/sci/ - Science & Math

>>12329400
>Space is cold because its a vacuum.

space

>But people can already create vacuums on Earth by sucking out all the oxygen and air from a glass tube or something. Yet the temperature of the glass tube isnt negative 500 degrees.

a glass tube isn't space

>>12329406
but outer space is just an area with no oxygen and air. We can replicate the same thing in a glass tube.

>>12329400
Radiation.
You learned this in 5th grade, right?

>>12329411
You're not closely following the logic of your premise and conclusion

Space is cold, being against space doesn't necessarily make an object cold. Space is the best insulator because the object can't lose heat from conduction/convection

>>12329400
>why arnt vacuums inherently cold?

Oh boy.

https://www.youtube.com/watch?v=-hTAr2GkhpM

good luck

>>12329400
"Temperature" in the sense you're talking about is due to the aggregate kinetic energy (vibrations) of the molecules/atoms in a substance. If you remove everything from the container, it doesn't really make sense to talk about "temperature" in that sense anymore.

>>12329421
>space is cold
>space is the best insulator
>yet you can insulate the cold.

So what insulates space?

A vacuum does not have a temperature, because temperature is only defined in many-body Systems (and even then mostly in equilibrium)

In fact most particles in space are very fast (due to the absence of friction), which would give very high temperatures if you took their average kinetic energy. You don't however, because of the reasons given above.

The 3K you heard of are the temperature of the cosmic microwave background, to which you can assign a (black-body-radiation) temperature. It is more or less the only way to sensibly assign a temperature to outer space.

On earth this does not really work as most of this radiation is absorbed.

>>12329421
Is that why humans start to "boil" because heat generated from their bodies builds up? It can't transfer heat to what would be air?

>>12329492
No, boiling points drop with lower pressures, and since space is practically a vacuum, the liquid in your body will boil at much lower temperatures than 100 C.

Everyone on this board is a massive prick, bold of you to try and ask a sincere question that isnt to their ‘standard’

>>12329400
A plastic chair and a metal chair in a cold room will be the same temperature but only the metal chair will feel cold.
You think of something being 'cold' when really it is colder and conveys heat.

>>12329594
Not really.
We are just fed up with popscifags and have to do gatekeeping to keep the quality high enough.

>>12329400
space is cold because to all practical purposes it is at 3K and most people consider that pretty cold
even russians would acknowledge that

>>12329400
>12329400
>>12329406
>>12329411
>>12329413
>>12329421
>>12329425
>>12329426
>>12329429
>>12329484
>>12329492
>>12329519
>>12329594
>>12329611
>>12329626
>>12329639
This board is a joke and anybody who does serious work in science would not waste a second of their time here
niggers

>>12329421
>Space is the best insulator
Quite wrong, as you can also block radiative heat and have a better insulator than space.

>>12329678
Then leave

>>12329678
Get fucked.

t. Physics PhD student, 2nd rank shitposter

>>12329687
I am also a PhD student at the Joe Rogan University
pick up a book, retard

>>12329400
Evaporation causes coldness. Lack of atmospheric pressure means that any liquid you have inside of you will really want to turn into gas. And fun fact, the same way sweating on Earth cools your body, sweating in space will freeze your body. This is why we need full body spacesuits and not just helmets.

But in space, there is no atmosphere, meaning no convection. So your only option for losing heat without losing mass is radiation, which is pretty slow. This is why space rocks in the solar system aren't absolute zero. They balance the slow radiation speed with the Sun giving them more. For example, rocks near the close edge of the asteroid belt have a temperature of around 200K, which still is very cold, but -70C starts being close to temperatures that make sense to us.

So space isn't inherently cold (overheating is more of a problem in reality). On the Moon you have nights that are 140K (comfy -130C) and days that are 400K (nice and warm 120C)

>>12329693
Physics professor with a few scholarly books about nuclear physics published

Get fucked

>>12329687
>Physics PhD student
I think you are the one here who should try to get fucked every now and then

>>12329701
name them
retarded LARPer

>>12329706
ISBN: 9786219615808

>>12329706
>Implying he will Doxx himself
You are a Nigger

>>12329708
>isbnsearch
>Sorry, we could not find any information for this book. Please try a different book.
>abe
>No results
>We were unable to find exact matches based on your search for "9786219615808".
>amazon
>No results for in Books.
>book finder
>Sorry, we found no matching results at this time
>google
>Your search - isbn:9786219615808 - did not match any book results.
you are a nigger rapper on soundcloud, nigger

>>12329400
That pic reads like something straight out of GPT.

>>12329400
Your mistake is thinking space is real in the first place.

>>12329719
My nigga

>>12329715
Oh, thank god. I don't really want you on my site

>>12329594
classically with ideal gas, pV=NkT
where p is pressure, V a volume, T temperature N the number of particles and k a constant
this will already explain about 95% of the questions here.
If T gets low and/or N/V too high, the ideal gas law won’t hold anymore and we have to include quantum mechanical effects.
Either way, OP’s premise
>space is cold because it’s a vacuum
is already wrong. Istead, Earth is warm because of multiple effects, like having an atmosphere that partially insolates its blackbody radiation into outer space.

Some people seem to believe that space is a perfect vacuum, which is also not true. So yes, it does have a temperature.

Temperature is not only dependent of kinetic energy of particles, but also internal energy eg quantum states.

>>12329400
If you were suspended in a glass tube at vacuum, outside heat sources could still radiate heat onto you. When you're in a warm room, there are two things which keep you warm. First is the air temperature, which conducts heat onto you. The second (and very important for comfort) thing is radiation from the walls. You radiate heat onto them, and them back to you. If the walls are very cold then you radiate heat onto them, but they radiate little back to you. You cool down.

If you were instead suspended in a tube made of a material which absorbed radiation but radiated none, then every bit of heat you make would eventually end up getting stolen just from you radiating out and not getting anything back. You produce body heat from chemical energy, but if you just suspend a metal slug then it would just get colder and colder until it hit absolute zero. I think that would take infinite time actually, but getting to below 1k would take a reasonable amount of time for a gram of iron or whatever.
Space is sorta like that radiation absorbing tube. Not much is radiating onto you, and you're blasting thermal energy out. So you get colder. All the particles which are floating around are super cold because of this.

>>12329704
I have a wife who is an economics phd student :)

>>12329400
The best man-made vacuum is about a 10^12 atoms per cubic centimeter
the typical density of space is 1 atom per cubic centimeter

>>12329492
it's because of no pressure. learn about diving and why it will kill you if you go up too fast and apply that knowledge to space.
hint: your blood will start to "boil"

>>12329400
how do space suits even resist -270 degrees and are still malleable where the astronauts can flex them? at -270 degrees the material would already be so brittle that even the littlest ply would shatter it

>>12329400
space isn't hot or cold, temperatue is a property of matter, if you don't have matter you don't have a temperature period.

>>12329882
because space isn't -270 degrees retard, it doesn't have a temperature period.

>>12329400
Space isn't actually cold, or hot.
Heat is a property matter can have, to grossly simplify it heat is just how much molecules vibrate, the more it vibrates the hotter it feels to us.
So when there's no matter, there aren't any molecules that can vibrate, which means there's no source of heat.
So asking if Space is hot or cold is like asking what the number 4 tastes like, you can't really answer that because taste is not a property 4 has.
So space isn't actually cold at all.

And since you brought up vacuums, true vacuums pretty much don't exist, you always get a few particles floating about even in space (even though there are very little of them) and on Earth we aren't able to create Vacuums quite as empty as space.

>>12329882
It's a good freshman bio/physics problem to calculate the equilibrium temperature of the surface of a space suit containing a living astronaut at rest in interstellar space. Assume that the suit is a black body that radiates power at the rate generated by the astronaut. Make reasonable assumptions about the effective surface area of the suit.

>>12329890
how does something doesn't have a temperature? everything you've observed has a temperature

>>12329429
Lack of molecules to transfer heat
/thread

>>12329799
>The best man-made vacuum is about a 10^12 atoms per cubic centimeter
is this true?

>>12329678
who hurt you? most of the answers given by anons are correct

>>12329946
>>12329890
>>12329883
>>12329914

So space doesn't exist then?

>>12329882
Space cools things very slowly because there are very few particles to carry the heat away. The heat has to be lost by chance collisions and radiation, and it has a big meaty heater inside. Overheating might be more of a problem than freezing, but I have no idea.