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I slightly tweaked the lead section of the article. I looked in at least six different reference works including four dictionaries and two encyclopedias, and nobody defined outer space as excluding the atmospheres of other planets. So I rewrote the lead of the article to reflect the same definition that I found everywhere, namely that outer space is that space which lies beyond Earth's atmosphere. Thanks, Lighthumormonger (talk)21:24, 13 June 2024 (UTC)[reply]
Your revision amounted to "Space is space", a circular definition. The original was better. For example, the New World Encyclopedia says,"Outer space (often called space) consists of the relatively empty regions of the universe outside the atmospheres of celestial bodies." There isn't a consensus legal definition, but the current one seems sufficiently clear.Praemonitus (talk)01:24, 15 June 2024 (UTC)[reply]
Yes, Outer space is definitely Outer space. The seemingly novel interpretation that you have shown me from the New World Encyclopedia appears to me to be a minority opinion of a very small group of people. Also, you haven't cited the source of this information. "Flat Earth Theory" may be listed in some off-brand encyclopedia site too. I have made the same mistake many times in my edits of Wikipedia, of thinking I have found a reliable source when after another editor asked me about it, I then found that the source was not as reliable as I had first thought.
Could you somehow please show me that this is a majority opinion? By doing a simple Google search on the definition of outer space and reading the first six definitions that pop up, all of those six definitions were consistent with the one I used and none of them in anyway appeared to reflect the views of the New World Encyclopedia where say the"atmosphere of Mars at Mars's surface" would not be considered as a part of outer space. Please take a look at this link and see what I mean:
Oh I forgot to mention the Wikipedia result which did happen to match what you were saying, but that was the only one. Please help me here. Yes Encyclopedias are usually good reference sources, but they still need to be compared to other sources. Do you still think that the views of the New World Encyclopedia are the majority view? Thanks, Lighthumormonger (talk)18:11, 15 June 2024 (UTC)[reply]
Well my point is that your statement leaves "space" undefined. A dictionary definition is, "a continuous area or expanse which is free, available, or unoccupied." Ergo, space can be taken as an unoccupied area or expanse. Yes? I prefer the latter term as it is more suggestive of great distances. It follows then that space is an (empty) expanse that lies between non-Earthly bodies and their atmosphere. The point about Mars' atmosphere seems like a trivial nit, considering how vast the cosmos is compared to that planet. But if we wanted to drill down on that, on Earth the Kármán line is used to define the start of space based in terms of atmospheric powered flight, something that has been demonstrated on Mars. Hence, there's an argument to be made that the surface of Mars is not outer space. In that case we need a reliable source that says otherwise.Praemonitus (talk)23:32, 15 June 2024 (UTC)[reply]
Yes, that is a dictionary of "Space." But how do all of the major dictionary's define "Outer Space?" I can see the possibility that if we ever might find another planet that doesn't require a space suit to survive in, then maybe people might call that something like an "Earth-like atmosphere," and not "outer space," but that is a long ways off, and unlikely in our own lifetimes. I believe that may be why all of the major dictionaries define "Outer Space" as simply that which lies beyond Earth's atmosphere." Aren't we supposed to generally go with "majority views" in WP? Lighthumormonger (talk)04:59, 16 June 2024 (UTC)[reply]
Circling back once again. A dictionary says outer space is a type of space. Space has multiple meanings, so the reader then flips to the definition of space to find out what that means in particular. Both parts are necessary to properly define outer space. For example, Merriam-Webster states, "The meaning of OUTER SPACE is space immediately outside the earth's atmosphere". Again, what is space? The current first sentence is both comprehensive and correct; I see no reason to change it. It's been reviewed and massaged many times by many readers. I consider it a consensus as such.Praemonitus (talk)05:09, 16 June 2024 (UTC)[reply]
So you believe that Wikipedia shoulddisagree with the common wisdom of most dictionaries in how it defines "Outer Space," and that our "disagreement" with the common wisdom of most dictionaries should not be supported by any cite? (I still haven't seen a single cite in the article supporting your argument here.) Lighthumormonger (talk)05:19, 16 June 2024 (UTC)[reply]
WP:NOTDICTIONARY. The statement properly consolidates the typical dictionary definition of "outer space" with the applicable definition of "space". There is no conflict in my mind. Anyway, no I don't find this particularly stimulating; merely tedious and repetitive.Praemonitus (talk)05:27, 16 June 2024 (UTC)[reply]
You still haven't answered any of my questions here. I find your unwillingness to edit a view into WP that is not supported by any major dictionaries, and to write such a view without being able to provide any supporting citE, and in fact to delete the common dictionary view that was cited, and to replace it with your own uncited material, to be a bit "mysterious" myself. Please either support your recent deletions of this with a cite of a major work, or else let me put it back. Goodnight my friend.
Outer space -- "space immediately outside the earth's atmosphere"
Space -- "physical spaceindependent of what occupies it"
Put those together and you get: "physical space independent of what occupies it, immediately outside the earth's atmosphere".
Per Wictionary: "Any region of space beyond limits determined with reference to boundaries of a celestial system or body, especially the region of space immediately beyond Earth's atmosphere; sometimes, space beyond Earth's solar system."
Sure, the term gets used for multiple purposes, and there is no actual legal definition of "outer space". But maybe that's a good thing. The current statement is what is discussed by the article.Praemonitus (talk)05:46, 16 June 2024 (UTC)[reply]
I'll add that it used to say, "Outer space, commonly shortened to space, is the expanse that exists beyond Earth and its atmosphere and between celestial bodies." From that it was shortened to its present form.Praemonitus (talk)14:07, 16 June 2024 (UTC)[reply]
I apologize. When I was writing last night I should've been clearer. Could you please put your cites into the article itself? The posting of uncited views in an article sometimes looks to me as if it might be opinion stated as fact. Thanks, Lighthumormonger (talk)14:53, 16 June 2024 (UTC)[reply]
Sure. I'm thinking now that it may make sense (as a compromise) to flip the statement back to that older form, then add a note referencing the Merriam-Webster definitions to add it some weight. Would that make sense? The current form is just a semi-consolidated version, so the old one is still valid.Praemonitus (talk)17:29, 16 June 2024 (UTC)[reply]
That sounds like it would probably work. Please feel free to redo it as you are suggesting and I'll probably finally "shut my yap." Thank you my friend, Lighthumormonger (talk)17:56, 16 June 2024 (UTC)[reply]
Hi again Praemonitus, (@Praemonitus:) Thank you for the very helpful edit. Without changing your edit, I added what I consider to be supporting material. I'm hoping you might agree with the intentions of my edit. If you could find a reliable cite that defines other "celestial bodies with atmospheres" asnot a part of outer-space, and then if you could please cite this source in the lead, then of course I would be happy if you reverted my last edit. Otherwise I'm hoping that you might please not revert it? Thank you kindly my friend, Lighthumormonger (talk)05:48, 18 June 2024 (UTC)[reply]
I think we should avoid the topic because it isn't well defined outside of the Earth, and seems to me to be drifting intoWP:OR. For now we should just leave it vague.Praemonitus (talk)14:13, 18 June 2024 (UTC)[reply]
I just a reread the way you defined it, and you're right. You reworded it in a sort of a "vague" way that I finally accept. Thank you my friend, Lighthumormonger (talk)15:49, 18 June 2024 (UTC)[reply]
Hi again Praemonitus, I just put a very minor "tweak" on the second sentence of the lead, but if you want to revert my edit, that's OK with me. Thanks, Lighthumormonger (talk)04:20, 20 June 2024 (UTC)[reply]
@Praemonitus @Nsae CompThis sentence was recently added without a source then marked as citation needed:
Cosmic radiation in low Earth orbit is reduced due to being inside of the Van Allen belt, the lowest radiation belt of Earth's shielding magnetosphere.
I agree that new additions should be properly sourced. In this case it seemed like the wording is redundant with what follows, so I'm not sure it was an improvement.Praemonitus (talk)17:27, 2 January 2025 (UTC)[reply]
I am sorry the use of "inside" was wrong, I meant "below" the inner V.A. belt, as of course the V.A. belt has high radiation. Sorry for that. But I dont see a problem with the paragraph as a whole. Citation about low Earth orbit and its bordering of the V.A. belt isnt a problem, e.g.:[1].Nsae Comp (talk)01:40, 3 January 2025 (UTC)[reply]
Actually no, I don't think it does properly cite the statement. At least not the part I can access. All it says is that the Van Allen belt has a higher level of radiation, which can impact satellite safety.Praemonitus (talk)02:22, 3 January 2025 (UTC)[reply]
Here's your statement: "Cosmic radiation in low Earth orbit isreduced due to being below the inner Van Allen belt, the lowest radiation belt of Earth's shielding magnetosphere." Where does the source state that the Van Allen belt reduces cosmic radiation? All I see is that the belt shows a higher radiation level than LEO. Your conclusion does not follow. All the source implies is that radiation accumulates in the belt.Praemonitus (talk)03:18, 4 January 2025 (UTC)[reply]
Same is true for the para you took out: none is controversial and it is only a basic introducing statement, finding a reference shouldnt be a problem as far as I can see:
Living in outer space is shaped by the characteristic environment of outer space, particularly itsmicrogravity (producingweightlessness) and its nearperfect vacuum (supplying few and producing unhindered exposure toradiation and material from far away). Radiation is prevalent in outer space particularly beyond shieldingmagnetospheres, being one of the main challenges of sustained human spaceflight beyondlow Earth orbit.
I agree that a short intro paragraph does not necessarily need citations, but this paragraph does much more and in my opinion it is controversial. The paragraph introduces contradictions (gravity <-> weightlessness) and ambiguous quantifications ("near perfect", "prevalent", "main challenges"). An introductory paragraph should be a completely neutral outline:
Living in outer space is shaped by weightlessness, lack of atmosphere, and exposure to radiation.
Thank you for engaging about the content. Now I understand what you see controversial. I can relate. While I think the issues are not unsolvable I am going with your concise version, because with that the chapter doesnt right away start with the possibility of extremophiles living in space.Nsae Comp (talk)19:57, 3 January 2025 (UTC)[reply]
References
^Kohani, Saeid; Zong, Peng (2018). "LEO constellation design for regional coverage based on the safety of van allen belt radiation".Journal of Space Safety Engineering.5 (3–4):203–208.doi:10.1016/j.jsse.2018.10.001.
The inner Van Allen radiation belt encompasses a significant part of low earth orbit, so the claim that "Cosmic radiation in low Earth orbit is reduced due to being below the inner Van Allen belt" is invalid and should be removed. Cf. D. N. Baker et al (2017).[1]Praemonitus (talk)00:03, 5 January 2025 (UTC)[reply]
The Wikipedia article forlow Earth orbit states that it extends past 800 km, while the van Allen radiation belts drop down to 640 km. In the South Atlantic anomaly, the belt drops down to 200 km. Thus they overlap.Praemonitus (talk)18:05, 9 March 2025 (UTC)[reply]
Okay, well it need some edits. The statement "accelerate beyondsub-orbital spaceflight" is redundant with "achieveorbital spaceflight". The segment stating, "accelerate equal or beyond thecentripetal acceleration due to gravity" doesn't make sense. It's the tangential velocity (in conjunction with gravity) that produces the centrifugal acceleration. The current wording is more accurate.Praemonitus (talk)15:50, 11 March 2025 (UTC)[reply]
Neither your proposal nor the current jargon-y first sentence
A spacecraft enters Earth orbit when its centripetal acceleration due to gravity is less than or equal to the centrifugal acceleration due to the horizontal component of its velocity.
gets across the essential character of orbit. Spacecraft continually fall due to gravity: to orbit requires a specific speed perpendicular to the force of gravity, a speed so high that the spacecraft falls around the curve of its orbit. This speed is so high it cannot be maintained in Earth's atmosphere. We need sources that give this concept.Johnjbarton (talk)15:52, 11 March 2025 (UTC)[reply]
When a launched rocket terminates its thrust, it is going to follow an arc-liketrajectory back toward the ground, under the influence of the Earth'sgravitational force. Atorbital velocity, the curvature of this arc can be set to parallel the curvature of the planet underneath, and the spacecraft will be in orbit. That is, the spacecraft enters Earth orbit when itscentripetal acceleration due to gravity is less than or equal to thecentrifugal acceleration due to the tangential component of its velocity.
I like part of your proposal. I think invoking a fictitious force is confusing and unnecessary.
When rocket is launched its thrust must both counter gravity and accelerate it toorbital velocity. When the rocket terminates its thrust, it is going to follow an arc-liketrajectory back toward the ground under the influence of the Earth'sgravitational force. In orbit, the curvature of this arc parallels the curvature of the planet underneath. That is, a spacecraft successfully enters Earth orbit when itsacceleration due to gravity pushes the craft down just enough to prevent its momentum from carrying it off into outer space. (https://www.nesdis.noaa.gov/news/why-dont-satellites-fall-out-of-the-sky)
I don't agree with your first sentence because a rocket launch does not necessarily mean it is going to reach orbital velocity. The point was to present the general case of the rocket following an arc, followed by the special case of achieving orbital velocity.Praemonitus (talk)00:51, 12 March 2025 (UTC)[reply]
", the curvature of this arc will tend to parallel the curvature of the planet underneath." is that true? Pertubation is a component, but the curvature of the planet isnt the factor, it is the distribution of its mass, its density distribution.Nsae Comp (talk)18:49, 15 March 2025 (UTC)[reply]
All it's saying is the orbit doesn't plummet into the ground or fly off into space. It's a simple explanation, which is what you want for an intro. No need to over think it. (I suppose it could say "...will tend to follow the curve..." so the wording is more clearly simplified.)
Or we could de-nerdify it even further and just say, "For a circular orbit, the curvature of this arc will parallel the curve of the planet underneath."Praemonitus (talk)20:09, 15 March 2025 (UTC)[reply]
I have several issues with this version. Firstly what is it for anyway? Is it to describe Earth orbit or Human access to it? I more and more think its fine to take the whole para out and start right away with the second. Otherwise I have a revised proposal very much shortened:"To reach Earth orbit from the surface a spacecraft must be accelerated to orbital speed."
or a longer more precise proposal including non-trivial components like drag and perturbation, but most importantly one that does not say that orbits are curved like the planets below, that is back to ancient understanding of orbits, closed orbits are mostly elliptical, plus merging the sentence about leaving Earth orbit and falling toward Earth by focusing on falling at a speed lower than escape velocity:"To reach Earth orbit from the surface a spacecraft must be accelerated to orbital speed. The spacecraft successfully enters orbit when it does not reachescape velocity and falls toward Earth due to its gravitational pull, but at the same time does not intersect and reach the surface. Therefore an achieved orbit takes the spaceship on a flightpath which follows a closed curved trajectory under the influence of the Earth's gravitational force. Subsequently orbits are maintained bystation keeping, countering orbital degradation in the presence of drag andperturbation."Nsae Comp (talk)02:26, 16 March 2025 (UTC)[reply]
No, that's far too much detail for this page. The article is about outer space so it should focus on that, providing just enough detail to explain in simple terms how a spacecraft achieves orbit. The reader can go to the Earth orbit for more details.Praemonitus (talk)03:23, 16 March 2025 (UTC)[reply]
level-3 vital article is ratedGA-class on Wikipedia'scontent assessment scale.
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