The Atmosphere: Where Does It End

[Mr. Bambu]

What's the problem?
Making this thread on a whim after seeing calcs that rustle my feathers a little bit.

To make a long story short, I think we need to provide an official stance on the distance from the Earth to the edge of the atmosphere. The reason I think this is because calcs tend to use 10,000 kilometers (that's about 2.5% of the distance to the moon), which is the lower-end of the edge of the Exosphere, the outermost layer of the atmosphere that is formally recognized. There are a few problems with this, the greatest of which being that the exosphere, for all intents and purposes, is outer space: its sole role as a classification of the atmosphere is that it is where atoms that escape the actual atmosphere of Earth float about.

Satellites and even the International Space Station all rest in the layer below it, the Thermosphere, which is still widely regarded as being "outer space" for all intents and purposes. These are all beyond the point that is considered "space" by the vast majority of people. What this means is that calculations using "the atmosphere" as a phrase are often incorrect by a factor of 20-100, as they're using a vastly overestimated line that is for all intents and purposes indistinguishable from the area surrounding it.

What should we do?
I think the best solution is what @Jaften recommended when I raised my concerns with him and others elsewhere. He suggested the Kármán Line as the typically recognized edge-of-space, which exists 100 kilometers up and is used by international law to separate Earth from outer space. It is based upon the theoretical maximum height terrestrial flying vehicles (read: airplanes) can go, after which conditions become too difficult (read: space-like) to traverse.

Now, the "edge of space" is recognized as a fairly arbitrary term: there is no hard cut-off, rather it is a gradual loss of properties that define our atmosphere. The greatest distinctions, one feels, are the points at which properties are lost. The Karman Line represents some of these losses of characteristics of atmosphere. I think it is the best option, especially when compared to the oft-cited 10,000 kilometer figure.

So, thoughts, insights, all are appreciated. This is a calc group matter and so all CGMs have a voice here.

Tallies
Agree with 100km: 11 (Mr. Bambu, DMUA, Damage3245, Aguywhodoesthings, Migue79, SeijiSetto, TheRustyOne, AbaddonTheDisappointment, CloverDragon03, KLOL506, Flashlight237)

Disagree with 100km: 0

 

[DMUA]

I've used and approved for 100 KM for awhile now so I definitely agree with using that instead

 

[Jaften]

Specifically, at and above the Kármán line, aircraft have to travel faster than orbital speed to produce lift. This is because the atmosphere is so rarified at this height it's more accurately described as "scattered gas molecules" given it no longer acts much like a fluid. 99.99997% of the atmosphere is found below the Kármán line. It is for all intents and purposes "outer space".

 

[Mr. Bambu]

You'll all have to spare me the condemnations as I ping some of calc group just this once. I think this is an easily solvable matter with little controversy or heated discussion in its future.

@Armorchompy @M3X_2.0 @Agnaa @Damage3245 @Migue79 @CloverDragon03 @SeijiSetto @DemiiPowa @DemonGodMitchAubin @Therefir @AbaddonTheDisappointment @Aguywhodoesthings and @Psychomaster35 should be enough to get the ball rolling.

 

[Damage3245]

100 km works for me.

 

[Aguywhodoesthings]

i'm ok with 100km, that's what go with in calcs involving going to space already

 

[Migue79]

The new proposal is reasonable. But I have to ask… What kind of existing calcs use the erroneous 10,000 km figure? I hope it isn’t any cloud-related feats.

 

[SeijiSetto]

karman line (100km) goated

 

[TheRustyOne]

Using 100 km is far better, I fully support this.

 

[AbaddonTheDisappointment]

Yeah 100 km is fine by me

 

[CloverDragon03]

100 km looks good

 

[Mr. Bambu]

The new proposal is reasonable. But I have to ask… What kind of existing calcs use the erroneous 10,000 km figure? I hope it isn’t any cloud-related feats.

I was reminded of the issue here, which originally used the 10,000 km value. I've seen others but couldn't grab them now. It's not manipulative of the calculators- they search up the atmosphere and use the end, but by providing a policy, it makes everything much more reasonable.

Anywho, this seems unanimous with 9 votes. @Antvasima should probably speak on the matter before anything else but it seems like this has been accepted- when it gets applied, if you see a calc using the 10,000 km figure, just set 'em straight, luckily it's a fairly easy matter to adjust.

 

[KLOL506]

100 km for atmospheric limit is fine.

 

[Psychomaster35]

100 km should be fine to use as the new limit

 

[Antvasima]

I was reminded of the issue here, which originally used the 10,000 km value. I've seen others but couldn't grab them now. It's not manipulative of the calculators- they search up the atmosphere and use the end, but by providing a policy, it makes everything much more reasonable.

Anywho, this seems unanimous with 9 votes. @Antvasima should probably speak on the matter before anything else but it seems like this has been accepted- when it gets applied, if you see a calc using the 10,000 km figure, just set 'em straight, luckily it's a fairly easy matter to adjust.

This seems fine to me in that case. I usually try to not interfere when other staff members have greater expertise than I do regarding an issue.

 

[Mr. Bambu]

Excellent. This is accepted, then, but where to put the rule, and how to phrase it?

Barring making a new page on the subject, the best place I can think of is the Potential Energy section of the Calculations page. The policy can be phrased like so:

There are many instances where the term "atmosphere" is used as a measurement in fiction, often for when a creature or object enters or exits the area of Earth. For all intents and purposes, in these scenarios, our wiki recognizes 100 kilometers above the surface of the Earth to be the edge of the effective atmosphere of Earth, based on the Kármán Line. This figure is to be used in all calculations utilizing the atmosphere to determine distances.

 

[CloverDragon03]

I think that makes sense, specifically in the "In cases far away from the ground" section

 

[Antvasima]

Excellent. This is accepted, then, but where to put the rule, and how to phrase it?

Barring making a new page on the subject, the best place I can think of is the Potential Energy section of the Calculations page. The policy can be phrased like so:

@Agnaa @DontTalkDT @ImmortalDread

 

[ImmortalDread]

I don't believe the section that Bambu mentioned is the ideal place for its inclusion. The text implies (or at least informs us) about the tools or measurements we need to use in the case of pixel scaling (or measurement) in general when occurring to atmosphere cases.

Therefore, it should be mentioned in the pixel scaling section instead, since it is a measurement topic.

 

[Mr. Bambu]

This has literally nothing to do with pixel scaling.

 

[CloverDragon03]

I'm with Bambu. While theoretically, there may be times where you need that distance as a reference to pixel scale from, this isn't exactly the more prevalent use case for it. It's more generally just a reliable distance value to use, and one that's incredibly far away, making the section it's proposed to be used in more appropriate

 

[ImmortalDread]

Care to explain what exactly does the measurement has anything to do with potential energy? Besides, can you link the section, since I did not find it in the calculation page as you mentioned above.

Or is it this? Potential Gravitational Energy: Energy of falling Objects and Energy to lift Objects

 

[CloverDragon03]

This section

 

[ImmortalDread]

I am neutral. The way the text is phrased is meant to offer an accepted measurement technique for cases where the atmosphere is used as a tool to measure distance. In my opinion, it should be mentioned somewhere in the Calculation Guide under "Frequently Used Measuring Techniques."

You could create a new section or simply include a note under it. I mentioned "Pixelscaling" since it is also a "measuring stick," and I believe members intend to measure the distance from Earth to the edge of the atmosphere. Creating a subsection is also acceptable to me.

Additionally, the OP seems to mention using 10k meters as accepted procedure beforehand, while the section you referred to did not specify using the atmosphere for anything.

Pardon me, I am not a calculation expert, but the topic is about measurements. Nowhere in this formula does it require the distance; I see the radius of the planet + the object distance before it hits the ground being relevant here.

 

[Mr. Bambu]

I am neutral. The way the text is phrased is meant to offer an accepted measurement technique for cases where the atmosphere is used as a tool to measure distance. In my opinion, it should be mentioned somewhere in the Calculation Guide under "Frequently Used Measuring Techniques."

This isn't really a measuring technique. This is a measurement.

You could create a new section or simply include a note under it. I mentioned "Pixelscaling" since it is also a "measuring stick," and I believe members intend to measure the distance from Earth to the edge of the atmosphere. Creating a subsection is also acceptable to me.

Pixel scaling is not a measuring stick. It is a means of utilizing measuring sticks. This suggestion does not make sense.

Additionally, the OP seems to mention using 10k meters as accepted procedure beforehand, while the section you referred to did not specify using the atmosphere for anything.

It isn't. 10k meters is just a figure most people see on the internet. We have no firm policy on this yet.

 

[Antvasima]

So should a new section be created in our calculations page then, or is it better to place the section in another page instead?

 

[KLOL506]

Anywho, this seems unanimous with 9 votes.

Hey stinky where's my vote

 

[Mr. Bambu]

So should a new section be created in our calculations page then, or is it better to place the section in another page instead?

It may suit our purposes, if we were so inclined, to create a "Common Measurements" section on the Calculations Page, if we were to create a section at all. It would also be consistent: distance or size is probably the only thing we don't offer a set policy on.

If we were to make that, though, we would probably want to populate it with other general use measurements. Suppose a followup thread could be had, I think such a thing would similarly be basically unanimous.

Hey stinky where's my vote

the opinion of Assassin's Creed fans can be freely discarded (I forgot it)

 

[Flashlight237]

In regards to this, I find 100 km to be perfectly reasonable, but I should mention that at the same time, it doesn't cover the fact that the Thermosphere goes up to 690 km: https://en.wikipedia.org/wiki/Thermosphere

Going with the thermosphere because the exosphere sometimes gets disregarded in texts as part of the atmosphere while the thermosphere is more unanimous.

 

[KLOL506]

the opinion of Assassin's Creed fans can be freely discarded (I forgot it)

Fair point

 

[Mr. Bambu]

In regards to this, I find 100 km to be perfectly reasonable, but I should mention that at the same time, it doesn't cover the fact that the Thermosphere goes up to 690 km: https://en.wikipedia.org/wiki/Thermosphere

Going with the thermosphere because the exosphere sometimes gets disregarded in texts as part of the atmosphere while the thermosphere is more unanimous.

I don't see how it would be "more unanimous" when nobody's voted on it. I would back 100 km over that for the simple fact that the thermosphere is, too, very much "essentially space", such that the ISS and a good swathe of our satellites hang in that layer.

 

[Flashlight237]

I don't see how it would be "more unanimous" when nobody's voted on it. I would back 100 km over that for the simple fact that the thermosphere is, too, very much "essentially space", such that the ISS and a good swathe of our satellites hang in that layer.

You missed the context. By "more unanimous", I meant more unanimously accepted by schools and scientific publishings, not here on the wiki where our workings don't entirely align with what the books say (usually to my chagrin, of course). Also, the Karman line is really just covers the lower segment of the thermopshere, low enough to where we don't exactly cover the part of the thermosphere where things really get heated in the literal sense.

 

[Mr. Bambu]

You missed the context. By "more unanimous", I meant more unanimously accepted by schools and scientific publishings, not here on the wiki where our workings don't entirely align with what the books say (usually to my chagrin, of course). Also, the Karman line is really just covers the lower segment of the thermopshere, low enough to where we don't exactly cover the part of the thermosphere where things really get heated in the literal sense.

The thermosphere represents a portion of space with some properties of atmosphere bleeding into it, primarily temperatures. I don't think it's a good cutoff for our purposes.

 

[Flashlight237]

The thermosphere represents a portion of space with some properties of atmosphere bleeding into it, primarily temperatures. I don't think it's a good cutoff for our purposes.

Fair enough I suppose.

 

[ImmortalDread]

So should a new section be created in our calculations page then, or is it better to place the section in another page instead?

I don't mind a section for measurements to be created.

I am opposed to the idea that it should be replaced under potential energy.

 

[Antvasima]

It may suit our purposes, if we were so inclined, to create a "Common Measurements" section on the Calculations Page, if we were to create a section at all. It would also be consistent: distance or size is probably the only thing we don't offer a set policy on.

If we were to make that, though, we would probably want to populate it with other general use measurements. Suppose a followup thread could be had, I think such a thing would similarly be basically unanimous.

I think that seems perfectly reasonable.

I don't mind a section for measurements to be created.

I am opposed to the idea that it should be replaced under potential energy.

Agreed.

 

[Mr. Bambu]

Alright. If the purpose of this thread is shifted to creating a table for this, I can think of a few things to populate it- standard height of a human (and, for pixel scaling reasons, the height of a human head, which is more often cited than you may think), the height of a building story, distance to various celestial bodies on average.

I must be honest that I can't conjure a comprehensive table on a whim, so if other CGMs want to come up with stuff they can. Seems pointless to make a table that's practically empty.

 

[Dalesean027]

Bump

 

[Mr. Bambu]

All calc group members called here agreed, and nobody is providing measurements to supply a theoretical section on such a thing. No discussion has been pursued, so I will ask the CGMs: do you guys want a section on standard measurements for the wiki, or would you rather tack this particular measurement as a note on somewhere?

 

[Dalesean027]

All calc group members called here agreed, and nobody is providing measurements to supply a theoretical section on such a thing. No discussion has been pursued, so I will ask the CGMs: do you guys want a section on standard measurements for the wiki, or would you rather tack this particular measurement as a note on somewhere?

I assume this is common measurements for all things like

Average height of a man: 1.71m

The height of a storey: 4.3m

Storey - Wikipedia

en.m.wikipedia.org

Or the height of an average skyscrapper 100m

Skyscraper - Wikipedia

en.m.wikipedia.org

Height of space: 100km etc. Etc.?