How I can under that temperature with out any medium?

Question

My friend told me that out of Earth (Universe)is very hot near to sun and cold at far of sun. But I have Doubt ' with out any gas medium or other thing's' how can we compare the temperature.

Answer 1

There is gas in space, just much much less than there is in the atmosphere of the air.  

Comparisons can be drawn, and, of course, the nearer the sun you get, the faster the gaseous molecules are moving, and the further away you are, the slower they're moving.  This should seem common-sensical.

-John

Answer 2

You compare the RADIATION.  Heat comes in three colors...

Radiative

Convective

Conductive

Here is a start on radiation:  

http://csep10.phys.utk.edu/astr162/lect/...

And a comparison of all three:

http://galileo.phys.virginia.edu/classes...

Have fun.

-Fred