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Comment by andi999 | Hacker News Reader

I am wondering, are globes rare where you live? They do not suffer from any distortion. Changing maps does not help, there is a theorem that no faithful planar map of a sphere exists, the video is a bit short on this.

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> They do not suffer from any distortion.

You must be from the northern hemisphere. Globes seem to be mounted upside down usually, Antarctica belongs on top.

Is there a truly rationale basis here (other than “magnetic north” which is equally arbitrary and has rotated)? I’d argue since the vast majority of the world’s population lives in the northern hemisphere, it generally makes sense to put that at the top, all else being equal.

On the contrary, it makes the most sense to place some point of the equator on top, so that you can rotate to look at any part of the globe you want, surely?

It's a lot easier to add the rest of the solar system if it rotates around the Earth horizontally, and you need that to explain the day/night cycle, seasons and tides.

Call me weird if you must, but I would prefer a globe rotate in the same fashion as the planet does: around the poles.

That's perfectly compatible with the poles being on the sides and the equator being on a vertical plane. In fact, many globes can be tilted to this position and the main rotation still happens around the poles.

Granted, but surely that would place "all points" on the equator "on top" rather than "some point"?

You're right, I spoke imprecisely. Some point on top to begin with, any other equatorial point you want with a quick spin.

They all do, but you can have more than one dimension of rotation.

Look at https://www.amazon.com/dp/B085K2ZPWB/ .

You're still free to spin the earth backwards, though.

Interesting, so a globe on a 90 degree axial tilt rather than a 23 degree one. I'm sure I've seen such (either fixed at 90 degees or variable from 0-90 degrees), but I can't see any after a quick browser online.

no, just most people lives on top that's all.

For one, the southern hemisphere is mostly water.

But if the majority of the population lives in the northern hemisphere, shouldn't that make it heavier and thus flip the earth, placing the south pole on the top?

I think there is, actually: The Milky Way Galaxy. South is "down" towards the center, North is "up" towards the exterior. It was a revelation to realize this after growing up looking at the Milky Way in Northern Europe, that we're somewhat stationary in relation to the galaxy.

Can you explain this more? I do not understand this

The galactic center roughly aligns with the constellation Sagittarius, which is considered a southern constellation.

If you try to do milky way astrophotography in the northern hemisphere you quickly find out you are limited to the late spring / early summer, because you want to be seeing the southern sky at night. Most of the year the sun is too close to Sagittarius during daylight hours, making viewing impossible.

On what basis do you pick a definition for a globe being "upside down"?

certainly not the right-hand rule.

right hand rule for orital motion instead (or am i as usual getting this wrong)

it was mostly a joke, since the right-hand rule is itself an arbitrary convention.

I think you are right though; "up" and "down" are defined by applying the right-hand rule to the orbits of the planets around the sun, not their rotation about their own axes. this is why we consider venus to spin "backwards" as opposed to being "upside down". this does lead to an odd conundrum in the case of uranus, whose axial tilt is almost a right angle. which of uranus's poles is north?

> the right-hand rule is itself an arbitrary convention

This may not be true - if magnetic monopoles exist, choice of handedness becomes linked to choice of magnetic sign convention.

The claim there is no distortion all depends on one’s perspective. Top, bottom and, obviously, size have been chosen.

Distortion shares a root with torsion, twisting.

Scaling something evenly is not distortion, nor is placing it upside down, or otherwise changing its orientation.

There is no sense or perspective in which the orientation of a globe can be said to distort the shape of its features.

I believe the other commenter is referring to a distortion of mental perspective, not geometry, and honestly I’m buying it. It’s so strange to look at a globe upside down, even though there’s nothing unnatural about it.

I honestly thought I must have missed something big until I got to your comment... It seemed painfully incongruous in my mind to equate the demonstrably geometric ‘distortion’ artifacts directly resulting from a lower dimensional representation of a sphere ... to the mathematically unrelated notion of orienting the observational frame of reference. 2D maps literally distort and misrepresent the spatial arrangement of our planet’s surface in a metaphysical sense. Globes do not suffer from this distortion of space in their spherical approximate representation of the planet. The latter seems to be the the most salient point of the thread given whether you use an actual globe or a virtual one such a Google Earth... both of which are ubiquitously common and available ... it seems practically irrelevant (if nevertheless interesting) to consider the distortion of a 2D map as an actual “problem”. And whether or not one agrees with that, it’s wholly unrelated to whether you choose to hold your 2D map or 3D globe upside and any other orientation relative to your observational frame of reference—the former remains geometrically distorted in an egregious manner and the latter not.

Hahaha. I was wondering if I shd mention this. Of course north is up (like on any map :-)). On a more serious not this is probably really a political bias, but a lot of globes can be taken out and rotated in the frame (maybe with tooling). So one shd check before buying if the north bias can be cured.

But then you need to stand on your hands to read the labels

Sports is good, isnt it

That would be cruel. The turtles would be unable to right themselves and could possibly die.

And I wonder why inflatable ball globe are not that common? Much better than globe on axis.

For kids (and adults!) the LaapFrog interactive globe is superb.

Not sure how much they've retained, but when they were younger, my kids could pinpoint every country on the globe, and knew the capital of every country.

Edit: The model we had was much less sophisticated than that currently available (no screen or videos). It had, for example, fun speed games where it would name countries and you had to find them on the globe and tap them with the stylus, competing for who could find the most countries in a set time.

I was excited to buy one for my kids, but apparently they may not have improved since then :-( https://www.amazon.com/gp/customer-reviews/RJ4ZQ1SDMKLNU/

I'm guessing there's a term for products that get worse by virtue of being "enhanced".

They really should reintroduce the old model, just with updated political geography.

You can't generally see two countries next to each other on a globe. The globe itself is accurate, but a human looking at a globe sees an orthographic projection up to binocular perspective, which is only accurate near the center. So you can't compare India to Brazil for example.

Sure you can, you just rotate the globe back and forth. You can even measure and compare it roughly using your fingers.

Use two globes?

I've had a globe since I was a young boy. I have an illuminated one in my study now. How better to explain "Great Circle" air travel?

They are in every single classroom in the US. A lot of kids, like the parent poster, just never look at them.

Thats interesting. Here they usually are not in classrooms, but at home.

No, they really aren't. While there was a globe or two in different classrooms, most classes that needed maps of sorts had pull-down maps.

Once we reached middle and high school, most classes didn't have maps. If I were building a modern school, I might not put physical maps in any classroom equipped with modern projection tools and smart boards.

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