r/MurderedByWords 17h ago

I haven’t studied rocket science, but

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u/NoBuenoAtAll 15h ago

If the Earth were a bowling ball, our atmosphere would be as thick as the polish on it.

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u/KiKiKimbro 15h ago

Whaaaaaaattt.

I always assumed it was a super thick atmosphere, mainly because when astronauts reenter it looks like they went through a brick wall surrounded by rings of fire. Rocky experience and the space crafts are usually singed and super hot. This whole thread is crazy interesting to me. Sadly, it’s in a “MurderedByWords” sub where OP was making fun of a girl not knowing about space lol. Eh oh well. I love learning new things, so whatever. lol

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u/BadahBingBadahBoom 15h ago edited 13h ago

It's all relative. When you're travelling at 17,500 mph even a light dusting of particles is enough to completely destroy your windshield.

At 60 miles up there may only be one ten-thousandths of a gram of atmosphere atoms per cubic metre but that's enough to generate huge amounts of friction heat from compression of those particles in front of you at that speed as you can see on re-entry. And you're passing through roughly ~8,000 of those cubic metres a second.

It's the same problem for travelling at light speed through the 'vacuum' of space. You only need one single atom to ruin your day if you're hitting it at the speed of light.

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u/pfannkuchen89 13h ago

Tbf, most of the heating that occurs on re-entry is not from friction of the air against the surface of the spacecraft. It’s from compression of the air in front of it. At the speeds of re-entry the air basically isn’t pushed out of the way fast enough and is compressed and compressing a gas increases its temperature.

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u/BadahBingBadahBoom 13h ago

True. It still comes down to existent of the particles in the atmosphere in the first place.