Talk:1389: Surface Area

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FYI to whoever writes this: the Seattle reference is the Space Needle. 108.162.221.65 05:03, 2 July 2014 (UTC)

Uranus is larger than all of these combined. Of course, it isn't on this map because it is full of gas. 173.245.62.62 05:50, 2 July 2014 (UTC)

Just wondering... Does that mean, a spaceship could just fly trough Uranus? (No pun intended.) --141.101.75.20 07:16, 2 July 2014 (UTC)
It'd probably hurt. As an ice-giant, the interior of Uranus is mainly composed of ices and rock. Jupiter and Saturn have cores of liquid metallic hydrogen. Also, the rock/ice isn't considered the surface of Uranus, because most of the planet's mass lies outside the solid inner layers.) 103.22.201.239 09:28, 2 July 2014 (UTC) P.S. Even if it was only gas, a spaceship would probably find it hard to handle the temperature and pressure at the center of Uranus.
As the gas giants contain a solid core, why is it the surface of those cores not included in the drawing? Just like Earth, Mars and Venus, they are still just solid with a (very thick) atmosphere. GadgetViking (talk) 23:55, 2 July 2014 (UTC)
Because it is a core and not a surface. On Earth, for example, most of the planet's total mass lies below solid ground, which can be considered the surface of the planet. In gas giants, most of the planet's mass is gas and lies outside the solid layers. How can it be the surface of the planet when it doesn't include most of the planet's mass within it? Suggested reading:[1]103.22.201.239 11:03, 3 July 2014 (UTC)
If the spaceship has not braked enough down it would burn up in the atmosphere. If it has it would get stuck in the core of the planet, where it would eventually get crushed, as the pressure would be brutal way before reaching any rock or metallic hydrogen. Although I did like the first comment :-p Kynde (talk) 21:00, 2 July 2014 (UTC)

And of course the earth is not correctly displayed: we have water which - in most cases - is not solid. -- jesterchen 141.101.75.19 07:23, 2 July 2014 (UTC)

Water still has surface area. Edit: oh, I see what you mean now, from the title in the comic. I guess you have a point, but it's mainly there for comparison so it's not necessarily a mistake. --NeatNit (talk) 06:14, 2 July 2014 (UTC)
Under the water there is solid bottom --JakubNarebski (talk) 07:01, 2 July 2014 (UTC)
But then it is not "surface" anymore... but you two have a point. I focused mainly on the title, not the image text... So forget my comment :) -- jesterchen 141.101.75.19 09:12, 2 July 2014 (UTC)
Water indeed has a surface, while gas doesn't. 141.101.104.47 11:13, 2 July 2014 (UTC)Martin
See the current explain - just remove the water from earth, and the earth's surface area would still be almost as big. It is only 3-4 km (on both sides) out of 12,000 km in the diameter. There are also fluids on some of the rocky moons (Ice and then water beneath on Europe, Methane lakes on Titan etc.)Kynde (talk) 21:00, 2 July 2014 (UTC)

There is also small section named "All human skin" (between Earth and Titan)... if you think about thread and needle... ugh... --JakubNarebski (talk) 07:01, 2 July 2014 (UTC)

This is exactly the same as seen from the planets perspective. Kynde (talk) 21:00, 2 July 2014 (UTC)

This seems to be an island floating on something, maybe it's floating on the sun's plasma? --BelgianAtheist (talk) 08:24, 2 July 2014 (UTC)

Or a supercontinent with an ocean around (so not floating). As the whole thing is just 3-4 times larger than earth, it would not need a very big planet to support it - a surface area 9 times as big as the earth would be plenty of big enough to contain the entire map (including all the ocean in the square). So the radius would only need to be like 3 times as big as the Earth's. No need to use the Sun for this... ;-) Kynde (talk) 21:00, 2 July 2014 (UTC)

So, what's the area surrounding Earth's landmass? It's not named, or am I blind? 141.101.99.218 09:46, 2 July 2014 (UTC)

It is the rest of the Earth - that part which is covered by the Ocean Kynde (talk) 21:00, 2 July 2014 (UTC)

Don't think it is strictly accurate to say that earth is included 'for scale' -- surely it is included because it qualifies to be on the map. Otherwise it's a bit like saying that Belgium is included in maps of Europe 'for scale' (as 'the size of Belgium' is a well-known unit of land area as in 'Amazonian rainforest the size of Belgium is cut down every week') -- Devonian Earache

The size of Belium is also famous for its reference in the Doctor Who mini-episode "Time Crash" (see http://www.chakoteya.net/doctorwho/CIN2007.htm) Esp666 (talk) (please sign your comments with ~~~~)
Agree completely with the earth not included for scale. Although maybe the continents are - as there is no features on the other well known surfaces like the moon. Kynde (talk) 20:13, 3 July 2014 (UTC)

The map of Earth doesn't look like the Waterman Butterfly projection. If it did, the continents would be angled in toward each other, and Australia would be up in the corner. The only thing that is even similar is that Antarctica is shown in "normal" proportions rather than stretched across the bottom. Prometheusmmiv (talk) 11:41, 2 July 2014 (UTC)

But the map projection reference is very relevant as it is indeed as the Waterman keeping the relative sizes of the continents. And Randall is very in to this obvious from the comic. Thus included again Kynde (talk) 21:00, 2 July 2014 (UTC)

What's the area on the coast between Asteroids (1km+) and Triton? 108.162.222.50 11:44, 2 July 2014 (UTC)

Good question. Did he forget it or...? It is way to big to be his own asteroid Asteroid 4942 Munroe ;) And much smaller even than Vesta Kynde (talk) 21:00, 2 July 2014 (UTC)
I believe I have solved the puzzle - it must be the second largest moon of Neptune (next to the only other very large Neptune moon) and it fits with the size. See explain. Kynde (talk) 20:13, 3 July 2014 (UTC)

(My first contribution here!) About the Earth/water surface issue, I think Randall is talking about planets' surface, and then it counts both earth and water (like if it were a sphere) 173.245.52.173 12:31, 2 July 2014 (UTC)

I changed the explanation of the title text. The previous explanation, "all the matter in the solar system converted to a string" cannot be correct. First, he said "first we'll need a gigantic spool of thread". The title text obviously refers back to the title itself, about "stitching" the solar system's solid surfaces together. 108.162.221.79 13:17, 2 July 2014 (UTC)

Regarding the table, perhaps it would be better to make a separate "Surface area relative to Earth" column? Or may be just a numeric order according to size? The scientific notation of areas does not sort by ascending/descending order very well. 173.245.62.62 14:09, 2 July 2014 (UTC) Also, the average adult skin is around 1.73 square meters. For a newborn, it is 0.25.[2]. Very roughly estimating 1 sq. meter as the mean BSA, we get 7 billion sq. meters, or 7000 sq. km of human skin. That would be slightly larger than the area of either Palestine or Delaware. 173.245.62.62 (talk) (please sign your comments with ~~~~)

The first has been done - the second has been included in explain.Kynde (talk) 20:13, 3 July 2014 (UTC)

Should there not be a pixel (or perhaps a slightly grey pixel) for Asteroid 4942 Monroe - area of about 1-3×102 Km2?? Esp666 (talk) 16:34, 2 July 2014 (UTC)

It would be included in the asteroids larger than 1 km as it is about 6-10 km according to Randall. Kynde (talk) 21:00, 2 July 2014 (UTC)
Sedna and Quaoar

Why are Sedna and Quaoar not included? I mean, Sedna is so fantastically far away that I can sort of understand not including it. But Quaoar is only 10% further from the sun than Pluto or Haumea, and it's actualy closer than Makemake! 108.162.238.165 13:33, 2 July 2014 (UTC)

Probably because we do not yet know if they have a stable surface. They would thus be included in the Various or asteroids sections. Kynde (talk) 21:00, 2 July 2014 (UTC)
This has now been explained in details - as the why is due to the fact that they have yet to be proven to be rounded by their own gravitational pull... Kynde (talk) 20:13, 3 July 2014 (UTC)
Sorting

The numerical column needs to be rewritten (preferably as two columns) in order for sorting to be useful. - Frankie (talk) 14:27, 2 July 2014 (UTC)

Done Kynde (talk) 20:13, 3 July 2014 (UTC)

Well the "blank" spot around the earth continents is obviously all the other "solid" stuff we know earth is made up of, the continents are all above sea level are displayed as we see them from space - the rest of the "blank" area is solid mass under the ocean we don't see from up above but know is there through the sciences! 173.245.52.181 (talk) (please sign your comments with ~~~~)

Perhaps this is the Earth's surface after all the bodies of water vanish? http://what-if.xkcd.com/103/
Wwoods (talk) 21:07, 2 July 2014 (UTC)
The water is a so insignificant layer on top of the earths surface (crust) so as not to be included. The continents are just drawn for the scale. Kynde (talk) 20:07, 3 July 2014 (UTC)

Hannibal Lecter

I think that should be Buffalo Bill. Hannibal ate his victims, Bill sewed their skins into "clothing". --173.245.52.153 01:41, 3 July 2014 (UTC)

Corrected, thanks Kynde (talk) 20:07, 3 July 2014 (UTC)

Coastline paradox

Doesn't this thing suffer from the Coastline paradox? If that paradox applies to suface areas of 3D objects, then the surface areas of planets and other objects would be infinite or very large. Even if that is not the case, I don't think the 4*pi*r formula would work properly. Theme (talk) 09:40, 3 July 2014 (UTC)

The difficulty would lie in stretching every mountain and basin into a completely flat surface, which Randall has ignored--You'd need a space iron[3] to do that, besides the space needle. Even the map of our continents would be rather different if the folded surface of every geographic relief was accounted for. Also, that is why very small objects (including tiny asteroids and dust) have been ignored. 103.22.201.239 11:17, 3 July 2014 (UTC)
If you do as suggested in the explain - skin the planets (ie. for the earth cut of the crust above the mantle) then you would probably be able to flex this around a lot, even before mountains moved much (earth quakes fur sure, but not something that would alter the shape of the continents on the scale of this map). On a scale of the crust (which can be 70 km wide under continents) the mountains are generally not very high. If you leave the highest parts in the middle of the "skin" as in the earth area, then they would not need to be hammered out, for two surfaces to be stitched at the edges. In the end the map is maybe just shown for reference. How the continents looked afterwards is not important to Randall (as for Buffalo Bill in Silence of the Lambs and the original women). The surface area is stretched and cut up in order for them to fit each other. Kynde (talk) 20:07, 3 July 2014 (UTC)
On the scale of this map, there would be no coastline paradox. This only occurs of you wish to go into details. You just overlap the edges of each surface and sew them together. If there are a few million square meters lost here and there is is of no consequence, except for at the human skin area - but this can probably be stretched quite a bit to make it fit ;) Kynde (talk) 20:07, 3 July 2014 (UTC)
Checking the size of the areas

I have been trying to check if Randall has drawn the areas in the correct relative size (to Earth). For instance I could find that the area of The Moon fit more than 13 but less than 14 times on top of the area of Earth (as it should do 13.5 - see new column in the table with these numbers.) Similarly I have checked that there are room for just a little more than 6 Titans on Earth, and that Earth is slightly larger than the Venus area. Also Mars have been checked against earth. It do not have to be checked against earth. For instance if Titan checks out, this can be used to check other object. In this way I have use Titan to see if the area of the moons of Jupiter and Mercury fits. Ganymede, Titan, Mercury and Callisto come in that order. And the other three fit well with Titan, as do Europa. However, I find that Io is not only half the size of Titan (as it should be, but it can be rather difficult to measure.) It would be cool if someone could check on the other areas.

So far I have checked (to my satisfaction) that the following fits with the area of Earth:

  1. Venus
  2. Mars
  3. Ganymede
  4. Titan
  5. Mercury
  6. Callisto
  7. The Moon
  8. Europa

And only found that I'm uncertain with

  1. Io

Kynde (talk) 22:10, 3 July 2014 (UTC)

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