS. - Rod57 (talk) 17:35, 1 April 2023 (UTC)
This article incorporates text from this source, which is in the public domain.
Done Has been addressed. Special:Diff/1048452526 Leijurv (talk) 03:16, 6 October 2021 (UTC)
Not done (just wanted to tag this as not done, still pending resolution of Special:Diff/1048773333) Leijurv (talk) 06:25, 10 October 2021 (UTC)
![[20]](https://www.nasaspaceflight.com/wp-content/uploads/2020/12/RS-25-Evolution-For-SLS.jpg){kind=link}
! Long road ahead though, I think this article should aim for the stars! (pun intended) CactiStaccingCrane (talk) 07:24, 15 October 2021 (UTC)
