Why is there no West Pole and East Pole?

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In summary: North Pole. Then, as people learned about the Earth's rotation, they realized that the North and South Poles were not at the center of the Earth. They decided to call them the North Pole and the South Pole, respectively.
  • #1
Jupiter60
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Why is there no West Pole and East Pole? There's a North Pole and a South Pole, but no West Pole and no East Pole.
 
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  • #2
Jupiter60 said:
Why is there no West Pole and East Pole? There's a North Pole and a South Pole, but no West Pole and no East Pole.

What would be your guess...? :smile:
 
  • #3
I think that I remembered a discussion about this subject:

Hmm...

“There's the South Pole, said Christopher Robin, and I expect there's an East Pole and a West Pole, though people don't like talking about them.”
― A.A. Milne, Winnie-the-Pooh
 
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  • #4
There is on Uranus (groan)
 
  • #5
BWV said:
There is on Uranus (groan)
Yes Uranus, if I'm not mistaken is tilted 98 degree. That they rotates from west to east.
 
  • #6
The poles mark the overall axis of spin for a planet, and there can only be one such axis, (with a pole at both ends).
The naming of the poles is arbitrary, but by convention we use North and South.
East is the direction the planet is spinning in, There is no 'Eastmost' point where you can't go further East
West is the opposite direction.
 
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  • #7
The simple answer is because the Earth rotates on an axis that is almost vertical (can't remember what angle it is tilted at). Because of this you can reach a maximum North and maximum South, meaning if you are at the South pole, no matter where you turn you can only go North, not more South, thus making it one of the poles. On the other hand, if you head East you can keep going East (or West) for as long as you want and you'll just circle the Earth without ever reaching a point where you can't go East. Thus, East and West have no poles.
 
  • #8
Jupiter60 said:
Why is there no West Pole and East Pole? There's a North Pole and a South Pole, but no West Pole and no East Pole.
Long before anyone thought that the Earth rotated, early man noticed that the North Star remained fixed, while all others rotated around it. That direction would naturally be special. When the compass was discovered, it also pointed toward the north. Defining an East/West pole would contradict all of that.
 
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  • #9
It (the word "North") is not arbitrary, and I do not believe that it is derived from the "North Star" but rather the North Star is derived from the same older word/concept. I think I recall it came out of something having to do with the direction that the sun rises.

EDIT: I Googled it to double check and yeah, it came from some old phrase meaning more or less "to the left of the rising sun". I have no recollection of where the word "South came from". You can look that one up yourself :smile:
 
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  • #10
FactChecker said:
Long before anyone thought that the Earth rotated, early man noticed that the North Star remained fixed, while all others rotated around it. That direction would naturally be special. When the compass was discovered, it also pointed toward the north. Defining an East/West pole would contradict all of that.
But the compass does not "point" to the North Star, right. It points to magnetic compass which happens to be in the north. There is no south star. We use constellation "cross"
 
  • #11
phinds said:
It (the word "North") is not arbitrary, and I do not believe that it is derived from the "North Star" but rather the North Star is derived from the same older word/concept. I think I recall it came out of something having to do with the direction that the sun rises.

EDIT: I Googled it to double check and yeah, it came from some old phrase meaning more or less "to the left of the rising sun". I have no recollection of where the word "South came from". You can look that one up yourself :smile:
South, "sud", Sol, means Sun.
In French it's "Sud", I don't know what "South" in Latin.
 
  • #12
Yes, poles are used to denote 2 heads of an axis. Will you be accepting of this change ? South pole becomes North pole.
http://www.news.com.au/technology/science/Earth's-magnetic-poles-are-shifting-north-and-south-poles-set-to-flip/story-fnjwlcze-1226989893949
Also, these poles move around their axes too owing to our Earth core convection's changes.
 
  • #13
I think the point is not so much what word is used for the North Pole, but why did people think there was something worth naming in the North/South but not in the East/West. The derivation of the term "North Pole" is probably a question for an English language forum. Before people thought the Earth rotated, they could see that the North Star was stationary and all other stars revolved around it. They had a lot of beliefs related to stars and their motion. It would be surprising if they did not have a word for the North Pole.
 
  • #14
FactChecker said:
I think the point is not so much what word is used for the North Pole, but why did people think there was something worth naming in the North/South but not in the East/West. The derivation of the term "North Pole" is probably a question for an English language forum. Before people thought the Earth rotated, they could see that the North Star was stationary and all other stars revolved around it. They had a lot of beliefs related to stars and their motion. It would be surprising if they did not have a word for the North Pole.
And the sun as well. My point was that the word North evolved out of interest in the sun.
 
  • #15
On a body that is tidally locked to what it orbits, there would be a total of 6 Poles!

Consider the Earth's Moon. It has a North and South Pole. It also has an East and a West Pole, where you could stand and watch precisely 50% of the Earth, continually rolling towards you or away from you. In addition, there's a Pole with the Earth directly overhead, and another directly opposite. I've no idea what those poles would be called, however.
 
  • #16
There is a subsolar point, I guess "subterrestrial point" could work for one of them.
BobPixel said:
It also has an East and a West Pole, where you could stand and watch precisely 50% of the Earth, continually rolling towards you or away from you.
Libration changes the position of Earth a bit over time. For the same reason, we can observe nearly 60% of the surface of Moon from Earth.
 
  • #17
They do exist! Mathematically, any point on the surface of a sphere can be defined as the pole. Loosely speaking, people associate "North" with one such point. Then, the point most distant from it on the surface of the sphere may be referred to as the opposite pole. Call it "South" or "Anti-North", it matters little (and the definitions are symmetric). Now, connect the two poles with a great circle around the sphere, and you have divided it into two hemispheres. There is a catch, however. There is an infinite number of great circles passing through the two poles. Verify that you are yourself on one of them even as you read this. Thus, you must designate a third point in order to uniquely determine a single great circle. People often use "Greenwich" for this point, and use "eastern" and "western" to refer to the resulting hemispheres. Logically, it follows that the "east pole" and "west pole" are the two points on the sphere most distant from this great circle. The choice of "eastern" versus "western" is also arbitrary, people seem to like having the sun rise in the "east" and set in the "west", do not ask me why.
 
  • #18
NGNeer said:
They do exist! Mathematically, any point on the surface of a sphere can be defined as the pole.
In standard usage, "pole" means a point on the surface corresponding to the axis of rotation. There are only two such points on a rotating sphere, so I disagree w/ what you have said.
 
  • #19
BobPixel said:
On a body that is tidally locked to what it orbits, there would be a total of 6 Poles!

Consider the Earth's Moon. It has a North and South Pole. It also has an East and a West Pole, where you could stand and watch precisely 50% of the Earth, continually rolling towards you or away from you. In addition, there's a Pole with the Earth directly overhead, and another directly opposite. I've no idea what those poles would be called, however.

I don't think this is right. On the moon there would be a continuous ring of places such as you describe, and none of the points on that ring would be particularly special. That would make it more like an equator then a pole. The Earth Pole and Far Pole would be as you describe though.
 
  • #20
No. There are special points on the Moon, and there are 4 of them on Equator.
Earth is axially symmetric, so while the North and South poles are special, the Equator is a line which is special - no specific point of Equator is.
Moon is locked to Earth, so there are 4 special points along Moon equator - the subterranean point, the East and West poles, and the antiterran point.
 
  • #21
NGNeer said:
eople seem to like having the sun rise in the "east" and set in the "west", do not ask me why.
No matter where you would put east and west poles on Earth, for some places the sun would rise over the west pole and set over the east pole, which makes the concept pointless.

@Algr: The orbit around Earth makes those points on Moon special: you have the "forward" and "backward" points.
 
  • #22
The moon rotates once every 28 days. There is no East or West pole. Poles are named in rotating planets and in magnets. There is no similarity except that the Earth's North magnetic pole just coincidentally happened to be near the Earth's north pole. So it was also called North as well as many magnets since. The Earth is at a 23 degree angle so you can, in fact, travel further north than the North pole. However you would soon dip below true North because the spot you reached would soon be rotating in a southerly direction as the Earth rotates taking you with it.
 
  • #23
ebos said:
There is no similarity except that the Earth's North magnetic pole just coincidentally happened to be near the Earth's north pole.
The magnetic North pole is close to the South pole and vice versa. The magnetic north of a magnet needle points north - towards the North pole = magnetic South pole.
 
  • #24
mfb said:
The magnetic North pole is close to the South pole and vice versa. The magnetic north of a magnet needle points north - towards the North pole = magnetic South pole.

Of course you're right. But for centuries we have been calling it the North Pole so perhaps the magnetic poles should be renamed.
 
  • #25
In addition to the major N/S magnetic pole, aren't there additional 'minor' poles which point other ways ? AKA multipole with a dominant axis ?

IIRC, there's an uppity minor pole beneath South Atlantic, producing the deepening, drifting 'South Atlantic Anomaly'.

IIRC, a magnetic pole reversal doesn't do a 'head stand', it goes through a complex 'multipole' phase, where the winner takes all...
 
  • #26
Nik_2213 said:
In addition to the major N/S magnetic pole, aren't there additional 'minor' poles which point other ways ? AKA multipole with a dominant axis ?

IIRC, there's an uppity minor pole beneath South Atlantic, producing the deepening, drifting 'South Atlantic Anomaly'.

IIRC, a magnetic pole reversal doesn't do a 'head stand', it goes through a complex 'multipole' phase, where the winner takes all...

There is more than one electromagnet inside the Earth. These float around slowly and regularly flip so that North becomes South and vice versa. Now remember, these are Magnetic Poles and these flips happen quite often in the history of our planet. At times we can have more than one North and one South. The Sun has multitudes of N and S magnetic poles for example. But only one N and S geographical pole. (I know that shouldn't be 'geo' graphical but couldn't come up with the prefix asap - I'm old). I understand there's a "flip" coming up in the near future. Perhaps someone else more qualified could help us with the ETA.
 
  • #27
The moon processes so it can't have a "North star" like the Earth does. While a stellar North Pole might be definable, it won't be on the earth-horizon I described before, and (I think) it won't be 90 degrees from the Earth facing pole.
 
  • #28
North and south poles have a physically meaningful definition or description. There is no such thing for east and west poles. The only thing meaningful regarding east and west is they are the directions of sunrise and sunset. And yes, on a different planet with a different physical arrangement these words might not be meaningful.

"A place is a location with meaning."
 
  • #29
phinds said:
In standard usage, "pole" means a point on the surface corresponding to the axis of rotation. There are only two such points on a rotating sphere, so I disagree w/ what you have said.
I stand corrected. Allow me to clarify the difference. You can rotate the sphere about any line passing through its center. This includes any line connecting any two diametrically opposed (antipodal) points. Once you do, that line becomes the axis of rotation. Given two standard usage poles that are on the axis of rotation, the rest of my statements hold true -- there is an infinite number of great circles connecting the standard usage poles, "Greenwich" narrows the list down to one, the resulting hemispheres are called "eastern" and "western" and they each have a central point. The only statement that is no longer true is that these central points qualify for the definition of a standard usage pole. In this light, the original question was really asking why the Earth cannot spin about two axes simultaneously, and the answer to that is that the Earth is a rigid body in 3D space, and Euler's rotation theorem says there can only be one rotation axis.
 
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  • #30
NGNeer said:
I stand corrected. Allow me to clarify the difference. You can rotate the sphere about any line passing through its center. This includes any line connecting any two diametrically opposed (antipodal) points. Once you do, that line becomes the axis of rotation. Given two standard usage poles that are on the axis of rotation, the rest of my statements hold true -- there is an infinite number of great circles connecting the standard usage poles, "Greenwich" narrows the list down to one, the resulting hemispheres are called "eastern" and "western" and they each have a central point. The only statement that is no longer true is that these central points qualify for the definition of a standard usage pole. In this light, the original question was really asking why the Earth cannot spin about two axes simultaneously, and the answer to that is that the Earth is a rigid body in 3D space, and Euler's rotation theorem says there can only be one rotation axis.

Greenwich represents a line of longitude. Which longitude is the starting one was a matter of choice for different countries, since there is no natural beginning longitude,
or prime meridian. Eventually more and more counties adopted Greenwich as Britain became the leading maritime power. This was codified in the 19th century. Determining latitude at sea was easy, but longitude was a different matter,not settled until a clock that worked at sea was invented by some Englishman seeking the prize of several thousand pounds.
As a matter of interest, Mars has north and south poles, therefore an equator, but the 'prime meridian' was first chosen to be a crater named Airy in the 19th century.
NASA may have changed that. In any case, only a planet that does not rotate has no natural poles.
 

1. Why is there no West Pole and East Pole?

There is no West Pole and East Pole because the Earth's axis of rotation is tilted, causing the North and South Poles to be the only fixed points on the planet. The Earth rotates around this axis, creating the illusion of a West and East Pole, but they do not actually exist.

2. How does the Earth's tilt affect the existence of a West and East Pole?

The Earth's tilt, also known as its axial tilt or obliquity, is the reason why there is no West and East Pole. This tilt causes the Earth's axis to be inclined at an angle of approximately 23.5 degrees from its orbital plane. As a result, the North and South Poles are the only two points on the Earth's surface that are always in the same position relative to the stars.

3. Is there any scientific significance to the absence of a West and East Pole?

Yes, the absence of a West and East Pole has significant scientific implications. The Earth's tilt is responsible for the changing seasons, as well as the distribution of sunlight and heat around the globe. It also affects the Earth's climate and weather patterns, making it a crucial factor in understanding our planet's ecosystem.

4. Are there any other planets with a similar tilt and lack of West and East Poles?

Yes, there are other planets with a similar tilt and lack of West and East Poles. Uranus, for example, has an axial tilt of 98 degrees, causing its poles to be located near its equator. This results in extreme seasonal changes on the planet. Saturn also has a significant tilt of 27 degrees, but its poles are not fixed points due to its fast rotational speed.

5. Could there ever be a West and East Pole on Earth in the future?

No, there will never be a West and East Pole on Earth. The Earth's tilt is a fundamental aspect of its rotation and is not expected to change significantly in the future. While the Earth's axis does experience slight fluctuations, it will always remain tilted, making the North and South Poles the only two fixed points on our planet.

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