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Comment by tambourine_man | Hacker News Reader

Always dreamt of seeing this. Don’t know if I would stand the cold, but it must be incredible.

The issue is not cold, but whether you can get a highly competitive position at the South Pole Station. In order to see the sun set, you have to be part of the skeleton crew which maintains the station during the winter-over. There are no flights going in and out during the winter. If you see the sun set over the South Pole... you'll also be stuck seeing the sun rise as well. In the months between you'll be working in perpetual night.

It's a dry cold. You'd be fine!

There's no such thing as too cold, only incorrect clothing. If you have sufficient clothing you can be quite warm at any temperature.

I dabble in the type two fun that is mountaineering, and this is true.

A good puffy and head coverings can make even the coldest temps totally bearable.

You can get infinitely hot but only so cold. Curse you thermodynamics!

I'm not entirely sure, is this practically true? I would expect there to be an upper limit to energy we can concentrate in a given volume even when cosmic scales are involved.

I believe there is a technical physical limit but it’s insanely high (which is why “temperature in the center of the sun/nuclear blast” doesn’t really work). There’s no theoretical limit, no absolute hot to go with absolute zero.

Well, heat is caused by particles moving around, and they can only go the speed of light max, so there is a limit. It's still extremely hot though, anything physical would be blown apart by the surrounding near light speed particles in an imperceptibly short time.

Although temperature can be analogised to particles moving around I believe that at the extremes the fact that's just an analogy causes problems which would be relevant here.

What do you mean by "analogised"? That's literally what's happening, at least in a classical sense, right? Brownian noise, etc? I suppose it's not quite that on a quantum level though, it's closer to nuclear physics.

Exactly, the problem is that at extremes "classical" physics doesn't explain what we can observe.

There is probably still a limit, because you need to breath fresh air.

A human breathes at about 6 liter/minute. In terms of mass and converting to seconds, that's 0.1293 gram/second.

Heat capacity of air is 0.7 Joules per gram per kelvin. So the power needed to heat up incoming air 1 degree kelvin is 0.1293*0.7=0.09051 Watt.

Times a hundred (-60C to body temperature), that's 9 watt. Since the human body produces about 100 watt of heat in total, that's maybe still feasible. But having that percentage of your body heat being drawn out through your airways and lungs is getting dangerous.

And it gets colder on Antarctica. And exertion will speed up breathing.

Researchers on Antarctica apparently deal with by breathing through snorkels that pass through their jacket, so that the rest of the body can help to heat up the air:

https://www.newscientist.com/article/dn24731-coldest-place-o...

Perhaps it would also be possible to recover some of the heat in exhaled air, by passing it through a heat exchanger for the incoming air.

Sort of like an Arrakeen stillsuit but for heat.

I'd stress that this is at the colder locations on the continent, not the South Pole. The bigger challenge is actually the altitude. Physiological altitude can (occasionally) hit 14k ft at the Pole and those days are rough.

Temperature bottoms out around -100 F/-72 C and if you're outside, you're breathing through a gaiter/balaclava). That's sufficient to warm it up. I don't recall there ever being a situation (even that cold) when breathing was challenging due to the temperature alone.

Weird fact: you can't whistle when it gets that cold. I don't know if it's something to do with the immediate dense condensation or the temperature. It's not the pressure or the humidity, because indoors is OK.

Can you explain how physiological altitude works? I've never heard of it.

This is referring to the fact that when you go up in the atmosphere over high latitudes (e.g. poles), air pressure drops faster than over the equator. So when polar people talk about "physiological altitude" they usually mean what altitude at the equator has the same air pressure as the altitude you're at down south. It will be a few thousand feet higher. Also, barometric pressure changes with weather can increase the "equivalent altitude," which is why the above commenter is saying it can "sometimes" reach 14 thousand feet. Storm fronts are generally low pressure.

To add on to what foobarbecue said, this I believe is because the earth is spinning, so just like the Earth is not a sphere (it's an oblate spheroid), the atmosphere is also "dragged" toward the equator than the poles. Sea level pressures at the equators are higher than sea level pressure at the poles because of this.

I brought one of those balaclavas where you breathe though a metal heat exchanger the first time I went to Antarctica (living up high on Erebus). Totally unnecessary and not sure it did anything other than slightly impede my breathing.

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