# If the Earth was a cube

What would it be like to be standing on an edge or the corners?

I am assuming we wouldn’t fall off, but if you creeped up on an edge and peered over would it be like looking over a cliff? What would happen when you stepped over?

What would be the effect on rivers and seas that crossed edges and corners?

Thanks.

Standing on the edge would be like standing on the peak of a steeply-pitched roof.

The water of the rivers and lakes would be centered in each face of the earthly d6.

The points would be in a vaccuum.

Assuming the Earth was solid enough to support itself in the shape of a rigid cube…

Climbing up to an edge would be like climbing an incredibly tall mountain ridge; when you reached the edge, you could stand on top of it.

If there were still oceans, these would still pull themselves into a more or less spherical shape, so each face of your cube would have a lens of water on it.

Or like standing on a mountain ridge. In the middle the ridge would run horizontally, but towards to corners, it would be running uphill.

Yes, there would be six circular oceans, and above each ocean would be a share of the atmosphere.

And so would all the edges. A large part of the surface would be dry, because it would be above the atmosphere and above the weather. (Assuming that the oceans and the atmosphere have the same volume as at present).

Interesting premise. I assume you aren’t proposing any change in the laws of gravity, just a planet with an unusual shape obtained by mysterious means.

First if all, it would be hard to keep that shape, as everything, rocks, dirt, water, cars, animals and playstations, would be attracted to the center of each square side. That would make it unlikely that a river would flow over any edge or that any water would be near it.

As you walked toward the edge, you would be pulled toward the planet’s center, so would walk more slanted with respect to the ground until at the edge, you would be leaning 45 degrees and “horizontal” would feel quite tilted.

I can see one advantage: maps could be made without distortion if done a side at a time.

It not be Bizarro.

Because of the scale of the thing, I think it would just feel like living on a large, steep mountain slope, rather than feeling like the world was tilted.

I think it’s also possible that a person who grew up on a conventional spherical planet might perceive the flat sides as concave, when standing on one of them.

If the subterranean structure would still be spherical, there’d probably be a volcanic island in the middle of each ocean.

Has anyone done the calculations to prove that there would be vacuum at the vertices? Less air, yes, but how much elevation change would there be? Gravity at the center of the faces would obviously be greater than 1g, another interesting part of it all. And here is a question: on what axis is the planet spinning? Does it go through two vertices? Or through the center of two faces?

I think the “mountains” we are talking about here would be about 15,000 miles high each.

Me thought Earth was cube? What planet you live on, thank you? Hello.

My question is, would the points, or somewhere on the cube, be in geosynchronous orbit? Even if not, that would make launching payloads into space very easy… just build a rail system and have it run off the end of the world.

The earth has a volume of about 10^21 cubic metres, so each side would have a length of about 10^7 metres – 10,000 kilometres. That means that the centre of each side of the cube would be about 5,000 kilometres from the centre of the earth, and each vertex would about 8,660 kilometres from the centre of the earth. So the greatest meaningful height you could give to them as mountains would be 3,660 kilometres, or about 2,300 miles.

ok, totally missed the math before.

Earth having a (rounding off, big time) radius of 6000 Km. The ridges at their center would be 1.4 times that distance from the center: 9000 Km (rounding). So a 3000 Km elevation (Mt Everest being about 9 Km). The tips of the 8 mountains (the vertices of the cube) would be around 14000 Km. That makes an 8000 Km high peaks.

You could kick satellites into orbit!

Being at the center of a side would be like being at the bottom of a bowl. Start walking in any direction and it starts feeling progressively steeper as you near the ridgelines. If you arrive at the edge of a ridgeline and you start walking on it, it would also start feeling steeper as you get nearer to the tips.

You would only have an atmosphere at the center of the sides (over the lenses of water). I wonder what clouds would look like. Air travel from a side to the other would not be possible. Tunnels would be wicked long to go through.

posted my correction before seeing yours. Interesting that you go by volume. I am assuming a cube that could fit Earth inside.

Maybe we cold try a cube that fits inside the Earth so we can have a working atmosphere. Still, by volume kinda makes more sense.

Would atmosphere connect all sides in your scenario?

How do you figure? The shape of the earth doesn’t determine the speed necessary to maintain orbit, no matter how high you are when you launch. You are still going to have to impart enough energy to the satellite to raise its velocity to ~17,450 mph.

That’s a heck of a kick.

Looking at total work done to get satellites up, wouldn’t getting them to the corner mean an easier launch?
Like building a Mars mission in orbit so it can have smaller engines?

You get a small boost at the corners, because they are moving faster than the flat sides, but not enough to achieve orbit. Re: the Mars mission, they key there is you are in orbit, having already expended the energy to achieve 17,450 mph.

Remember this people live constantly climbing this wicked mountains. They have a heck of a kick!

M.C. Escher’s Tetrahedral Planetoid is an interesting variation on this idea.

I can’t figure out how to do a direct link, but if you go to the official M.C. Escher Website and navigate to the link “Back in Holland, 1941 to 1954”, you can see the print. You can also see Double Planetoid from the same page, which eliminates the water, but deals more clearly with what it would be like to be on an edge or vertex.

It’s well worth visiting, when you click on the thumbnails you get a large, detailed illustration.