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Is there something wrong with this image?

I found it in Wikipedia's article Ecliptic coordinate system and the image's source page is here.

What bothers me is the orientation of the Earth's surface (continents).

  • The horizontal plane with the red line around the sphere represents the plane of the ecliptic. The ecliptic is basically the plane of Earth's orbit around the Sun, in as much as that can be considered to be a plane. (caveats, details, mumble, mumble J2000.0 mumble...)

  • The inclined plane with the blue line is the Celestial Equator, which basically coincides with the Equator of the Earth (...mumble...).

If I understand correctly then, the North pole of the Earth should point in a direction that is perpendicular to the Earth's equator and celestial equator, but it looks to me like this is drawn with the north pole pointing directly up.

Am I wrong, or confused, or both?

Ecliptic coordinate system?

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    $\begingroup$ The way "I see the diagram" it looks weird, but it is probably correct. My perception is that it is about frames of reference. We are used to seeing the Earth with Earth's north at the top, not at 23.5 deg from north. This picture has the ecliptic pole at the top. As you state, Earth's equator matches the celestial equator & the Earth's pole would be at right angles to it, in the middle of the white stuff at the top of the Earth. If you imagine a line from this point, perpendicular with the celestial equator it matches 0 deg latitude & is sort of sub parallel with the west coast of Africa. $\endgroup$ – Fred Oct 10 '18 at 13:37
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    $\begingroup$ The other thing that might be confusion perception is the representation of the land masses is not accurate. Looking at the representation for Europe, Italy is not present, neither is the Balkan Peninsular or the islands of Britain & Ireland & Scandinavia just look wrong! Though Iceland is present & the Arctic ice extends to far southwards. The last time I looked there wasn't an ice sheet between Iceland & Greenland. Also, the Red Sea isn't represented. $\endgroup$ – Fred Oct 10 '18 at 13:58
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    $\begingroup$ The biggest tipoff here is that Africa is "tilted" compared to a regular Mercator map, and that the ecliptic line travels northeastish from Africa, not straight east. However, I agree the other continents are placed somewhat sloppily. $\endgroup$ – user967 Oct 10 '18 at 17:32
  • $\begingroup$ @BarryCarter ya, I've deleted my old comments; 0°N, 0°E in the Gulf of Guinea is shown well below the celestial equator, as it should be. $\endgroup$ – uhoh Oct 10 '18 at 17:34
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The way "I see the diagram" it looks weird, but it is probably correct.

My perception is that it is about frames of reference. We are used to seeing the Earth with Earth's north at the top, not at 23.5 deg from the vertical.

This picture has the ecliptic pole at the top. As you state, Earth's equator matches the celestial equator. The Earth's poles would be at right angles to it and the north pole would be in the middle of the white mass at the top of the Earth - representing the Arctic ice sheet

If you imagine a line from this point, perpendicular with the celestial equator it matches zero degrees latitude and is sort of sub parallel with the west coast of Africa.

The other thing that might be confusing our perception is the representation of the land masses is not accurate.

Looking at the representation for Europe, Italy is not present, neither is the Balkan Peninsular or the islands of Britain & Ireland. Scandinavia just looks wrong! Iceland is present and the Arctic ice extends too far southwards. The last time I looked there wasn't an ice sheet between Iceland & Greenland. Also, the Red Sea isn't represented.

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  • $\begingroup$ You've convinced me. Unless the continents move or the polar ice melts in the photo in the next 24 hours (humor) I'll click accept. Thank you for your help! $\endgroup$ – uhoh Oct 10 '18 at 17:14
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    $\begingroup$ @uhoh: Humor accepted any time. :-) $\endgroup$ – Fred Oct 10 '18 at 17:16
  • $\begingroup$ The land masses are just highly generalized, because more detail might distract from the main idea of the diagram. OK, maybe a little too generalized.... $\endgroup$ – Spencer Oct 11 '18 at 1:14
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As I see it, the Earth is well oriented, but due to (over)simplification the drawing of the geographical features may be misleading. The aspects that show that the North Pole is not upwards but tilted to the right are:

  • The Mediterranean sea extends basically in an East-West direction. The (simplified) Mediterranean here is clearly tilted and not horizontal.
  • The white mass that looks as sea ice to Fred is neither the Arctic Ocean nor the Denmark Strait, but it's actually Greenland. The green masses at its left are not Greenland but a sketchy version of Baffin Island and the northeastern part of Labrador Peninsula. Seen this way, Greenland is to the right to where it would be if Earth was upright.
  • The western coast of Europe. The Iberian Peninsula and the Scandinavian Peninsulas are clearly visible in the map, allowing to draw a line between them. That line is clearly tilted compared with how it would be in a map.
  • The equator itself can be traced from the Gulf of Guinea (barely noticeably under the red ecliptic plane) to the North coast of Brazil, and it results to be clearly tilted.

Therefore, the drawing is not wrong, but just very sketchy.

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