Temperature in Space: Is There Really None?

[Stalker23]

is there temperature in space?

if there are no particles, how can there be temperature?

and how can there be no temperature...temperature is the differnce in energy between objects? right...


thanks

 

[Astronuc]

Well temperature of matter reflects the kinetic energy (vibration or translational motion) of atoms. More generally it is related to the energy density of a material.

In space IIRC, the temperature is generally given about =<10 K, and perhaps that is more the case way out by the gas planets or toward Uranus and beyond.

There are atoms out there in space, by the density is extremely low, about one to a few atoms/cc.

http://cassfos02.ucsd.edu/public/tutorial/ISM.html

 

[Stalker23]

does the space around those atoms have heat? or is it just...empty space, where radiation goes through

 

[dicerandom]

The radiation itself has energy, and thus heat. The coldest you'll get out in the far reaches of space (read: far from any heat source such as a sun) is about 2.7K, the temperature of the cosmic microwave background radiation.