Talk:Spacecraft electric propulsion
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![]() | The article's lead section may need to be rewritten. The reason given is: it is a jumble of poorly written sentences in no particular order, many of which don't belong in the lede at all. (March 2013) |
2006
[edit]I'm really surprised there is no electric propulsion page... The ion thruster link seems to be the closest, however it is not entirely accurate... (e.g, resistojets don't utilize ions). Someone needs to write this. Allen314159 05:30, 24 August 2006 (UTC)
Other vehicles
[edit]This article as of 29 August 2007 only discusses its use in spacecraft. This mode of propulsion is also found in many other forms such as automobiles, locomotives, and ships. Those usages of electric propulsion should be mentioned here. After all, spacecraft do not have a monopoly on this technology, nor has electric propulsion been used successfully in space yet, but has been used terestrially for decades. - Deeplogic 20:01, 29 August 2007 (UTC)
I don't think it would be right to discuss the propulsion of other electric vehicles, on this page. This page more exists because this is the common way to characterise electric propulsion for spacecraft. There already exists a page called 'ion thrusters', but it is not right to call all spacecraft electric propulsion 'ion thrusters' - simply because some do not use ions, and it is a little too general and non-scientific. I think the problem really lies in the title of this page - should it not be 'spacecraft electric propulsion'? The a seperate page for 'electric propulsion'? This would help clear up any ambiguities. Cheers
Charlie —Preceding unsigned comment added by 212.139.66.62 (talk) 15:44, 7 September 2007 (UTC)
- I agree that the name "electric propulsion" sounds like it might include electric automobiles, ships, etc. Currently, those things are all discussed in the electric vehicle article. Is there a better way to help our readers who may stumble across one when they are really looking for the other one? --68.0.124.33 (talk) 05:01, 10 July 2008 (UTC)
- I also agree. If it were me, I'd rename this page "electric spacecraft propulsion" and make "electric propulsion" a disambiguation page. Anyone object? --IanOsgood (talk) 20:57, 1 March 2010 (UTC)
"Electric propulsion" is a term of art very commonly used in the aerospace industry. Consider, for example, the "electric propulsion year in review" published in every December issue of Aerospace America Magazine by the American Institute of Aeronautics and Astronautics (AIAA) or the biannual "International Electric Propulsion Conference" (IEPC) attended by a few hundred specialists in electric propulsion (see http://www.iepc2009.org/). The AIAA even has a dedicated electric propulsion technical committee (see https://info.aiaa.org/tac/PEG/EPTC/default.aspx). For this reason, the page should be renamed "electric propulsion", the commonly used term within the industry. You may still want to have an electric propulsion disambiguation page for other uses of the term (I'm not sure what Wikipedia's policies are on this), but you should maintain a page called "electric propulsion" that is about electric propulsion for spacecraft..75.4.9.27 (talk) 23:27, 8 May 2010 (UTC)
- I'm really, really, not sure. There's also electric motor to consider; should they include ion drives? Ion drives do produce mechanical motion... I suspect yes. Perhaps electric propulsion is the main article, and electric motor is the subarticle??- Wolfkeeper 21:08, 1 March 2010 (UTC)
- It's very dangerous to make articles not called what they contain; electric vehicle is about vehicles, whereas electric propulsion is about propulsion techniques. I think that also extends to this article; an article called 'electric propulsion' should cover all electric propulsion until the article gets too big, then it should be split. Right now, the article is tiny.- Wolfkeeper 21:16, 1 March 2010 (UTC)
Disambiguation page
[edit]It now seems odd that Electric Propulsion diverts to a page on electrically propelled space vehicles with only a feed back to Electric Vehicles. And even that page mainly considers road vehicles, apart from the section on vehicle types. Would it not be more sensible to make the Electric Propulsion page into a disambiguation page with entries including these two and Railway Electrification System, Submarines#Propulsion etc.? If no one objects, I'll do it in a day or two. Chris55 (talk) 13:52, 31 May 2010 (UTC)
I agree that there should be a disambiguation page. I also think (as I stated above on May 8th), that this page should also be titled "electric propulsion", as electric propulsion is a term of art very commonly used in the aerospace industry. Is this something I can change myself? 137.78.133.222 (talk) 23:01, 1 June 2010 (UTC)
- If you look, you will see that the disambiguation page is there. However I can't agree that "electric propulsion" refers just to the aerospace industry. I'm not surprised that it doesn't have any qualifier when used within that industry - it won't need it. But you will see from the disambiguation page that it's a common concept in many other fields and one needs to consider the average reader - who is probably more interested in cars than space vehicles. If you really want this article to be called Electric propulsion then the usual wiki approach would be to put (spacecraft) after it as a disambiguator. However, create an id for yourself and look at Wikipedia:Disambiguation before doing it. Chris55 (talk) 07:56, 2 June 2010 (UTC)
- Yes, "Electric propulsion (spacecraft)" would be fine. I'll have to look and figure out how to do it.. 137.78.133.222 (talk) 00:08, 3 June 2010 (UTC)
Non-sequitur in lede
[edit]There seems to be an inconsistent non-sequitur in the lede. The first sentence talks about electric motors for providing mechanical energy for spacecraft. The second sentence speaks about spacecraft propulsion, which is more in line with the article subject. But this nonsensical nonsequitur has been present in the article for nearly a year, and I don't know much about electric propulsion, so am a bit reticent to just delete the electric motor stuff. Does it make sense to anyone else? N2e (talk) 06:26, 3 February 2011 (UTC)
- Well, *I* agree with you, but watch what happens when you take out "electric motors" - suddenly a horde of sword-wielding skeletons will restore it to the article. Nobody but Wikipedia editors call the things that push spacecraft along "electric motors". --Wtshymanski (talk) 15:13, 3 February 2011 (UTC)
- The Wikipedia isn't about what things are called. If encyclopedias were about what things were called, then the article 'desert' would be about abandoning things as well as arid regions of the world.Rememberway (talk) 15:33, 3 February 2011 (UTC)
- An electric motor is something that creates motion from electrical power. Examples include rotary motors, linear motors and electrically power thrusters. All convert electrical energy into kinetic energy. An example in the lead is the electrodynamic tether which is a very clear example of an electric motor used for spacecraft propulsion, but every other propulsion system as well can be classified as electric motors, from the definition.Rememberway (talk) 15:33, 3 February 2011 (UTC)
- Thank you for illustrating the point. This is why cat is a redirect to felis catus. --Wtshymanski (talk) 15:44, 3 February 2011 (UTC)
- The felis catus article is certainly at cat, but it's not about cats in general which is at felidae. The cat article is only about housecats, and any of the names 'felis catus' 'housecat' 'domestic cat' 'cat' would doubtless have been pretty acceptable name for the article, and the body of the article text wouldn't have changed more than superficially. That's another good example of how encyclopedia articles aren't about their names, they're about what they state they're about in the lead.Rememberway (talk) 19:04, 3 February 2011 (UTC)
- Basically, in encyclopedias, simply renaming articles (including fixing up the links) you shouldn't change anything very significant; if it does, it's usually not a correctly written article.Rememberway (talk) 19:04, 3 February 2011 (UTC)
- Thank you for illustrating the point. This is why cat is a redirect to felis catus. --Wtshymanski (talk) 15:44, 3 February 2011 (UTC)
- Let's get back to discussing the improvement of this article. I take the point that Rememberway makes that some types of spacecraft propulsion (e.g., rotating, conductive tethers) have certain characteristics of an electric motor. 1) I don't get at all how "electrically powered spacecraft propulsion system is any of a number of forms of electric motors which spacecraft can employ to gain mechanical energy in outer space." as the article lede currently asserts. Moreover, 2) even if there is some esoteric means by which a chemical-reaction rocket engine could be considered an "electric motor", that would be esoteric geek-talk and we ought to strive to write a lede that, while correct, is at least meaningful and grokable to the typical Wikipedia reader. In which case, calling all spacecraft propulsion electric motors should not be what we lead with, and maybe it would fit further down on in the esoteric geeky detail section of the article. So can anyone help me understand my question in no. 1)? and then others please weigh in on no. 2). Cheers. N2e (talk) 19:41, 3 February 2011 (UTC)
- Be bold and good luck. --Wtshymanski (talk) 20:14, 3 February 2011 (UTC)
Formulas Useful
[edit]It would be useful if the formulas for electric propulsion were listed. They are:
Isp and thrust are related to power in this way:
- thrust/(g*Isp)= massflow
- power= .5*massflow*(g*Isp)^2
- power = .5*thrust*(g*Isp)
Andrew Swallow (talk) 22:35, 8 February 2013 (UTC)
Sentence in the lede re. nuclear-fueled interstellar flight
[edit]A dispute has broken out regarding the following sentence, recently added to the lede by Vyacheslav84 (talk · contribs):
- Electrically powered spacecraft propulsion with a nuclear reactor has a slight acceleration, which makes it unsuitable for interstellar flight for a reasonable period[1].
One: IMO this doesn't belong in the lede. No mention of this is made anywhere else in the article, and the lede is supposed to summarize the major points of the article. Furthermore, It describes a problem with a particular type of electric propulsion design (one powered by nuclear reactor) for a specific application. If allowed to remain it will be the only comment of such specificity in the lede. Ledes are not for very specific points nor for material not mentioned elsewhere in the article. Even if this point was made in the article body it still shouldn't be copied to the lede. The lede already notes that thrust from electric thrusters is very low. At most this could be followed by "and are therefore unsuitable for some applications", or some such.
Two: I will have a tough time agreeing that a Geocities page that purports to be a summary of a meeting of the British Interplanetary Society held in 1973 is a reliable source for anything. It is (or, more properly, was), after all, a self-published source with no editorial oversight. The BIS is however not an ephemeral group; it ought to be possible for someone to lay eyes on a hardcopy of the "Starship Study Progress Report". An author credit, publication date, etc., would be helpful. But even then, WP can only report that forty years ago, the BIS concluded that "Electrically powered spacecraft propulsion with a nuclear reactor is unsuitable for interstellar flight for a reasonable period". WP cannot report that claim as if it were established fact. (And I'm not sure what significance a conclusion from forty years ago has, anyway. Granted that F=ma, mv = m'v', etc., don't change, but nuclear electric generators for spacecraft produce a whole lot more W/kg than they did in 1973.)
Three: There is the matter of balance. An impression should not be left that nuclear-powered electric drive would be unsuitable for all interstellar missions. NASA, for example, concluded that a long-duration unmanned probe could be powered by an RTG. If this study is cited with the apparent conclusion then other studies giving different conclusions (perhaps for different circumstances) should also be found and cited.
Four: Even after finding a proper reference and citing the report's conclusion correctly, and citing other, related reports, it still won't belong in the lede. I see V. has added similar text to the ledes of two other related articles. It doesn't belong there either.
Five: Per WP:BRD, Vyacheslav84 (talk · contribs) was Bold, his edit was Reverted, and we are now Discussing it. Vyacheslav84 (talk · contribs) should not re-add his edit until consensus in support is reached here. Jeh (talk) 09:08, 2 March 2013 (UTC)
- For example, the controlled fusion engine and the nuclear electric systems all have a very high mass associated with the hardware required to implement the system and hence the achievable acceleration is very low. This results in having to spend centuries just accelerating to the desired velocity - which is clearly not satisfactory for the present study. Vyacheslav84 (talk) 11:12, 2 March 2013 (UTC)
- Ok, you copied from the source you already gave the specific sentence that supports your text. But there was not a question about whether your source supported your text. You have not answered any of the points above; they still stand. Jeh (talk) 14:32, 2 March 2013 (UTC)
- One: At most this could be followed by "and are therefore unsuitable for some applications", or some such. I agree with the editing form "because of low traction use Electrically powered spacecraft propulsion for interstellar flight would require hundreds of years to ramp up to speed" Vyacheslav84 (talk) 15:16, 2 March 2013 (UTC)
- Wikipedia talk:WikiProject Astronomy#I am looking for the original Vyacheslav84 (talk) 15:58, 2 March 2013 (UTC)
- That phrasing is better... but anything that specific to a particular use still would not belong in the lede. Particularly as nobody is seriously planning any interstellar flights anyway. That makes this point just about the least important thing that could be in the entire article, let alone the lede. Looking for the original is good, but lack of a reliable source for the reference is far from the only problem with your edit. Jeh (talk) 21:19, 2 March 2013 (UTC)
- Wikipedia talk:WikiProject Astronomy#I am looking for the original Vyacheslav84 (talk) 15:58, 2 March 2013 (UTC)
- One: At most this could be followed by "and are therefore unsuitable for some applications", or some such. I agree with the editing form "because of low traction use Electrically powered spacecraft propulsion for interstellar flight would require hundreds of years to ramp up to speed" Vyacheslav84 (talk) 15:16, 2 March 2013 (UTC)
- Ok, you copied from the source you already gave the specific sentence that supports your text. But there was not a question about whether your source supported your text. You have not answered any of the points above; they still stand. Jeh (talk) 14:32, 2 March 2013 (UTC)
«In the world of science» № 5 2009 pp. 34-42. Edgar Chueyri. A new dawn of electric rocket...Today's most advanced plasma thrusters dV can provide up to 100 km / s. This is sufficient for the flight to the external planets in a reasonable time.. external planets Solar System, but not for interstellar flight. Vyacheslav84 (talk) 15:30, 10 March 2013 (UTC)
- That's a fine reference for exactly what it says. But to then draw a conclusion that any electrically powered spacecraft propulsion ever will always be insufficient for interstellar flight would be original research on your part, and that is not suitable for inclusion in Wikipedia, regardless of how correct or defensible it is. Jeh (talk) 02:03, 15 March 2013 (UTC)
http://www.bis-space.com/ - though my English is not enough to search for the desired article. Can you help find it? Vyacheslav84 (talk) 07:20, 15 March 2013 (UTC)
- I tried several obvious searches, like "Starship Study Progress Report", "Daedulus", etc., and couldn't find it. I don't think their online material goes back to 1973. In any case, the quote you're trying to use as a reference says
"which is clearly not satisfactory for the present study"
- (emphasis added.) "Present", of course, was 1973. You cannot generalize from that to "for all interstellar flights now and in the future." It's already been 40 years. A much more current reference would be far better. Jeh (talk) 08:03, 15 March 2013 (UTC)
Modern models Electrically powered spacecraft propulsion suitable for flights to the external planets Solar System, but this would require nuclear energy[2].
Do you agree? Vyacheslav84 (talk) 08:39, 15 March 2013 (UTC)
- "Do I agree" with what? Jeh (talk) 09:16, 15 March 2013 (UTC)
- write in article "Modern models Electrically powered spacecraft propulsion suitable for flights to the external planets Solar System, but this would require nuclear energy[3]." Vyacheslav84 (talk) 09:26, 15 March 2013 (UTC)
- http://go2starss.narod.ru/pub/E013_IZRL.html - can somehow be put together with the source of interstellar flight. Vyacheslav84 (talk) 18:23, 17 March 2013 (UTC)
- Look... this stuff still does not belong in the lede. Certainly not immediately following the first sentence. This article needs something like a "characteristics and applications" section, or maybe two separate sections, and your material about limitations on use for interstellar flight should go there.
- However, I also notice that we have lots of other articles covering specific types of electric thrusters that have much more information, and some of them are not even linked from here. The collection looks like an uncoordinated mess and I just don't have time to start trying to rationalize it now. Accordingly I'm withdrawing from this discussion for the nonce. I am, however, going to ask the people at Wikiproject: Spaceflight to take a look at the collection; they have more expertise than I in the field and probably know of several other related articles that I've missed. Jeh (talk) 09:56, 19 March 2013 (UTC)
- I've restored an earlier, more idiomatic, version of the lead with some copyediting for wordiness. Fuel oil traction will not get us to the stars. --Wtshymanski (talk) 14:14, 19 March 2013 (UTC)
- Or rather you just delete information from an authoritative source. And on the subject of the article. And completely. Congratulations - that is Wikipedia and should be written: complete removal of the information. Can be proud of: you have won and I have removed all of my contribution to this article. Vyacheslav84 (talk) 17:12, 24 March 2013 (UTC)
- Of course, I do not justify the conduct of Wtshymanski and Jeh, but Vyacheslav84 made two serious errors. First, one should not link to Russian translations of originally English articles. Second, insertion of Russian spelling mistakes such as «способоны» into a machine translator leads to a garbage output which unlikely can be fixed without a knowledge of Russian. Forth-and-back transcriptions of proper names also make mistakes, which must be fixed manually. Use machine translators more careful, please, and in any case, link an original text in edit summary. Incnis Mrsi (talk) 08:08, 27 March 2013 (UTC)
Wtshymanski’s repeated attempts to smash several uncontroversial typography and link fixes are an “interesting” tool to force me to start negotiations, but it worked for this time. So, who (except for Wtshymanski himself) does object against disputed pieces of information, against which exactly, and why? Incnis Mrsi (talk) 19:56, 2 April 2013 (UTC)
- Hyphen-twiddling is one of our main occupations here on Jimbo's nightmare but that's not what I object to. Why smother a perfectly clear opening paragraph with prolix expansions? Bang away at all the em-dashes and en-dashes you want, but why make the opening paragraph redundant and wordy? At least we're not making diesel traction to the stars any more. --Wtshymanski (talk) 20:56, 2 April 2013 (UTC)
- I am not satisfied with this explanation. The information is topical and referenced, it rightfully belongs to the article, does not matter to the lead or not. Given current structure of the article, the lead is not bloated to such extent that its shortening became a necessity. Incnis Mrsi (talk) 21:02, 2 April 2013 (UTC)
- Per WP:LEDE, the lede is supposed to summarize the article. It should not contain anything significant that is not explained more fully in the rest of the article. I do not understand why you don't get this. Jeh (talk) 04:52, 3 April 2013 (UTC)
- Where does the article (in Wtshymanski’s revisions) explain lower specific force compared to the traditional space propulsion? Incnis Mrsi (talk) 05:41, 3 April 2013 (UTC)
- I never said W's version was perfect. Just that V's version is intolerable, about six ways from zero. Jeh (talk) 07:10, 3 April 2013 (UTC)
- Where does the article (in Wtshymanski’s revisions) explain lower specific force compared to the traditional space propulsion? Incnis Mrsi (talk) 05:41, 3 April 2013 (UTC)
- Per WP:LEDE, the lede is supposed to summarize the article. It should not contain anything significant that is not explained more fully in the rest of the article. I do not understand why you don't get this. Jeh (talk) 04:52, 3 April 2013 (UTC)
- I am not satisfied with this explanation. The information is topical and referenced, it rightfully belongs to the article, does not matter to the lead or not. Given current structure of the article, the lead is not bloated to such extent that its shortening became a necessity. Incnis Mrsi (talk) 21:02, 2 April 2013 (UTC)
References
Content degradations and misleading edit summary of Wtshymanski
[edit]- The summary says: “replace grotesque ugly low content lead with one that has some content and says the same things” – it’s a lie, the lead was not low-content, and replacement (actually, an act of edit warring) did not always improve it:
- internal link electric power removed without compensation
- internal link magnetosphere removed without compensation
- “thrust is weaker” does not offer any explanation, but non-specific link “orders of magnitude” was injected
- “becuase” [1]
- “the spacecraft mostly follows an inertial trajectory” (were: “most of its flight time the spacecraft almost follows an inertial trajectory”, which is longer, but correct)
- the same edit removed crucially important references to “gravity well” and “orbiting”
Does somebody (except Wtshymanski himself) object against fixing all these degradations? Incnis Mrsi (talk) 17:29, 4 April 2013 (UTC)
Technical Error: bad definition of specific impulse in intro
[edit]- intro says "Electric thrusters typically offer much higher thrust duration per unit weight of propellant than chemical rockets". This is not technically correct. They offer much higher specific impulse, which is much higher total impulse per unit weight of propellant. Total impulse is equal to the magnitude of the thrust multiplied by the thrust duration. Thrust duration in and of itself is not meaningful unless you specify the thrust magnitude.
Bottom line: the phrase "higher thrust duration per unit weight" is not correct. I recommend it be changed back to simply "specific impulse", which is technically correct. Any objections? Marstimrdad —Preceding undated comment added 04:03, 24 October 2013 (UTC)
Geoffrey Landis
[edit][2] - Geoffrey A. Landis: Laser-powered Interstellar Probe Vyacheslav84 (talk) 05:08, 16 November 2013 (UTC)
question
[edit]There is a proposal to make in the History section Electrically powered spacecraft propulsion such a proposal "Electrically powered spacecraft propulsion with a nuclear reactor considered\discussed for interstellar Project Daedalus and was rejected because of small acceleration and big time travel. Title: Project Daedalus. Authors: Bond, A.; Martin, A. R. Publication: Journal of the British Interplanetary Society Supplement, p. S5-S7 Publication Date: 00/1978 Origin: ARI ARI Keywords: Miscellanea, Philosophical Aspects, Extraterrestrial Life Comment: A & AA ID. AAA021.015.025 Bibliographic Code: 1978JBIS ... 31S ... 5B " Do you agree? Vyacheslav84 (talk) 06:17, 28 November 2013 (UTC)
- http://scholar.google.ru/scholar?lr=lang_ru&q=Project+Daedalus+&hl=ru&as_sdt=0,5 - № 6 [DOC] 22. PROJECT DAEDALUS: THE PROPULSION SYSTEM Part 1; Theoretical considerations and calculations - "2. REVIEW OF ADVANCED PROPULSION SYSTEMS A survey of most of the propulsion systems which may be capable of interstellar flight application has been given by Bond [9]. Here we briefly note some of the reasons for the choice of system for Project Daedalus. The nuclear-electric system [10, 11] where electrical energy is produced by a nuclear-powered generator and used to accelerate a working fluid, has a very high mass associated with the hardware required to implement the system, and hence the achievable acceleration is very low. This results in a long acceleration time before the desired final velocity is reached, and long journey times [12]." --Vyacheslav84 (talk) 06:50, 28 November 2013 (UTC)
Electric Propulsion use more often at Earth than in deep space
[edit]The claim that electric propulsion "...works best for deep space missions." is demonstrably incorrect since reference 5 lists over 200 spacecraft that use electric propulsion in Earth orbit. That statement should be removed from the introduction, since it contradicts the sentence just 2 lines below low. (see W. Andrew Hoskins et al. "30 Years of Electric Propulsion Flight Experience at Aerojet Rocketdyne", Paper IEPC-2013-439, 33rd International Electric Propulsion Conference, Washington DC, October 2013. http://www.iepc2013.org/get?id=439 18:37, 8 February 2014 (UTC)
- "...works best for deep space missions." - Compared to chemical rockets. In Earth orbit used for orbit control, but not flight.
90.189.106.180 (talk) 05:14, 13 February 2014 (UTC)
- 1) electric propulsion is used not only for orbit control, but also for orbit raising in Earth orbit. That certainly counts as flight (as does orbit control, IMHO). 2) "works best compared to chemical rockets" contains a value judgement that really doesn't belong in an objective article. "Best" depends on your application. Mars landers, for example, don't' use electric propulsion but they are deep space missions. The term "best" really doesn't make sense in this context.
Marstimrdad (talk) 19:26, 14 February 2014 (UTC)
- Electric propulsion can achieve high speeds over long periods сompared to chemical rockets - Choueiri, Edgar Y. (2009) New dawn of electric rocket Scientific American 300, 58–65 doi:10.1038/scientificamerican0209-58 --90.189.106.180 (talk) 02:36, 15 February 2014 (UTC)
- Eddie's statement is objectively true; electric propulsion can achieve high speeds [high delta-V] over long periods compared to chemical rockets. However, this does not mean that electric propulsion is "best". "Best" is a subjective term, and whether electric propulsion is best for a given mission depends on the total delta-V you require, the power sources available, how much time you have to travel, your thrust to weight ratio, etc. etc. I recommend deleting the entire sentence reading "Electric propulsion can achieve high speeds over long periods and thus works best for deep space missions compared with chemical rocket." It is basically saying the same thing as the that the system operates at higher specific impulse. Keep to objective statements and avoid the judgment of "best" or not. Marstimrdad (talk) 00:27, 16 February 2014 (UTC)
User Marstimrdad and his change in article
[edit][3] - But trips to the outer planets of the solar system would generally require nuclear power sources. A large, heavy craft would need a nuclear reactor, but a smaller, lighter one might get by with a thermoelectric power-generation device heated by the decay of radioisotopes...So far the most advanced designs could impart a delta-v of 100 km/s much too slow to take a spacecraft to the far-off stars but plenty enough to visit the outer planets in a reasonable amount of time. Vyacheslav84 (talk) 02:32, 2 September 2014 (UTC)
• The statement that "modern types of electrically power spacecraft propulsion have Delta-V to 100 km/s..." does not match what is said in the citation. The citation says that "advanced *designs*" could have a delta-v of 100 km/s. But those designs have not yet been built or flown - they are future spacecraft. Modern spacecraft have much, much less delta-V capability. The highest delta-V spacecraft that has actually been flown is the Dawn spacecraft, which only passed 4.3 km/s in 2010 (see: http://www.jpl.nasa.gov/news/news.php?release=2010-192). That is why the statement was changed to say that "in the future, the most advanced thrusters...". Alternately, you could say that some designs for future spacecraft would allow a delta-V of 100 km/s. But modern, currently existing spacecraft, come no where close to 100 km/s. Marstimrdad (talk) 17:38, 3 September 2014 (UTC)
- I have a question to removal this part of the text "...(with nuclear power), but are unsuitable for flight to extrasolar stars." Vyacheslav84 (talk) 00:52, 4 September 2014 (UTC)
- Ok to keep that statement, but I cleaned up the wording to make it grammatically correct. The next sentence, about lasers for interstellar travel, is also grammatically incorrect, but I have not fixed it.Marstimrdad (talk) 04:17, 4 September 2014 (UTC)
- Ok. "The next sentence, about lasers for interstellar travel, is also grammatically incorrect, but I have not fixed it." - Wikipedia:Be bold, but without deletion of text. Vyacheslav84 (talk) 05:48, 4 September 2014 (UTC)
Requested move 09 February 2015
[edit]- The following is a closed discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.
The result of the proposal was not moved per discussion. The redirect has been created.--Fuhghettaboutit (talk) 13:01, 17 February 2015 (UTC)
Electrically powered spacecraft propulsion → Electric rocket - Edgar Choueiri - Choueiri, Edgar Y. (2009) New dawn of electric rocket Scientific American 300, 58–65 doi:10.1038/scientificamerican0209-58 Vyacheslav84 (talk) 13:58, 9 February 2015 (UTC)
Survey
[edit]- Feel free to state your position on the renaming proposal by beginning a new line in this section with
*'''Support'''
oder*'''Oppose'''
, then sign your comment with~~~~
. Since polling is not a substitute for discussion, please explain your reasons, taking into account Wikipedia's policy on article titles.
- Oppose provisionally as per WP:AT. Primarily a rocket is used to help a vehicle escape from a planet (or to move a package of fireworks into an elevated position). The propulsion presented seems to relate to space flight. GregKaye 17:00, 9 February 2015 (UTC)
- Oppose not the term used anywhere except this SciAm article. Also, "rocket" (electrically driven reaction mass) isn't general enough for all types of electric propulsion, like tethers acting against a magnetic field. I wouldn't oppose an "Electric rocket" redirect, though. --IanOsgood (talk) 23:10, 9 February 2015 (UTC)
- Strong oppose changes the scope of the article. The article covers more than just rockets. If you want to split a subtopic article off, this is the wrong way to do it, as it would make the name of the article NOT in line with the scope of the content -- 70.51.200.101 (talk) 05:12, 11 February 2015 (UTC)
- Oppose Rockets are a subset and the most interesting techniques don't involve shoving mass overboard.--Wtshymanski (talk) 15:10, 11 February 2015 (UTC)
Discussion
[edit]Any additional comments:
- The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.
Specific Impulse
[edit]Something is wrong here. The article states:
- Performance of electrothermal systems in terms of specific impulse (Isp) is somewhat modest (500 to ~1000 seconds), but exceeds that of cold gas thrusters, monopropellant rockets, and even most bipropellant rockets.
Yet the article Liquid rocket propellant states (about bipropellants):
- The highest specific impulse chemistry ever test-fired in a rocket engine was lithium and fluorine, with hydrogen added to improve the exhaust thermodynamics [...]. The combination delivered 542 s specific impulse in a vacuum [...].
This does not add up. Either the specific impulse values of the electrothermal systems is misstated, or it is anything but "modest in terms of specific impulse" (being on par with the most effective bipropellant to being almost twice as effective). -- 145.228.61.5 (talk) 08:14, 15 October 2015 (UTC)
Ion thrusters used by Soviet Zond robotic spacecraft
[edit]I have recently come across references that indicate the the Soviet Zond spacecraft all used experimental ion thrusters for attitude control, including this reference from NASA on Zond 1. This reference gives further details, including “Its new ion thrusters were also tested but were found to operate erratically, possibly due to the loss of pressure in the orbital compartment where the thrusters’ control systems were located.” As the Zond 1 mission predates the SERT-1 test I believe the wording “The first demonstration of electric propulsion was an ion engine carried on board the NASA SERT-1” needs to be modified. Was thinking of stating that the first test was Zond 1 and the first successful demonstration was SERT-1. This logic could also be used in other articles that state that SERT-1 was the first demonstation in space. Thoughts? Ilenart626 (talk) 18:00, 8 February 2024 (UTC)
- Sounds reasonable to me, though I would note that the drewexmachina.com source probably would not pass muster, as it's a 'blog' of sorts - regardless of the author's obvious subject-matter expertise. But the rest of it sound perfectly reasonable. cheers. anastrophe, an editor he is. 04:15, 9 February 2024 (UTC)
- This is the first time I have come across Drewexmachina and for a amateur website it appears to have some decent information. Note that for Zond 1 the site includes a list of references. However I take your point and in addition to the NASA reference a quick review identified quite a few other references ie 1 2. Drewexmachina‘s references also included Boris Chertok, Rockets and People Volume III so any changes I make will include other references. Thanks for your comments. Ilenart626 (talk) 10:40, 9 February 2024 (UTC)
- Sounds reasonable to me, though I would note that the drewexmachina.com source probably would not pass muster, as it's a 'blog' of sorts - regardless of the author's obvious subject-matter expertise. But the rest of it sound perfectly reasonable. cheers. anastrophe, an editor he is. 04:15, 9 February 2024 (UTC)