All of Earth's water in a single sphere

Re:All of Earth's water in a single sphere by nwiswell on Tuesday August 13, 2024 @05:33PM (#41240094)

This didn't sound right, so I did the math.

The volume of all water is 1,386,000,000 km^3, which is then 1.386e+21 liters, or right about the same number of kilograms.

The mass of Earth is about 5.972e+24 kg. So the percent fraction by mass is 0.0232%.

A "drop" is typically estimated at 1/20th of one mL, which is then 0.05 grams. We can estimate the mass of a small-ish bowling ball at 5kg, or 5000 grams. 0.05 / 5000 * 100 = 0.001%.

So it's an order of magnitude shy, but that's still closer than I expected! It's about 1 ml of beer on a bowling ball - a small splash. Or maybe a very large drop.

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Re:All of Earth's water in a single sphere by ahazred8ta on Tuesday August 13, 2024 @07:42PM (#41241029)

The sphere of water would have a surface gravity of 0.016 g, 1.6% of Earth's gravity, 1/10th of the Moon's gravity.

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Re:All of Earth's water in a single sphere by lazide on Wednesday August 14, 2024 @08:08AM (#41245130)

Alas, the atmosphere it could hold would be insufficient to avoid it all vaporizing.

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Re:All of Earth's water in a single sphere by arrowleaf on Tuesday August 13, 2024 @06:14PM (#41240388)

You'd have to use the volume of earth, not the mass. Google tells me that lava is ~3x denser than water.

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Re:All of Earth's water in a single sphere by rachofsunshine on Tuesday August 13, 2024 @06:29PM (#41240516)

Lava is not really representative of the Earth as a whole, as it turns out. The mantle (which is the vast majority of Earth's volume) isn't a liquid, it's a squishy deformable solid. Magma that comes from the mantle is only liquid because of the removal of pressure or the addition of water; it wasn't liquid down there. And a lot of lava comes from crustal melting, not mantle material.

Earth as a whole has a density about 5.5x that of water.

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Re:All of Earth's water in a single sphere by silisili on Tuesday August 13, 2024 @05:53PM (#41240248)

Thanks. This really put it in perspective for me better than the image or other analogies!

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Re:All of Earth's water in a single sphere by nvader on Wednesday August 14, 2024 @03:13AM (#41243368)

A dash.

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Re:All of Earth's water in a single sphere by outop on Wednesday August 14, 2024 @05:31AM (#41244265)

The picture already answers this question. If the earth was a bowling ball the blue sphere would be much bigger than a single drop, maybe slightly bigger than a popping boba, the size of a small grape?

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