Watering and draining planets – math and data | Hacker News Reader

Watering and draining planets – math and data

ahstat.github.io

60 pointsmikro2nd18 comments

I somehow expected that this article would talk about technical issues on how to deliver water to planets and how to drain them and where to put that water.

To be fair, if all ice would melt, neither Greenland nor Antarctic would have hole - crust would rebound due to ice removal. Another thing - most of the melted water would flow to equator, so there should be adjusted loss to flooding in northern regions and even more calculated to equator regions.

i don't know that much about the topic why the water go to the equator, pleas some good resource about the topic, search for this is kind a mess full of fakenews and yellow press.

Could be centrifugal force due to the earths rotation but more likely has something to do with temperature. Could be a combination of both. I'm just guessing though

Yes, it has a name for it as equatorial bulge: https://www.nationalgeographic.org/encyclopedia/equator/

It was observed in other planets first: https://en.wikipedia.org/wiki/Planetary_coordinate_system#Eq...

https://en.wikipedia.org/wiki/Post-glacial_rebound

So, it could be quite possible, that even with sea level rise, crust rebound will play bigger role around poles and there might be some new lands in the sea around north pole - as it is quite shallow ocean near Russia and Canada.

Wolfram Alpha is great for some what-if scenarios: https://www.wolframalpha.com/input/?i=halley+comet+volume+%2...

If the planets had water, their surface would look very different due to erosion.

You're right, of course, but I still found it fascinating and inspiring to get some idea of what Venus would look like with seas (and a reasonable temperature to make that possible, no doubt). For me it doesn't need to be correct in every detail. Just like reading a novel, my willing suspension of disbelief can handle this level of "fantasy"/speculation.

It's a beautiful image of Venus-in-a-next-door-cosmos anyway.

> strangely the far side [of the Moon]… is higher than the near side

Is it because of a tidal effect or something due to the nearby Earth? Would the same thing happen to water on the moon?

At +1000M almost everything is gone into water. But still something is there. I wonder at how much it will completely cover the current human habitat.

How can the far side of the moon be higher than the near side without shifting the center and making them equal?

Same way that the northern hemisphere of Mars is a lot lower than the southern hemisphere - crustal thickness.

The far side has a thicker crust than the near side, apparently due to the effect of earthshine from the molten earth on the near side early in the Moon's history.

Density does not have to be uniform.

I’m no astrophysicist but centrifugal force seems like a plausible explanation.

That was phrased really oddly. I think essentially he means, the far side has a larger topographical variance.

I wonder why California isn't covered with water when the sea level rose 1000 m

Most of it is. The higher parts of the coast ranges and the bulk of the Sierra Nevada are not covered.

Water up to Mt. Diablo is one way to pin this to a potentially familiar landmark.

Bye bye, Denmark!

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