Why can't humans survive in outer space?

That's a question with like 29 different answers, and all of them are right.

Because space kills humans in basically every way it's possible to kill something.

Space freezes you.

The average temperature in outer space is about 455 degrees below zero Fahrenheit,

about 270 degrees below zero Celsius.

That's cold enough to turn your body into a human sickle before you could even really feel the cold.

In fact, that's too cold for your body to recognize the feeling as cold.

At that temperature, you don't shiver. Your cells burst open.

Space is also a total vacuum. Zero pressure. This kills you in many ways, including by depressurizing your lungs,

causing them to explode. Lowering pressure also causes liquids to vaporize, or boil, at much

lower temperatures, right? There's less holding liquids as liquids when there's lower pressure,

less stopping them from floating away into gases.

There's actually a famous anecdote from the 60s illustrating this.

One man was testing spacesuits and got briefly exposed to a near total vacuum,

and he felt bubbling in his mouth in the moment before he lost consciousness.

His saliva was boiling.

Apes like us evolved to survive in the context of atmospheric pressure.

Space also radiates your body.

Many people don't realize this, but lethal levels of radiation are flying around the universe perpetually.

And Earth's atmosphere and magnetic field are doing yeoman's work to protect you from it, mostly.

Mostly, meaning Google sun-induced skin cancer, for examples of not quite totally.

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