Talk:Parking orbit

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cn tags
Tagging


 * This must be dealt with through the use of tank diaphragms, or ullage rockets to settle the propellant back to the bottom of the tank. A reaction control system is needed to orient the stage properly for the final burn, and perhaps to establish a suitable thermal orientation during coast. Cryogenic propellants must be stored in well-insulated tanks, to prevent excessive boiloff during coast. Battery life and other consumables must be sufficient for the duration of the parking coast and final injection.

and


 * The Ariane 5 does not usually use parking orbits. This simplifies the launcher since multiple restart is not needed, and the penalty is small for their typical GTO mission, as their launch site is close to the equator. A less commonly used second stage (EPS) has multiple restart capability, and has been used for missions such as the Automated Transfer Vehicle that use parking orbits.

which are unsourced. Also tagging another para with no source. All of this information needs to be cited to something. —valereee (talk) 11:27, 17 July 2021 (UTC)


 * Thank you very much for explaining your reasoning and what you think needs to be sourced. This enables a rational discussion.


 * For your first point, I think a cite is reasonable, and I've provided one. The only problem is that it's more than 300 pages, and the information is scattered within it.  This leads to your second point...


 * For your second point, I do not believe a direct citation is in the reader's best interest. There are many factors that go into rocket design, and parking orbits are just one of them.  Therefore it's better (I believe) to link to the article on the rocket, which in turn has the primary references.  This is much better for the reader in another way - if the link goes directly to the correct section of the article (which I have done), the information the reader seeks is in the first few paragraphs, and directly on the screen.  Compared to a direct reference, it's one less click, does not lose the reader's place in the article, avoids the need to find the desired fact in some huge reference document, and provide sufficient information to satisfy their curiosity.  If they want to go further and check the detailed reliable source, it's right there.


 * This of course implies the detailed question is answered in the pointed-to article. When it is not, a direct reference is appropriate (example "The Ariane 5 does not usually use parking orbits.")  I added it here, but it might make more sense to add it to the Ariane 5 article. LouScheffer (talk) 14:51, 17 July 2021 (UTC)
 * @LouScheffer, I'm afraid that's not good enough. We expect sources to be here. I'm going to add those two templates back in. If you don't want to go find them, it's fine, but we don't leave unsourced content in articles without at minimum tagging them. This is settled consensus. —valereee (talk) 16:14, 17 July 2021 (UTC)
 * I have a suggestion. Instead of marking with 'CN', why don't you copy over the actual reference(s) from pages referred to that already have reliable sources?  The sentences already link to the correct spot in each page, and the references are already in Wikipedia format, so it's a simple edit.  This way you would not only identify the problem, but also fix it, all in one step. LouScheffer (talk) 19:56, 17 July 2021 (UTC)
 * Seriously? To take just the first tag, which is on The Centaur and Agena families of upper stages were designed for such restarts and have often been used in this manner. The last Agena flew in 1987, but Centaur is still in production. The Briz-M is also capable of coasts and restarts, and often performs the same role for Russian rockets.: the para has 5 links, 3 of which are to specific article sections, each section containing multiple links to sources. You're suggesting I go visit all those links, access the sources -- some of which I'll need to order from the lib, some of which I'll probably have to go into the lib for, some of which I likely won't be able to access -- read them, figure out which of them supports which assertions in that para, and transfer that source into the correct spot over here? That's your idea of a "simple edit" lol? I am just...well, laughing.
 * No one is requiring you to fix this. If you don't want to fix it, that's fine. Just walk away. Someone, at some point, will come along, think, "Oh! I know a bit about this subject -- I bet I can figure out where to find that!" And they'll fix it. Until then, it gets a tag. —valereee (talk) 20:30, 17 July 2021 (UTC)
 * I’ve explained this to you on my talk page, at this point you’re being willfully ignorant about our guidelines and policies, thats not going to fly. If you truly believe that direct citations are not in the reader's best interest then you should find a different project to work on. Horse Eye&#39;s Back (talk) 17:05, 17 July 2021 (UTC)

Source verification of Design Challenges section
This states: Use of a parking orbit requires a rocket upper stage to perform the injection burn while under zero g conditions. Often, the same upper stage which performs the parking orbit injection is used for the final injection burn, which requires use of a restartable liquid-propellant rocket engine. During the parking orbit coast, the propellants will drift away from the bottom of the tank and the pump inlets.[4] This must be dealt with through the use of tank diaphragms, or ullage rockets to settle the propellant back to the bottom of the tank. A reaction control system is needed to orient the stage properly for the final burn, and perhaps to establish a suitable thermal orientation during coast. Cryogenic propellants must be stored in well-insulated tanks, to prevent excessive boiloff during coast. Battery life and other consumables must be sufficient for the duration of the parking coast and final injection.[5]

From the referenced document (Taming Liquid Hydrogen: The Centaur upper stage rocket, 1958-2002), here are the page numbers where the points of this paragraph are addressed: LouScheffer (talk) 22:43, 18 July 2021 (UTC)
 * Zero G restarts: Page 50
 * Need a liquid rocket to restart: Page 176
 * Drift of propellent: Has it's own reference, but mentioned on 66, 84-85, 150
 * Diaphragms of Ullage Rockets: Reference [4], already existing
 * RCS needed for orientation: Page 149
 * RCS needed for thermal control: Page 150
 * Well insulated tanks: Page 150
 * Battery life must be sufficient: Obvious, but stated explicitly on Page 111
 * Other consumables must be sufficient: Page 108


 * I only challenged the second source, are you saying that reference 4 also is insufficient for the statement its being used to source? Horse Eye&#39;s Back (talk) 23:12, 18 July 2021 (UTC)
 * Please pull quotes not just page numbers, for instance on page 108 I’m not finding anything about "Other consumables must be sufficient” the "parking coast" or the "final injection." Horse Eye&#39;s Back (talk) 23:15, 18 July 2021 (UTC)
 * "For attitude control and propellant settling during the long coast period, engineers increased the supply of hydrogen peroxide". LouScheffer (talk) 23:58, 18 July 2021 (UTC)
 * I’m not seeing a statement about all upper stages there, nor am I seeing anything about final injection. Horse Eye&#39;s Back (talk) 00:16, 19 July 2021 (UTC)
 * The rest look bub as well, and thats on top of the fact that you pointed out that 4 doesnt support the whole bit its meant to support... This is the problem with trying to jam a source onto material that was never sourced from it in the first place, it simply doesn’t fit. Not only is it lazy but because the source doesn’t actually make the statement its disruptive. Horse Eye&#39;s Back (talk) 00:17, 19 July 2021 (UTC)
 * The very first sentence says "a Centaur upper stage rocket", and the fact that it's an upper stage is repeated 140 times throughout the document. And the reason they specify increase for the long coast is because it already had enough for the first coast and the final injection.  This is customary - when you specify battery life for a cell phone, you specify to the end of the last call, not the end of the idle time.
 * In general, I believe many technical articles are not written by starting with a specific source, and then distilling it. Instead, an editor creates an overview of the main ideas from a whole field - ideas that have been around for decades and are entirely non-controversial.  As the field evolves through various technical articles, there in fact may be no simplified description phrased the same way as the wikipedia article.  In fact, this synopsis is exactly what the Wikipedia article is meant to provide.  So the references may well point to specific cases, and not explicitly state (for example) "and this would apply to all other liquid fueled second stages". The reader of the article is expected to understand this, as the reader understands a math proof involving variable 'x' would be just as true if the variable was called 'y', or indeed any other name, though this is almost never called out.  This is especially true in mathematics, where understanding a proof (their version of a reliable source) likely requires an understanding of the field as a whole, but is true of many other fields as well.  LouScheffer (talk) 01:45, 19 July 2021 (UTC)
 * Thats exactly my point, this is a page for parking orbit not the Centaur upper stage rocket. The source needs to make universal statements about all upper stages (not just Centaurs) because thats whats on the page. If you can find something which says thats how it works on this sort of article I’l read it but “In general, I believe” is not gonna fly. This is not mathematics, please follow WP:VERIFY and WP:RS. You’re edit warring a valid tag off the page and refusing to provide an explanation which actually satisfies policy. That is not good my friend. Horse Eye&#39;s Back (talk) 03:58, 19 July 2021 (UTC)
 * and myself have been extremely patient in explaining this to you, if you want to take this to a noticeboard you can but as of now you do not have consensus to remove the tags from the article. Horse Eye&#39;s Back (talk) 04:02, 19 July 2021 (UTC)
 * The list of characteristics is immediately recognizable and standard to any professional in the field. I don't know why there's controversy over it establishing those features as necessary for any upper stage (other than insulated tanks, for cryogenic propellant stages, which is already disclaimered).  What's unclear about that?  Georgewilliamherbert (talk) 02:16, 21 July 2021 (UTC)
 * The argument isn't whether this is immediately recognizable to any professional in the field but whether it's verifiable by the average reader. No one is arguing these statements are somehow dubious, only that we should be providing some source for the reader who isn't a professional in the field. I mean, if this is simple stuff, isn't there a HS or college textbook somewhere that says it? Someone somewhere must be teaching this to beginning students rather than assuming prior knowledge? —valereee (talk) 15:55, 21 July 2021 (UTC)
 * I don’t recognize the standard "immediately recognizable and standard to any professional in the field” from any of the policy, guidelines, or discussions I’ve come across. Is this a personal opinion or a policy based argument? Horse Eye&#39;s Back (talk) 15:59, 21 July 2021 (UTC)
 * Combined reply. The question is whether the information is (a) uncontroversially true and (b) verifiable in a reliable source.  If it is both of those, absent any serious reason to question it or the source or the person wanting to include it, ... what's the problem?  Do you believe that the source isn't reliable?  Do you believe that the source doesn't say these things about parking orbits?
 * The same information can be found in the classic textbook "Spacecraft Mission Analysis and Design" by Wertz and Larson, the more modern revision of it "Space Mission Engineering: The new SMAD" by Wertz, Everett, and Puschell; Fortesque and Stark's "Spacecraft Systems Engineering", parts of it in Sutton's "Rocket Propulsion Elements" where it's talking about stages for in-space use such as transfer orbits and so forth. Main and reaction control and settling propulsion and stage design elements of it are in the upper stage design sections of Huzel & Hwang's NASA SP-125 or its commercial textbook version "Modern Engineering for Design of Liquid Propellant Rocket Engines".  I believe it's largely in Larson McQuade & Pranke's "Human Spaceflight Mission Analysis and Design".  There are a ton of more specialized AIAA publications that should have it as well, but those are the textbook type and professional general reference type books that will have it.
 * None of which should be necessary to list out in excruciating detail, because the existing source is correct and reliable, even if not the most general purpose possible source.
 * Lou's a professional in the field, and adjacent fields. I'm a professional in the field.  I've designed upper stages and done mission designs using parking and transfer orbits.  We're both extremely long time Wikipedia users, and understand reliable sourcing and accuracy.  Why on earth was this so controversial here?
 * You're asking for gold plated sources that are the most accessible to new users. Having such sources is a best practice, sure.  For eventual perfection of articles.  The information was accurate, wasn't controversial, and was cited in a reliable source.  That's enough for tags to come off.  Someone can at their leisure later establish a best list of most accessible technical textbooks in aerospace engineering and orbital dynamics, and create a citation gnoming project for themselves or others to upgrade articles with the most accessible technical references.  Lou doesn't have to do that here and now, he just needs a sufficient citation.  Georgewilliamherbert (talk) 08:26, 23 July 2021 (UTC)
 * Actually, I'm only talking about the two cns on the page. I don't have an opinion on the source HEB is discussing. So I think this is two different discussions maybe? —valereee (talk) 18:09, 23 July 2021 (UTC)
 * You appear to misunderstand, nobody is challenging that currently. LouScheffer has both provided a WP:RS and edited the statement into conformity with that RS. Originally the statement was entirely unsourced. Horse Eye&#39;s Back (talk) 18:23, 24 July 2021 (UTC)