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by vkou 2873 days ago
Convection doesn't work in space, so you only lose heat to radiation.

Space is cold, but it doesn't feel cold.

1 comments

(Natural) convection doesn't work in free-fall. That includes the Vomit Comet[1], the ISS, the Apollo capsule between the Earth and the Moon, and so on.

Fans/blowers can drive covection artificially, though.

Convection (natural or artificial) doesn't work in the absence of a convecting fluid, even when not in free-fall.

Definitely not space: https://www.youtube.com/watch?v=xdJwG_9kF8s from about the 3 min 40 second mark.

(FWIW, the slinky stuff is also really cool; weight -- in the contact[1] sense but not in the mg sense -- is dissipational, and it's nice to see that demonstrated, so I'm glad your comment caught my attention.)

> space does not feel cold

If any part of you which you expose to space (if it's shielded from solar heating, etc.) is moist -- your skin, your eyes, your tongue, the insides of your nose -- you will feel that part getting cold very quickly thanks to evaporative cooling, which works very well in free-fall and in the absence of a convecting fluid.

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[1] http://math.ucr.edu/home/baez/physics/General/Weight/whatIsW...