Re:Space Elevator
by rich_sasha on Monday October 20, 2025 @01:45PM
(#45646829)
Likewise, it is crazy to me when I realised how thin our oceans are. I used to think of them as super deep (I mean, they are) but even the Mariana trench is a mere 0.2% of the Earth's radius. Average ocean depth is more like 0.05%.
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I didn’t think that sounded right but went and did the math and you’re actually round up to .2%. It’s .156%. And that’s already a mind numbingly scary place to be.
As a follow-up to this, even though water makes up 70% of the Earth's surface, it's only 0.02% of the Earth's mass.
Re:Space Elevator
by rich_sasha on Tuesday October 21, 2025 @04:47AM
(#45653775)
I might have messed it up, but as a follow up to your follow up, I think the depth of the ocean is comparable to the width of a single human hair compared to the head.
If you inflate a 18cm diameter head to the size of our planet, a 75um hair would be about 5km wide - which is about the average depth of our oceans.
It's one hair, not a whole head of hair!
Re:Space Elevator
by TheOtherHobbes on Monday October 20, 2025 @08:53PM
(#45651266)
We live at human scale within a thin slice of a planet-sized environment.
On the planetary scale, humans are tiny. We're more or less equivalent to bacteria.
Our entire civilisation is a skin rash.